@article {1137, title = {Considerations for the Accurate Measurement of Incident Photon to Current Efficiency in Photoelectrochemical Cells}, journal = {Frontiers in Energy Research}, volume = {9}, year = {2022}, month = {2022}, abstract = {In this paper we review some of the considerations and potential sources of error when conducting Incident Photon to Current Efficiency (IPCE) measurements, with focus on photoelectrochemical (PEC) cells for water splitting. The PEC aspect introduces challenges for accurate measurements often not encountered in dry PV cells. These can include slow charge transfer dynamics and, depending on conditions (such as a white light bias, which is important for samples with non-linear response to light intensity), possible composition changes, mostly at the surface, that a sample may gradually undergo as a result of chemical interactions with the aqueous electrolyte. These can introduce often-overlooked dependencies related to the timing of the measurement, such as a slower measurement requirement in the case of slow charge transfer dynamics, to accurately capture the steady-state response of the system. Fluctuations of the probe beam can be particularly acute when a Xe lamp with monochromator is used, and longer scanning times also allow for appreciable changes in the sample environment, especially when the sample is under realistically strong white light bias. The IPCE measurement system and procedure need to be capable of providing accurate measurements under specific conditions, according to sample and operating requirements. To illustrate these issues, complications, and solution options, we present example measurements of hematite photoanodes, leading to the use of a motorized rotating mirror stage to solve the inherent fluctuation and drift-related problems. For an example of potential pitfalls in IPCE measurements of metastable samples, we present measurements of BiVO4 photoanodes, which had changing IPCE spectral shapes under white-light bias.}, keywords = {device characterisation, EQE, IPCE, measurement technique, photoelectrochemical}, issn = {2296-598X}, doi = {10.3389/fenrg.2021.726069}, url = {https://www.frontiersin.org/article/10.3389/fenrg.2021.726069}, author = {Ellis, David S. and Piekner, Yifat and Grave, Daniel A. and Schnell, Patrick and Rothschild, Avner} } @article {1139, title = {Electrode optimization for efficient hydrogen production using an SO2-depolarized electrolysis cell}, journal = {International Journal of Hydrogen Energy}, volume = {47}, year = {2022}, pages = {14180-14185}, abstract = {The hybrid sulfur (HyS) cycle offers an alternative route to hydrogen and sulfuric acid production using the SO2-depolarized electrolysis (SDE) cell. This work reports the most efficient SDE operation to date at high sulfuric acid concentrations (\~{}60~wt\%) achieved through the optimization of operating conditions and cell components. We observed that open porosity in the porous transport media (PTM) plays a significant role in SDE performance as it enables efficient acid removal from the catalyst layer. The combination of membrane electrode assembly (MEA) components, such as Sulfonated Diels Alder Poly (phenylene) (SDAPP) membranes and electrodes prepared using SGL 29BC PTM, and operating conditions (103.4 kPagauge at 125~{\textdegree}C) yielded electrolysis potentials <700~mV at 500~mA/cm2 and acid concentrations >60~wt\%.}, keywords = {Catalysis, electrolysis, High pressure, Hybrid sulfur cycle, Hydrogen generation, Sulfur dioxide}, issn = {0360-3199}, doi = {https://doi.org/10.1016/j.ijhydene.2022.02.166}, url = {https://www.sciencedirect.com/science/article/pii/S0360319922007807}, author = {H{\'e}ctor R. Col{\'o}n-Mercado and Scott A. Mauger and Maximilian B. Gorensek and Cy H. Fujimoto and Aaron A. Lando and Prabhu Ganesan and Benjamin H. Meekins and Noah D. Meeks} } @article {1140, title = {Formation of 6H-Ba3Ce0.75Mn2.25O9 During Thermochemical Reduction of 12R-Ba4CeMn3O12: Identification of a Polytype in the Ba(Ce,Mn)O3 Family}, journal = {Inorganic Chemistry}, volume = {61}, year = {2022}, month = {4}, keywords = {analytical chemistry, inorganic, layered perovskite, organic, oxide, physical, polytype, STCH, thermochemistry}, doi = {10.1021/acs.inorgchem.2c00282}, author = {Strange, Nicholas A. and Park, James Eujin and Goyal, Anuj and Bell, Robert T. and Trindell, Jamie A. and Sugar, Joshua D. and Stone, Kevin H. and Coker, Eric N. and Lany, Stephan and Shulda, Sarah and Ginley, David S.} } @article {1141, title = {High-performance SO2-depolarized electrolysis cell using advanced polymer electrolyte membranes}, journal = {International Journal of Hydrogen Energy}, volume = {47}, year = {2022}, pages = {57-68}, abstract = {Three different proton conducting polymeric membrane materials (Nafion{\textregistered} 115, Nafion{\textregistered} 212, and sulfonated Diels-Alder polyphenylene [SDAPP]) were evaluated for use in SO2-depolarized electrolyzers for the production of hydrogen via the hybrid sulfur cycle. Their performance was measured using different water feed strategies to minimize overpotential losses while maintaining high product acid concentration. Both thin membranes (Nafion{\textregistered} 212 and SDAPP) showed performance superior to that of the thicker Nafion{\textregistered} 115. The SDAPP membrane electrode assembly (MEA) performed well at higher acid concentrations, maintaining low ohmic and kinetic overpotentials. Finally, short-term (100-h) stability tests under constant current conditions showed minimal degradation for the SDAPP and Nafion{\textregistered} 212 MEAs. SDAPP MEA performance approached the targets needed to make the hybrid sulfur cycle a competitive process for hydrogen production (product acid concentration >=65~wt\% H2SO4 at~<=~0.6-V cell potential and >=0.5 A-cm-2 current density).}, keywords = {Hybrid sulfur (HyS) process, Hydrogen production, Sulfonated diels-alder polyphenylene (SDAPP), Sulfur dioxide-depolarized electrolyzer (SDE), Sulfuric acid production}, issn = {0360-3199}, doi = {https://doi.org/10.1016/j.ijhydene.2021.10.019}, url = {https://www.sciencedirect.com/science/article/pii/S0360319921039343}, author = {H{\'e}ctor R. Col{\'o}n-Mercado and Maximilian B. Gorensek and Cy H. Fujimoto and Aaron A. Lando and Benjamin H. Meekins} } @article {1149, title = {Spatially resolved performance and degradation in a perfluorinated anion exchange membrane fuel cell}, journal = {Electrochimica Acta}, volume = {406}, year = {2022}, pages = {139812}, abstract = {Anion exchange membrane fuel cells may enable future operation with non-precious metal-based catalysts. These systems have a delicate sensitivity to operating conditions such as humidification levels and the presence of CO2 in the air oxidant stream. We present spatially resolved in-situ performance results that shed light on phenomena that are unique to anion exchange membrane fuel cells. For cell construction, a highly conductive perfluorinated anion exchange polymer was used as the membrane and the material in powder form as the ionomer. Experiments were conducted to investigate the effects of humidification, fuel/oxidant concentration, and carbonation effects on the performance and its distribution in the cell. The results indicated that (i) dry conditions at the cathode have a stronger effect than at the anode on overall cell performance, (ii) performance significantly suffered when humidification was below 90\%, (iii) fuel and oxidant dilution effects lead mass-transport losses and were stronger than flow rate effects, (iv) CO2 in the cathode feed stream creates an equilibration disparity between the inlet and outlet sections and CO2 purging is affected by flooding conditions, and (v) after >500~h of operation, performance deteriorates predominantly at the inlet.}, keywords = {2+1D fuel cell model, Anion Exchange membranes, Cathode dry-out, CO poisoning, Fuel cell durability, Mass transport limitations, Segmented fuel cell}, issn = {0013-4686}, doi = {https://doi.org/10.1016/j.electacta.2021.139812}, url = {https://www.sciencedirect.com/science/article/pii/S0013468621020958}, author = {Ashutosh G. Divekar and Michael R. Gerhardt and Christopher M. Antunes and Luigi Osmieri and Ami C. Yang-Neyerlin and Adam Z. Weber and Bryan S. Pivovar and Guido Bender and Andrew M. Herring} } @article {1156, title = {Energy Material Network Data Hubs}, journal = {International Journal of Advanced Computer Science and Applications}, volume = {12}, year = {2021}, abstract = {In early 2015 the United States Department of Energy conceived of a consortium of collaborative bodies based on shared expertise, data, and resources that could be targeted towards the more difficult problems in energy materials research. The concept of virtual laboratories had been envisioned and discussed earlier in the decade in response to the advent of the Materials Genome Initiative and similar scientific thrusts. To be effective, any virtual laboratory needed a robust method for data management, communication, security, data sharing, dissemination, and demonstration to work efficiently and effectively for groups of remote researchers. With the accessibility of new, easily deployed cloud technology and software frameworks, such individual elements could be integrated, and the required collaboration architecture is now possible. The developers have leveraged open-source software frameworks, customized them, and merged them into a platform to enable collaborative energy materials science, regardless of the geographic dispersal of the people and resources. After five years in operations, the systems are demonstratively an effective platform for enabling research within the Energy Material Networks (EMN). This paper will show the design and development of a secured scientific data sharing platform, the ability to customize the system to support diverse workflows, and examples of the enabled research and results connected with some of the Energy Material Networks.}, keywords = {cloud computing, consortium, data management, Energy materials research, network, virtual laboratories}, doi = {10.14569/IJACSA.2021.0120677}, url = {http://dx.doi.org/10.14569/IJACSA.2021.0120677}, author = {Robert R. White and Kristin Munch and Nicholas Wunder and Nalinrat Guba and Chitra Sivaraman and Kurt M. Van Allsburg and Huyen Dinh and Courtney Pailing} } @article {1117, title = {Factors Governing Oxygen Vacancy Formation in Oxide Perovskites}, journal = {Journal of the American Chemical Society}, volume = {143}, year = {2021}, pages = {13212-13227}, doi = {ttps://doi.org/10.1021/jacs.1c05570}, author = {R. B. Wexler and G. S. Gautam and E. B. Stechel and E. A. Carter} } @article {1158, title = {Influence of Supporting Electrolyte on Hydroxide Exchange Membrane Water Electrolysis Performance: Anolyte}, journal = {Journal of The Electrochemical Society}, volume = {168}, year = {2021}, month = {08/2021}, pages = {084512}, abstract = {Hydroxide-exchange-membrane water electrolysis (HEMWE) is an emerging hydrogen-production pathway that combines many advantages of incumbent alkaline water electrolysis (AWE) and proton-exchange-membrane water electrolysis (PEMWE). Advancement in HEMWE has been accelerated with the development of stable and conductive hydroxide exchange membranes (HEMs) and a more comprehensive understanding of alkaline gas-evolving kinetics. However, performance and durability without supporting electrolytes (SELs) remain inferior to PEMWE and AWE and little is known about the role and impact of the SELs. This study investigates the effects of SELs used as anolyte solutions in HEMWEs including cation-type, anion-type, SEL conductivity and pH, presence of carbonates and increased cation/OH- ratios on cell voltage and stability. We report our findings that (i) cell potential and high-frequency resistance did not correlate with anolyte SEL conductivity, (ii) cation-type influences cell voltage at low current densities (<50 mA cm-2) as predicted by half-cell measurements, (iii) increased cation/OH- ratio causes increased overpotentials, and (iv) carbonates are exchanged in the HEM but removed via self-purging at high current density. Overall, this study concludes that concentrated KOH is still the best SEL.}, keywords = {hydrogen production pathway, Hydroxide exchange membrane, incumbent alkaline, proton exchange membrane, supporting electrolytes, water electrolysis}, doi = {10.1149/1945-7111/ac1dcd}, url = {https://doi.org/10.1149/1945-7111/ac1dcd}, author = {Aleksandr Kiessling and Julie C. Fornaciari and Grace Anderson and Xiong Peng and Andreas Gerstmayr and Michael R. Gerhardt and Samuel McKinney and Alexey Serov and Yu Seung Kim and Barr Zulevi and Adam Z. Weber and Nemanja Danilovic} } @article {1159, title = {Layer-structured triple-conducting electrocatalyst for water-splitting in protonic ceramic electrolysis cells: Conductivities vs. activity}, journal = {Journal of Power Sources}, volume = {495}, year = {2021}, pages = {229764}, abstract = {Electron, proton and oxygen-triple-conducting materials are becoming the dominant steam electrode candidate to break the rate limit on the water-splitting reaction that throttles the performance of protonic ceramic electrolysis cells (PCECs). In this study, based on Pr2NiO4+δ Ruddlesden-Popper phase, we manipulate these conductivities by Pr-site Ba substitution to probe the correlation of each conductivity with the kinetics of the elementary reaction steps. It is found that the proton conductivity is vital to sustain an extended active surface area for faster adsorption of reactants and desorption of products. The effect of oxygen conductivity is surprisingly found insignificant in the water-splitting reaction. On the contrary, surface oxygen removal is discovered as the most rate-limiting process. The electronic conductivity is not a direct limiting factor. However, an electron transfer process between the current collector and the electrode junction could introduce extra resistance that is perceptible at a high operating temperature range. The best water-splitting activity is obtained on a proton conductivity/oxygen surface desorption capability well-balanced sample after Ba substitution. As a result, a water-splitting reaction resistance of 0.022 Ωcm2, a current density of 1.96 A/cm2 at 700~{\textdegree}C is achieved on Pr1.7Ba0.3NiO4+δ, one of the best performances for PCECs.}, keywords = {Hydrogen generation, Protonic ceramic electrolysis cells, Ruddlesden-popper phase, Triple-conducting electrocatalyst, Water-splitting}, issn = {0378-7753}, doi = {https://doi.org/10.1016/j.jpowsour.2021.229764}, url = {https://www.sciencedirect.com/science/article/pii/S0378775321003050}, author = {Wenyuan Li and Bo Guan and Tao Yang and Zhongqiu Li and Wangying Shi and Hanchen Tian and Liang Ma and Thomas L. Kalapos and Xingbo Liu} } @article {1174, title = {Mg $\less$sub$\greater$x$\less$/sub$\greater$ Zn$\less$sub$\greater$1-x $\less$/sub$\greater$O contact to CuGa$\less$sub$\greater$3$\less$/sub$\greater$Se$\less$sub$\greater$5$\less$/sub$\greater$ absorber for photovoltaic and photoelectrochemical devices}, journal = {Journal of Physics: Energy}, volume = {3}, year = {2021}, month = {jan}, pages = {024001}, abstract = {CuGa3Se5 is a promising candidate material with wide band gap for top cells in tandem photovoltaic and photoelectrochemical (PEC) devices. However, traditional CdS contact layers used with other chalcopyrite absorbers are not suitable for CuGa3Se5 due to the higher position of its conduction band (CB) minimum. Mg x Zn1- x O (MZO) is a transparent oxide with adjustable band gap and CB position as a function of magnesium composition, but its direct application is hindered by CuGa3Se5 surface oxidation. Here, MZO is investigated as a contact (n-type {\textquoteleft}buffer{\textquoteright} or {\textquoteleft}window{\textquoteright}) material to CuGa3Se5 absorbers pretreated in Cd2+ solution, and an onset potential close to 1 V vs reversible hydrogen electrode in 10 mM hexaammineruthenium (III) chloride electrolyte is demonstrated. The Cd2+ surface treatment changes the chemical composition and electronic structure of the CuGa3Se5 surface, as demonstrated by photoelectron spectroscopy measurements. The performance of CuGa3Se5 absorber with Cd2+ treated surface in the solid-state test structure depends on the Zn/Mg ratio in the MZO layer. The measured open circuit voltage of 925 mV is promising for tandem PEC water splitting with CuGa3Se5/MZO top cells.}, keywords = {Photocathode; PEC; Buffer layer; CuGaSe; MgZnO}, doi = {10.1088/2515-7655/abd3b3}, url = {https://doi.org/10.1088/2515-7655/abd3b3}, author = {Imran S Khan and Christopher P Muzzillo and Craig L Perkins and Andrew G Norman and James L Young and Nicolas Gaillard and Andriy Zakutayev} } @article {1152, title = {A mini-review on proton conduction of BaZrO 3 -based perovskite electrolytes}, journal = {Journal of Physics: Energy}, volume = {3}, year = {2021}, month = {07}, pages = {032019}, keywords = {ceramics, dopant, electrolyte, electrolytic cell, energy conversion, fuel cell, hydration, interaction, mobility, oxide, proton, proton conduction}, doi = {10.1088/2515-7655/ac12ab}, author = {Vera, Clarita and Ding, Hanping and Peterson, David and Gibbons, William and Zhou, Meng and Ding, Dong} } @article {1116, title = {Performance and Limits of 2.0 eV Bandgap CuInGaS2 Solar Absorber Integrated With CdS Buffer on F:SnO2 Substrate for Multijunction Photovoltaic and Photoelectrochemical Water Splitting Devices}, volume = {2}, year = {2021}, pages = {5752-5763}, doi = {https://doi.org/10.1039/D1MA00570G}, author = {N. Gaillard and W. Septina and J. Varley and T. Ogitsu and K. K. Ohtaki and H. A. Ishii and J. P. Bradley and C. Muzzillo and K. Zhu and F. Babbe and J. Cooper} } @article {1163, title = {Phase formation of manganese oxide thin films using pulsed laser deposition}, journal = {Mater. Adv.}, volume = {2}, year = {2021}, pages = {303-309}, abstract = {Manganese oxides have enabled a wide range of technologies including oxygen evolution catalysts, lithium ion batteries, and thermochemical water splitting. However, the variable oxidation state and rich polymorphism of manganese oxides make it difficult to find the processing conditions to target a particular phase of manganese oxide. Targeted synthesis requires a more complete understanding of the phase space and the impact of multiple processing variables on phase formation. Here, we demonstrate the impact of substrate temperature, total deposition pressure, partial pressure of oxygen, and target composition on the phase formation of manganese oxides grown using combinatorial pulsed laser deposition (PLD). Thin films were deposited from a MnO, Mn2O3 or MnO2 target onto amorphous glass substrates with a continuously varied temperature provided by a combinatorial heater. A combination of X-ray diffraction, Rutherford backscattering spectroscopy, and Raman and Fourier transform infrared (FTIR) spectroscopies were used to determine the phases present in the samples. The oxygen partial pressure was found to be the critical factor determining phase formation, while the total pressure, target composition, and substrate temperature have smaller and more complex effects on phase formation. Comparing the results of this work to the published temperature{\textendash}pressure phase diagrams shows that the PLD thin films vary significantly from the expected equilibrium phases of either the bulk materials or nanoparticles. These results suggest that PLD provides a route to capture phases of manganese oxides at lower temperatures or higher oxygen pressures than those required for bulk synthesis or solution processing.}, keywords = {Combinatorial, Manganese oxides, Pulsed laser deposition, STCH}, doi = {10.1039/D0MA00417K}, url = {http://dx.doi.org/10.1039/D0MA00417K}, author = {Garten, Lauren M. and Selvarasu, Praneetha and Perkins, John and Ginley, David and Zakutayev, Andriy} } @article {1164, title = {Regulation of Cathode Mass and Charge Transfer by Structural 3D Engineering for Protonic Ceramic Fuel Cell at 400 {\textdegree}C (Adv. Funct. Mater. 33/2021)}, journal = {Advanced Functional Materials}, volume = {31}, year = {2021}, pages = {2170244}, abstract = {3D Engineering In article number 2102907, Wei Wu, Meng Zhou, Dong Ding, and co-workers develop a 3D engineered cathode to enhance oxygen reduction reaction kinetics on a proton-conducting fuel cell at <600 {\textdegree}C. The results demonstrate remarkable cell performance at 400{\textendash}600 {\textdegree}C by effectively regulating the mass and charge transfer through the electrode and across the interface of electrolyte and electrode.}, keywords = {3D engineering, charge transfer, mass transfer, oxygen reduction reaction, p-SOEC, protonic ceramic fuel cells}, doi = {https://doi.org/10.1002/adfm.202170244}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202170244}, author = {Bian, Wenjuan and Wu, Wei and Gao, Yipeng and Gomez, Joshua Y. and Ding, Hanping and Tang, Wei and Zhou, Meng and Ding, Dong} } @article {1168, title = {Deconvolution of Water-Splitting on the Triple-Conducting Ruddlesden{\textendash}Popper-Phase Anode for Protonic Ceramic Electrolysis Cells}, journal = {ACS Applied Materials \& Interfaces}, volume = {12}, year = {2020}, note = {PMID: 33079527}, pages = {49574-49585}, keywords = {atomic layer, proton conductors, relaxation time distribution, ruddlesden-popper phase, steam electrolysis, triple-conducting}, doi = {10.1021/acsami.0c12987}, url = {https://doi.org/10.1021/acsami.0c12987}, author = {Tian, Hanchen and Li, Wenyuan and Ma, Liang and Yang, Tao and Guan, Bo and Shi, Wangying and Kalapos, Thomas L. and Liu, Xingbo} } @article {1125, title = {Exploring Ca{\textendash}Ce{\textendash}M{\textendash}O (M = 3d Transition Metal) Oxide Perovskites for Solar Thermochemical Applications}, journal = {Chemistry of Materials}, volume = {32}, year = {2020}, pages = {9964-9982}, keywords = {Perovskites, Theory-driven materials discovery}, doi = {https://doi.org/10.1021/acs.chemmater.0c02912}, author = {G. Sai Gautam and E. B. Stechel and E. A. Carter} } @article {1129, title = {A First-Principles-Based Sub-Lattice Formalism for Predicting Off-Stoichiometry in Materials for Solar Thermochemical Applications: The Example of Ceria}, journal = {Advanced Theory and Simulations}, volume = {3}, year = {2020}, keywords = {off-stoichiometric materials, sub-lattice models, thermodynamic modeling}, doi = {https://doi.org/10.1002/adts.202000112}, author = {G. Sai Gautam and E. B. Stechel and E. A. Carter} } @article {1087, title = {Highly efficient and durable III{\textendash}V semiconductor-catalyst photocathodes via a transparent protection layer}, journal = {Sustainable Energy Fuels}, volume = {4}, year = {2020}, pages = {1437-1442}, abstract = {

Durable performance and high efficiency in solar-driven water splitting are great challenges not yet co-achieved in photoelectrochemical (PEC) cells. Although photovoltaic cells made from III{\textendash}V semiconductors can achieve high optical{\textendash}electrical conversion efficiency, their functional integration with electrocatalysts and operational lifetime remain great challenges. Herein, an ultra-thin TiN layer was used as a diffusion barrier on a buried junction n+p-GaInP2 photocathode, to enable elevated temperatures for subsequent catalyst growth of Ni5P4 as nano-islands without damaging the GaInP2 junction. The resulting PEC half-cell showed negligible absorption loss, with saturated photocurrent density and H2 evolution equivalent to the benchmark photocathode decorated with PtRu catalysts. High corrosion-resistant Ni5P4/TiN layers showed undiminished photocathode operation over 120 h, exceeding previous benchmarks. Etching to remove electrodeposited copper, an introduced contaminant, restored full performance, demonstrating operational ruggedness. The TiN layer expands the synthesis conditions and protects against corrosion for stable operation of III{\textendash}V PEC devices, while the Ni5P4 catalyst replaces costly and scarce noble metal catalysts.

}, doi = {10.1039/C9SE01264H}, url = {http://dx.doi.org/10.1039/C9SE01264H}, author = {Shinjae Hwang and James L. Young and Rachel Mow and Anders B. Laursen and Mengjun Li and Hongbin Yang and Philip E. Batson and Martha Greenblatt and Myles A. Steiner and Daniel Friedman and Todd G. Deutsch and Eric Garfunkel and G. Charles Dismukes} } @article {1122, title = {Improved Performance and Efficiency of Lanthanum{\textendash}Strontium{\textendash}Manganese Perovskites Undergoing Isothermal Redox Cycling under Controlled pH2O/pH2}, journal = {Energy \& Fuels}, volume = {34}, year = {2020}, pages = {16918-16926}, keywords = {Experimental, Isothermal cycling, Perovskites}, doi = {https://doi.org/10.1021/acs.energyfuels.0c02872}, author = {K. Lee and D. C. McCord and R. J. Carrillo and B. Guyll and J. R. Scheffe} } @article {1178, title = {Tungsten oxide-coated copper gallium selenide sustains long-term solar hydrogen evolution}, journal = {Sustainable Energy \& Fuels}, volume = {5}, year = {2020}, month = {12}, keywords = {CuGaSe, durability, PEC, Photocathode, Pt hydrogen evolution catalyst, Tungsten oxide protective coating}, doi = {10.1039/d0se00487a}, author = {Palm, David W. and Muzzillo, Christopher P. and Ben-Naim, Micha and Khan, Imran and Gaillard, Nicolas and Jaramillo, Thomas F.} } @article {1179, title = {Understanding of A-site deficiency in layered perovskites: promotion of dual reaction kinetics for water oxidation and oxygen reduction in protonic ceramic electrochemical cells}, journal = {J. Mater. Chem. A}, volume = {8}, year = {2020}, pages = {14600-14608}, abstract = {Protonic ceramic electrochemical cells (PCECs) are promising solid-state energy conversion devices which enable the conversion of energy between electricity and hydrogen at intermediate temperatures. Rapid conversion between chemical and electrical energy via PCEC technology will assist in overcoming grand challenges in energy storage. To achieve highly efficient reversible operation between hydrogen production and electricity generation, boosting water-oxidation and oxygen reduction activities of the oxygen electrode while maintaining the durable operation is one of the early-stage technical opportunities. In this study, an A-site deficient layered perovskite (PrBa0.8Ca0.2)0.95Co2O6-δ has been developed as an oxygen electrode for a PCEC which presents superior electrochemical performances. The electrolysis current density reached as high as -0.72 A cm-2 at 1.3 V, and a peak power density of 0.540 W cm-2 was obtained at 600 {\textdegree}C in electrolysis and fuel cell mode, respectively. The PCEC with the new electrode shows good durability under practical operating conditions for 160 hours in both operating modes with no observable degradation. The reversibility between the electrolysis and fuel cell mode is also successfully demonstrated.}, keywords = {Durability; HTE; Layered perovskite; Protonic ceramic electrochemical cells}, doi = {10.1039/D0TA05137C}, url = {http://dx.doi.org/10.1039/D0TA05137C}, author = {Tang, Wei and Ding, Hanping and Bian, Wenjuan and Wu, Wei and Li, Wenyuan and Liu, Xingbo and Gomez, Joshua Y. and Regalado Vera, Clarita Y. and Zhou, Meng and Ding, Dong} } @article {1180, title = {Water-Stable 1D Hybrid Tin(II) Iodide Emits Broad Light with 36\% Photoluminescence Quantum Efficiency}, journal = {Journal of the American Chemical Society}, volume = {142}, year = {2020}, note = {PMID: 32283025}, pages = {9028-9038}, keywords = {Modeling, PEC, Perovskites}, doi = {10.1021/jacs.0c03004}, url = {https://doi.org/10.1021/jacs.0c03004}, author = {Spanopoulos, Ioannis and Hadar, Ido and Ke, Weijun and Guo, Peijun and Sidhik, Siraj and Kepenekian, Mika{\"e}l and Even, Jacky and Mohite, Aditya D. and Schaller, Richard D. and Kanatzidis, Mercouri G.} } @article {1083, title = {Creating stable interfaces between reactive materials: titanium nitride protects photoabsorber{\textendash}catalyst interface in water-splitting photocathodes}, journal = {Journal of Materials Chemistry A}, volume = {7}, year = {2019}, pages = {2400-2411}, abstract = {

Published on January 29th, 2019. The development of a solar-driven water splitting device that replaces costly precious metals, while achieving stable high performance, is a major challenge. Transition metal phosphides are active and low-cost catalysts for the hydrogen evolution reaction (HER), although, none thus far have exhibited stable performance when interfaced with semiconductors. Here, we report on a monolithic junction consisting of cubic-NiP2:TiN:Si, fabricated using both commercial and custom Si photovoltaics. Stable performance is achieved using an ultrathin film of crystalline TiN that effectively hinders atomic diffusion between interfaces during fabrication. Crystalline cubic-NiP2 deposited on TiN/n+p-Si retains 97\% of the bare Si photovoltage, comparable saturation current density to bare Si, and has a turnover frequency of 1.04 H2 per site per s at -100 mV applied potential. In acid, it requires only -150 mV additional overpotential compared to the benchmark, Pt/TiN/n+p-Si, to reach a HER photocurrent density of -10 mA cm-2. This photocathode maintains a stable H2 photocurrent ({\textpm}10\%) for at least 125 hours, the duration of testing. When the same layers are fabricated on a commercial Si solar cell, this photocathode produced double the photocurrent density (36.3 mA cm-2, under simulated 1.5 AM G illumination). Physical characterization gives detailed information on the properties responsible for the observed activity and durability of these interfaces. In general, the thin-film methodology presented here is widely applicable, demonstrates superior activity, and achieves long-term stability.

}, issn = {2050-7496}, doi = {10.1039/C8TA12186A}, url = {https://pubs.rsc.org/en/content/articlelanding/2019/ta/c8ta12186a}, author = {Shinjae Hwang and Spencer H. Porter and Anders B. Laursen and Hongbin Yang and Mengjun Li and Viacheslav Manichev and Karin U. D. Calvinho and Voshadhi Amarasinghe and Martha Greenblatt and Eric Garfunkel and G. Charles Dismukes} } @article {1084, title = {Dependence of interface energetics and kinetics on catalyst loading in a photoelectrochemical system}, journal = {Nano Research}, year = {2019}, abstract = {

Published on March 11th, 2019. Solar hydrogen production by the photoelectrochemical method promises a means to store solar energy. While it is generally understood that the process is highly sensitive to the nature of the interface between the semiconductor and the electrolyte, a detailed understanding of this interface is still missing. For instance, few prior studies have established a clear relationship between the interface energetics and the catalyst loading amount. Here we aim to study this relationship on a prototypical Si-based photoelectrochemical system. Two types of interfaces were examined, one with GaN nanowires as a protection layer and one without. It was found that when GaN was present, higher Pt loading (\> 0.1 μg/cm2) led to not only better water reduction (and, hence, hydrogen evolution) kinetics but also more favorable interface energetics for greater photovoltages. In the absence of the protection layer, by stark contrast, increased Pt loading exhibited no measurable influence on the interface energetics, and the main difference was observed only in the hydrogen evolution kinetics. The study sheds new light on the importance of interface engineering for further improvement of photoelectrochemical systems, especially concerning the role of catalysts and protection layers.

}, issn = {1998-0000}, doi = {10.1007/s12274-019-2346-3}, url = {https://doi.org/10.1007/s12274-019-2346-3}, author = {Yumin He and Srinivas Vanka and Tianyue Gao and Da He and Jeremy Espano and Yanyan Zhao and Qi Dong and Chaochao Lang and Yongjie Wang and Thomas W. Hamann and Zetian Mi and Dunwei Wang} } @article {1186, title = {High performance III-V photoelectrodes for solar water splitting via synergistically tailored structure and stoichiometry}, journal = {Nature Communications}, volume = {10}, year = {2019}, pages = {3388}, keywords = {Ammonium sulfide surface passivation, Antireflection, Density graded surface, GaInP2, III-V, PEC, Photocathode}, doi = {10.1038/s41467-019-11351-1}, author = {Lim, Haneol and Young, James L. and Geisz, John F. and Friedman, Daniel J. and Deutsch, Todd G. and Yoon, Jongseung} } @article {1081, title = {An In0.42Ga0.58N tunnel junction nanowire photocathode monolithically integrated on a nonplanar Si wafer}, journal = {Nano Energy}, volume = {57}, year = {2019}, pages = {405-413}, abstract = {

Published on March 1st, 2019. Group III-nitride semiconductors exhibit many ideal characteristics for solar water splitting, including a tunable energy bandgap across nearly the entire solar spectrum and suitable band edge positions for water oxidation and proton reduction under visible and near-infrared light irradiation. To date, however, the best reported energy conversion efficiency for III-nitride semiconductor photocathodes is still below 1\%. Here we report on the demonstration of a relatively efficient p-type In0.42Ga0.58N photocathode, which is monolithically integrated on an n-type nonplanar Si wafer through a GaN nanowire tunnel junction. The open pillar design, together with the nonplanar Si wafer can significantly maximize light trapping, whereas the tunnel junction reduces the interfacial resistance and enhances the extraction of photo-generated electrons. In addition, photodeposited Pt nanoparticles on InGaN nanowire surfaces significantly improve the cathodic performance. The nanowire photocathode exhibits a photocurrent density of 12.3 mA cm-2 at 0 V vs. RHE and an onset potential of 0.79 V vs. RHE under AM 1.5 G one-sun illumination. The maximum applied bias photon-to-current efficiency reaches 4\% at ~0.52 V vs. RHE, which is one order of magnitude higher than the previously reported values for III-nitride photocathodes. Significantly, no performance degradation was measured for over 30 h solar water splitting with a steady photocurrent density ~12 mA cm-2 without using any extra surface protection, which is attributed to the spontaneous formation of N-terminated surfaces of InGaN nanowires to protect against photocorrosion.

}, issn = {2211-2855}, doi = {10.1016/j.nanoen.2018.12.067}, url = {http://www.sciencedirect.com/science/article/pii/S2211285518309807}, author = {Yongjie Wang and Srinivas Vanka and Jiseok Gim and Yuanpeng Wu and Ronglei Fan and Yazhou Zhang and Jinwen Shi and Mingrong Shen and Robert Hovden and Zetian Mi} } @article {1065, title = {Initial approaches in benchmarking and round robin testing for proton exchange membrane water electrolyzers}, journal = {International Journal of Hydrogen Energy}, volume = {44}, year = {2019}, month = {04/2019}, pages = {9174-9187}, abstract = {

Published on April 5th, 2019. As ever-increasing amounts of renewable electricity enter the energy supply mix on a regional, national and international basis, greater emphasis is being placed on energy conversion and storage technologies to deal with the oscillations, excess and lack of electricity. Hydrogen generation via proton exchange membrane water electrolysis (PEMWE) is one technology that offers a pathway to store large amounts of electricity in the form of hydrogen. The challenges to widespread adoption of PEM water electrolyzers lie in their high capital and operating costs which both need to be reduced through R\&D. An evaluation of reported PEMWE performance data in the literature reveals that there are excessive variations of in situ performance results that make it difficult to draw conclusions on the pathway forward to performance optimization and future R\&D directions. To enable the meaningful comparison of in situ performance evaluation across laboratories there is an obvious need for standardization of materials and testing protocols. Herein, we address this need by reporting the results of a round robin test effort conducted at the laboratories of five contributors to the IEA Electrolysis Annex 30. For this effort a method and equipment framework were first developed and then verified with respect to its feasibility for measuring water electrolysis performance accurately across the various laboratories. The effort utilized identical sets of test articles, materials, and test cells, and employed a set of shared test protocols. It further defined a minimum skeleton of requirements for the test station equipment. The maximum observed deviation between laboratories at 1\ A\ cm-2 at cell temperatures of 60\ {\textdegree}C and 80\ {\textdegree}C was 27 and 20\ mV, respectively. The deviation of the results from laboratory to laboratory was 2{\textendash}3 times higher than the lowest deviation observed at one single lab and test station. However, the highest deviations observed were one-tenth of those extracted by a literature survey on similar material sets. The work endorses the urgent need to identify one or more reference sets of materials in addition to the method and equipment framework introduced here, to enable accurate comparison of results across the entire community. The results further imply that cell temperature control appears to be the most significant source of deviation between results, and that care must be taken with respect to break-in conditions and cell electrical connections for meaningful performance data.

}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2019.02.074}, url = {http://www.sciencedirect.com/science/article/pii/S0360319919306585}, author = {G. Bender and M. Carmo and T. Smolinka and A. Gago and N. Danilovic and M. Mueller and F. Ganci and A. Fallisch and P. Lettenmeier and K. A. Friedrich and K. Ayers and B. Pivovar and J. Mergel and D. Stolten} } @article {1089, title = {Molybdenum Disulfide Catalytic Coatings via Atomic Layer Deposition for Solar Hydrogen Production from Copper Gallium Diselenide Photocathodes}, journal = {ACS Applied Energy Materials}, volume = {2}, year = {2019}, pages = {1060-1066}, abstract = {

We demonstrate that applying atomic layer deposition-derived molybdenum disulfide (MoS2) catalytic coatings on copper gallium diselenide (CGSe) thin film absorbers can lead to efficient wide band gap photocathodes for photoelectrochemical hydrogen production. We have prepared a device that is free of precious metals, employing a CGSe absorber and a cadmium sulfide (CdS) buffer layer, a titanium dioxide (TiO2) interfacial layer, and a MoS2 catalytic layer. The resulting MoS2/TiO2/CdS/CGSe photocathode exhibits a photocurrent onset of +0.53 V vs RHE and a saturation photocurrent density of -10 mA cm{\textendash}2, with stable operation for \>5 h in acidic electrolyte. Spectroscopic investigations of this device architecture indicate that overlayer degradation occurs inhomogeneously, ultimately exposing the underlying CGSe absorber.

}, doi = {10.1021/acsaem.8b01562}, url = {https://doi.org/10.1021/acsaem.8b01562}, author = {Thomas R. Hellstern and David W. Palm and James Carter and Alex D. DeAngelis and Kimberly Horsley and Lothar Weinhardt and Wanli Yang and Monika Blum and Nicolas Gaillard and Clemens Heske and Thomas F. Jaramillo} } @article {1074, title = {New tolerance factor to predict the stability of perovskite oxides and halides}, journal = {Science Advances}, volume = {5}, year = {2019}, note = {

Copyright {\textcopyright} 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY).. This is an open-access article distributed under the terms of the Creative Commons Attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

}, month = {02/2019}, pages = {eaav0693}, abstract = {

Published on February 1st, 2019. Predicting the stability of the perovskite structure remains a long-standing challenge for the discovery of new functional materials for many applications including photovoltaics and electrocatalysts. We developed an accurate, physically interpretable, and one-dimensional tolerance factor, τ, that correctly predicts 92\% of compounds as perovskite or nonperovskite for an experimental dataset of 576 ABX3 materials (X = O2-, F-, Cl-, Br-, I-) using a novel data analytics approach based on SISSO (sure independence screening and sparsifying operator). τ is shown to generalize outside the training set for 1034 experimentally realized single and double perovskites (91\% accuracy) and is applied to identify 23,314 new double perovskites (A2BB'X6) ranked by their probability of being stable as perovskite. This work guides experimentalists and theorists toward which perovskites are most likely to be successfully synthesized and demonstrates an approach to descriptor identification that can be extended to arbitrary applications beyond perovskite stability predictions. Simple and interpretable data-driven descriptor accurately predicts the synthesizability of single and double perovskites.

}, issn = {2375-2548}, doi = {10.1126/sciadv.aav0693}, url = {https://advances.sciencemag.org/content/5/2/eaav0693}, author = {Christopher J. Bartel and Christopher Sutton and Bryan R. Goldsmith and Runhai Ouyang and Charles B. Musgrave and Luca M. Ghiringhelli and Matthias Scheffler} } @article {1192, title = {Stable Unassisted Solar Water Splitting on Semiconductor Photocathodes Protected by Multifunctional GaN Nanostructures}, journal = {ACS Energy Letters}, volume = {4}, year = {2019}, pages = {1541-1548}, keywords = {durability, GaAs, GaInP2, GaN nanowires, Ge, III-V, PEC, Photocathode, Unbiased water splitting}, doi = {10.1021/acsenergylett.9b00549}, url = {https://doi.org/10.1021/acsenergylett.9b00549}, author = {Wang, Yongjie and Schwartz, Jonathan and Gim, Jiseok and Hovden, Robert and Mi, Zetian} } @article {1193, title = {Synergistic Coupling of Proton Conductors BaZr0.1Ce0.7Y0.1Yb0.1O3-δ and La2Ce2O7 to Create Chemical Stable, Interface Active Electrolyte for Steam Electrolysis Cells}, journal = {ACS Applied Materials \& Interfaces}, volume = {11}, year = {2019}, pages = {18323-18330}, keywords = {BaZr0.1Ce0.7Y0.1Yb0.1O3-δ, durability, HTE, La2Ce2O7, Protonic ceramic electrolysis cell, SOEC}, doi = {10.1021/acsami.9b00303}, url = {https://doi.org/10.1021/acsami.9b00303}, author = {Li, Wenyuan and Guan, Bo and Ma, Liang and Tian, Hanchen and Liu, Xingbo} } @article {1194, title = {Transition Metal Arsenide Catalysts for the Hydrogen Evolution Reaction}, journal = {The Journal of Physical Chemistry C}, volume = {123}, year = {2019}, pages = {24007-24012}, keywords = {Arsenide catalyst, CoAs, Hydrogen evolution catalyst, MoAs, Modeling, PEC}, doi = {10.1021/acs.jpcc.9b05738}, url = {https://doi.org/10.1021/acs.jpcc.9b05738}, author = {Gauthier, Joseph A. and King, Laurie A. and Stults, Faith Tucker and Flores, Raul A. and Kibsgaard, Jakob and Regmi, Yagya N. and Chan, Karen and Jaramillo, Thomas F.} } @article {1098, title = {Wide-Bandgap Cu(In,Ga)S2 Photocathodes Integrated on Transparent Conductive F:SnO2 Substrates for Chalcopyrite-Based Water Splitting Tandem Devices}, journal = {ACS Applied Energy Materials}, volume = {2}, year = {2019}, month = {08/2019}, pages = {5515-5524}, abstract = {

Published on August 26th, 2019.

}, issn = {2574-0962, 2574-0962}, doi = {10.1021/acsaem.9b00690}, url = {http://pubs.acs.org/doi/10.1021/acsaem.9b00690}, author = {Nicolas Gaillard and Dixit Prasher and Marina Chong and Alexander Deangelis and Kimberly Horsley and Hope A. Ishii and John P. Bradley and Joel Varley and Tadashi Ogitsu} } @article {990, title = {Assessing the role of hydrogen in Fermi-level pinning in chalcopyrite and kesterite solar absorbers from first-principles calculations}, journal = {Journal of Applied Physics}, volume = {123}, year = {2018}, note = {

{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n\ \n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright}

}, pages = {161408}, abstract = {

Publshed on March 7th, 2018. Understanding the impact of impurities in solar absorbers is critical to engineering high-performance in devices, particularly over extended periods of time. Here, we use hybrid functional calculations to explore the role of hydrogen interstitial (Hi) defects in the electronic properties of a number of attractive solar absorbers within the chalcopyrite and kesterite families to identify how this common impurity may influence device performance. Our results identify that Hi can inhibit the highly p-type conditions desirable for several higher-band gap absorbers and that H incorporation could detrimentally affect the open-circuit voltage (Voc) and limit device efficiencies. Additionally, we find that Hi can drive the Fermi level away from the valence band edge enough to lead to n-type conductivity in a number of chalcopyrite and kesterite absorbers, particularly those containing Ag rather than Cu. We find that these effects can lead to interfacial Fermi-level pinning that can qualitatively explain the observed performance in high-Ga content CIGSe solar cells that exhibit saturation in the Voc with increasing band gap. Our results suggest that compositional grading rather than bulk alloying, such as by creating In-rich surfaces, may be a better strategy to favorably engineering improved thin-film photovoltaics with larger-band gap absorbers.

}, issn = {0021-8979}, doi = {10.1063/1.5006272}, url = {https://aip.scitation.org/doi/10.1063/1.5006272}, author = {J. B. Varley and V. Lordi and T. Ogitsu and A. Deangelis and K. Horsley and N. Gaillard} } @article {1072, title = {Evaluating transition metal oxides within DFT-SCAN and $\text{SCAN}+U$ frameworks for solar thermochemical applications}, journal = {Physical Review Materials}, volume = {2}, year = {2018}, month = {09/2018}, pages = {095401}, abstract = {

Published on September 13th, 2018. Using the strongly constrained and appropriately normed (SCAN) and SCAN+U approximations for describing electron exchange correlation (XC) within density functional theory, we investigate the oxidation energetics, lattice constants, and electronic structure of binary Ce, Mn, and Fe oxides, which are crucial ingredients for generating renewable fuels using two-step, oxide-based, solar thermochemical reactors. Unlike other common XC functionals, we find that SCAN does not overbind the O2 molecule, based on direct calculations of its bond energy and robust agreement between calculated formation enthalpies of main group oxides versus experiments. However, in the case of transition-metal oxides, SCAN systematically overestimates (i.e., yields too negative) oxidation enthalpies due to remaining self-interaction errors in the description of their ground-state electronic structure. Adding a Hubbard U term to the transition-metal centers, where the magnitude of U is determined from experimental oxidation enthalpies, significantly improves the qualitative agreement and marginally improves the quantitative agreement of SCAN+U-calculated electronic structure and lattice parameters, respectively, with experiments. Importantly, SCAN predicts the wrong ground-state structure for a few oxides, namely, Ce2O3, Mn2O3, and Fe3O4, while SCAN+U predicts the right polymorph for all systems considered in this paper. Hence, the SCAN+U framework, with an appropriately determined U, will be required to accurately describe ground-state properties and yield qualitatively consistent electronic properties for most transition-metal and rare-earth oxides.

}, doi = {10.1103/PhysRevMaterials.2.095401}, url = {https://link.aps.org/doi/10.1103/PhysRevMaterials.2.095401}, author = {Gopalakrishnan Sai Gautam and Emily A. Carter} } @article {1085, title = {Gallium nitride nanowire as a linker of molybdenum sulfides and silicon for photoelectrocatalytic water splitting}, journal = {Nature Communications}, volume = {9}, year = {2018}, month = {09/2018}, pages = {3856}, abstract = {

Published on September 21st, 2018. Sunlight-harvesting materials require the clean integration of light-absorbing and catalytic components to be efficient. Here, authors link silicon photoelectrodes and molybdenum sulfide catalysts with defect-free gallium nitride nanowire to improve photoelectrochemical hydrogen evolution.

}, issn = {2041-1723}, doi = {10.1038/s41467-018-06140-1}, url = {https://www.nature.com/articles/s41467-018-06140-1}, author = {Baowen Zhou and Xianghua Kong and Srinivas Vanka and Sheng Chu and Pegah Ghamari and Yichen Wang and Nick Pant and Ishiang Shih and Hong Guo and Zetian Mi} } @article {1195, title = {High performing triple-conductive Pr2NiO4+δ anode for proton-conducting steam solid oxide electrolysis cell }, journal = {Journal of Materials Chemistry A}, volume = {6}, year = {2018}, pages = {18057-18066}, abstract = {The development of proton-conducting solid oxide electrolysis cells for the intermediate-temperature range application is largely hindered by the limited choice of adequate anode materials. In this study, the popular solid oxide fuel cell cathode material Pr2NiO4+δ (PNO) is investigated as the anode for the electrolysis cell, considering its proton-conducting ability. The introduction of protons into the PNO lattice is confirmed through insertion-induced conductivity variation measurements. Good chemical compatibility is verified between PNO and BaZr0.2Ce0.6Y0.2O3-δ (BZCY) proton-conducting electrolyte. Excellent catalytic activity towards water splitting is observed for the PNO{\textendash}BZCY composite anode, 0.52 Ω cm2 for 550 {\textdegree}C, 0.057 Ω cm2 for 700 {\textdegree}C. The water-splitting process is disclosed by impedance spectroscopy measured under different conditions. Due to proton conduction in PNO, the PNO surface is activated for electrochemical reactions. The non-charge transfer processes account little to the electrode resistance. The performance of the PNO{\textendash}BZCY anode is determined by two charge transfer processes whose kinetics are governed the electrolyzing potential. This charge transfer-limiting nature is relatively benign since the electrode resistance has been found to exponentially reduce with increasing overpotential. Cathode-supported Ni{\textendash}BZCY//BZCY//PNO{\textendash}BZCY thin film electrolyte single cells are fabricated and characterized. \~{}95\% current efficiency is confirmed. At 700 {\textdegree}C, a current density of 977 mA cm-2 is achieved at a 1.3 V electrolyzing potential, e.g. 0.37 V overpotential, which is one of the best performances of proton-conducting steam electrolysis cells so far. The PNO{\textendash}BZCY anode accounts only for 16\% of the overall polarization resistance at 700 {\textdegree}C. These findings prove that the triple-conductive PNO is a promising anode material for proton-based steam electrolysis cells.}, keywords = {BaZr0.2Ce0.6Y0.2O3-δ, HTE, Pr2NiO4+δ, Protonic ceramic electrolysis cells, SOEC}, doi = {10.1039/C8TA04018D}, url = {http://dx.doi.org/10.1039/C8TA04018D}, author = {Li, Wenyuan and Guan, Bo and Ma, Liang and Hu, Shanshan and Zhang, Nan and Liu, Xingbo} } @article {798, title = {Low-Cost, Efficient, and Durable H2 Production by Photoelectrochemical Water Splitting with CuGa3Se5 Photocathodes}, journal = {ACS Applied Materials \& Interfaces}, volume = {10}, year = {2018}, note = {

{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n\ \n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright}

}, pages = {19573-19579}, abstract = {

Published on June 13th, 2018. Photoelectrochemical (PEC) water splitting is an elegant method of converting sunlight and water into H2 fuel. To be commercially advantageous, PEC devices must become cheaper, more efficient, and much more durable. This work examines low-cost polycrystalline chalcopyrite films, which are successful as photovoltaic absorbers, for application as PEC absorbers. In particular, Cu{\textendash}Ga{\textendash}Se films with wide band gaps can be employed as top cell photocathodes in tandem devices as a realistic route to high efficiencies. In this report, we demonstrate that decreasing Cu/Ga composition from 0.66 to 0.31 in Cu{\textendash}Ga{\textendash}Se films increased the band gap from 1.67 to 1.86 eV and decreased saturated photocurrent density from 18 to 8 mA/cm2 as measured by chopped-light current{\textendash}voltage (CLIV) measurements in a 0.5 M sulfuric acid electrolyte. Buffer and catalyst surface treatments were not applied to the Cu{\textendash}Ga{\textendash}Se films, and they exhibited promising stability, evidenced by unchanged CLIV after 9 months of storage in air. Finally, films with Cu/Ga = 0.36 (approximately stoichiometric CuGa3Se5) and 1.86 eV band gaps had exceptional durability and continuously split water for 17 days (\~{}12 mA/cm2 at -1 V vs RHE). This is equivalent to \~{}17\ 200 C/cm2, which is a world record for any polycrystalline PEC absorber. These results indicate that CuGa3Se5 films are prime candidates for cheaply achieving efficient and durable PEC water splitting.

}, issn = {1944-8244}, doi = {10.1021/acsami.8b01447}, url = {https://doi.org/10.1021/acsami.8b01447}, author = {Christopher P. Muzzillo and W. Ellis Klein and Zhen Li and Alexander Daniel DeAngelis and Kimberly Horsley and Kai Zhu and Nicolas Gaillard} } @article {1079, title = {A photochemical diode artificial photosynthesis system for unassisted high efficiency overall pure water splitting}, journal = {Nature Communications}, volume = {9}, year = {2018}, pages = {1707}, issn = {2041-1723}, doi = {10.1038/s41467-018-04067-1}, url = {https://www.nature.com/articles/s41467-018-04067-1}, author = {Faqrul A. Chowdhury and Michel L. Trudeau and Hong Guo and Zetian Mi} } @article {1077, title = {Solar Thermochemical Hydrogen (STCH) Processes}, journal = {The Electrochemical Society Interface}, volume = {27}, year = {2018}, pages = {53-56}, issn = {1064-8208, 1944-8783}, doi = {10.1149/2.F05181if}, url = {http://interface.ecsdl.org/lookup/doi/10.1149/2.F05181if}, author = {Maximilian B. Gorensek and Claudio Corgnale and John A. Staser and John W. Weidner} } @article {1042, title = {Solar Water Oxidation by an InGaN Nanowire Photoanode with a Bandgap of 1.7 eV}, journal = {ACS Energy Letters}, volume = {3}, year = {2018}, note = {

{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n\ \n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright}

}, pages = {307-314}, abstract = {

Published on February 9th, 2018. The performance of overall solar water splitting has been largely limited by the half-reaction of water oxidation. Here, we report a 1.7 eV bandgap InGaN nanowire photoanode for efficient solar water oxidation. It produces a low onset potential of 0.1 V versus a reversible hydrogen electrode (RHE) and a high photocurrent density of 5.2 mA/cm2 at a potential as low as 0.6 V versus RHE. The photoanode yields a half-cell solar energy conversion efficiency up to 3.6\%, a record for a single-photon photoanode to our knowledge. Furthermore, in the presence of hole scavengers, the photocurrent density of the InGaN photoanode reaches 21.2 mA/cm2 at 1.23 V versus RHE, which approaches the theoretical limit for a 1.7 eV InGaN absorber. The InGaN nanowire photoanode may serve as an ideal top cell in a photoelectrochemical tandem device when stacked with a 0.9{\textendash}1.2 eV bandgap bottom cell, which can potentially deliver solar-to-hydrogen efficiency over 25\%.

}, doi = {10.1021/acsenergylett.7b01138}, url = {https://doi.org/10.1021/acsenergylett.7b01138}, author = {Sheng Chu and Srinivas Vanka and Yichen Wang and Jiseok Gim and Yongjie Wang and Yong-Ho Ra and Robert Hovden and Hong Guo and Ishiang Shih and Zetian Mi} } @article {1092, title = {Wide Band Gap CuGa(S,Se)2 Thin Films on Transparent Conductive Fluorinated Tin Oxide Substrates as Photocathode Candidates for Tandem Water Splitting Devices}, journal = {The Journal of Physical Chemistry C}, volume = {122}, year = {2018}, month = {07/2018}, pages = {14304-14312}, abstract = {

Published on July 5th, 2018. The purpose of this work was to explore the potential of CuGa(S,Se)2 thin films as wide-EG top cell absorbers for photoelectrochemical (PEC) water splitting. A synthesis was developed on fluorinated tin oxide (FTO) photocathodes by converting copper-rich co-evaporated CuGaSe2 into CuGa(S,Se)2 via a post-deposition annealing. We found it necessary to first anneal CuGaSe2 at low-temperature in sulfur then at high-temperature in nitrogen to preserve the transparency and conductivity of the FTO. Using this two-step synthesis, we fabricated a 1.72 eV CuGa(S,Se)2 photocathode with a saturation current density and photocurrent onset potential of 10 mA/cm2 and -0.20 V versus reversible hydrogen electrode, respectively. However we found that the PEC performance and sub-EG transmittance, worsened with increasing copper content. Using flatband potential measurements and the Gerischer model, we show that divergences in PEC performance of CuGa(S,Se)2 photocathodes can be explained by differences in conduction band minimums and Fermi levels. We also explain that sub-EG transmittance is likely hampered by a defect band 100{\textendash}400 meV below EC. Additional external quantum efficiency measurements of a high-efficiency 1.1 eV Cu(In,Ga)Se2 photovoltaic driver, while shaded by the CuGa(S,Se)2 photocathode, yielded a short-circuit current density of 4.14 mA/cm2 revealing that CuGa(S,Se)2 shows promise as a top cell for PEC water splitting.

}, issn = {1932-7447}, doi = {10.1021/acs.jpcc.8b02915}, url = {https://doi.org/10.1021/acs.jpcc.8b02915}, author = {Alexander D. DeAngelis and Kimberly Horsley and Nicolas Gaillard} } @article {801, title = {Characterizing Voltage Losses in an SO2 Depolarized Electrolyzer Using Sulfonated Polybenzimidazole Membranes}, journal = {Journal of The Electrochemical Society}, volume = {164}, year = {2017}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {F1591-F1595}, abstract = {Published on January 1st, 2017. The hybrid sulfur cycle has been investigated as a means to produce CO2-free hydrogen efficiently on a large scale through the decomposition of H2SO4 to SO2, O2, and H2O, and then electrochemically oxidizing SO2 back to H2SO4 with the cogeneration of H2. The net effect is the production of hydrogen and oxygen from water. Recently, sulfonated polybenzimidazoles (s-PBI) have been investigated as a replacement for Nafion due to the ability to offer increased process efficiency through the generation of higher acid concentrations at lower potentials. Here, we measure the acid concentrations and individual potential contributions toward the overall operating voltage seen in the SO2-depolarized-electrolyzer. We then determine model parameters necessary to predict voltage losses in a cell over a wide range of operating temperatures, pressures, currents and reactant flow rates.}, issn = {0013-4651, 1945-7111}, doi = {10.1149/2.1061714jes}, url = {http://jes.ecsdl.org/content/164/14/F1591}, author = {Taylor R. Garrick and Cody H. Wilkins and Andrew T. Pingitore and Jacob Mehlhoff and Alex Gulledge and Brian C. Benicewicz and John W. Weidner} } @article {1028, title = {Critical Review{\textemdash}Identifying Critical Gaps for Polymer Electrolyte Water Electrolysis Development}, journal = {Journal of The Electrochemical Society}, volume = {164}, year = {2017}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {F387-F399}, abstract = {Published on January 1st, 2017. Although polymer electrolyte water electrolyzers (PEWEs) have been used in small-scale (kW to tens of kW range) applications for several decades, PEWE technology for hydrogen production in energy applications (power-to-gas, power-to-fuel, etc.) requires significant improvements in the technology to address the challenges associated with cost, performance and durability. Systems with power of hundreds of kW or even MWs, corresponding to hydrogen production rates of around 10 to 20 kg/h, have started to appear in the past 5 years. The thin (\~{}0.2 mm) polymer electrolyte in the PEWE with low ohmic resistance, compared to the alkaline cell with liquid electrolyte, allows operation at high current densities of 1{\textendash}3 A/cm2 and high differential pressure. This article, after an introductory overview of the operating principles of PEWE and state-of-the-art, discusses the state of understanding of key phenomena determining and limiting performance, durability, and commercial readiness, identifies important {\textquoteleft}gaps{\textquoteright} in understanding and essential development needs to bring PEWE science \& engineering forward to prosper in the energy market as one of its future backbone technologies. For this to be successful, science, engineering, and process development as well as business and market development need to go hand in hand.}, issn = {0013-4651, 1945-7111}, doi = {10.1149/2.1441704jes}, url = {http://jes.ecsdl.org/content/164/4/F387}, author = {Ugljesa Babic and Michel Suermann and Felix N. B{\"u}chi and Lorenz Gubler and Thomas J. Schmidt} } @article {1030, title = {A Decade of Solid Oxide Electrolysis Improvements at DTU Energy}, journal = {ECS Transactions}, volume = {75}, year = {2017}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {3-14}, abstract = {Published on January 11th, 2017. Solid oxide electrolysis cells (SOECs) can efficiently convert electrical energy (e.g. surplus wind power) to energy stored in fuels such as hydrogen or other synthetic fuels. Performance and durability of the SOEC has increased orders of magnitudes within the last decade. This paper presents a short review of the R\&D work on SOEC single cells conducted at DTU Energy from 2005 to 2015. The SOEC improvements have involved increasing the of the oxygen electrode performance, elimination of impurities in the feed streams, optimization of processing routes, and fuel electrode structure optimization. All together, these improvements have led to a decrease in long-term degradation rate from ~40 \%/kh to ~0.4 \%/kh for steam electrolysis at -1 A/cm2, while the initial area specific resistance has been decreased from 0.44 Wcm2 to 0.15 Wcm2 at -0.5 A/cm2 and 750 {\textdegree}C.}, issn = {1938-6737, 1938-5862}, doi = {10.1149/07542.0003ecst}, url = {http://ecst.ecsdl.org/content/75/42/3}, author = {Anne Hauch and Karen Brodersen and Ming Chen and Christopher Graves and S{\o}ren H{\o}jgaard Jensen and Peter Stanley J{\o}rgensen and Peter Vang Hendriksen and Mogens Bjerg Mogensen and Simona Ovtar and Xiufu Sun} } @article {988, title = {Self-optimizing, highly surface-active layered metal dichalcogenide catalysts for hydrogen evolution}, journal = {Nature Energy}, volume = {6}, year = {2017}, note = {

{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n\ \n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright}

}, pages = {17127}, author = {Yuanyue Liu and Jingjie Wu and Ken P Hackenberg and Y. Morris Wang and Yingchao Yang and Kunttal Keyshar and Jing Gu and Tadashi Ogitsu and Robert Vajtai and Jun Lou and Pulickel M. Ajayan and Brandon C. Wood and Boris I. Yakobson} } @article {1035, title = {Current developments in reversible solid oxide fuel cells}, journal = {Renewable and Sustainable Energy Reviews}, volume = {61}, year = {2016}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {155-174}, abstract = {Published on August 1st, 2016. Solid Oxide Fuel Cells (SOFC) and Solid Oxide Electrolyte Cells (SOEC) are often considered precluded mainly by their high cost, even when several technical issues have been continuously tackled over the past decades. Our energetic matrix is essentially based on finite fuel sources, which involve the emission of environmentally hazardous pollutants. Nevertheless, now there are several feasible and profitable benign routes for energy generation through solid oxide cells development, mainly for cells capable to produce energy and store it employing hydrogen as energy carrier. Those cells act reversibly as fuel or electrolyzer systems, which may be integrated in hybrid renewable energy plants and may be referred to as Reversible Solid Oxide Fuel Cells (RSOFC). In this article, the operation principles of SOEC and SOFC and the current state of the electrolyte, fuel and oxygen electrodes has been reviewed and discussed in detail. Each major section is divided into materials families, including manufacturing issues. Novel materials and processing techniques are currently in development and are summarized here. Moreover, key-points are suggested to overcome the known drawbacks and to improve the performance and economic feasibility in order to enhance the commercialization of RSOFC technology.}, issn = {1364-0321}, doi = {10.1016/j.rser.2016.03.005}, url = {http://www.sciencedirect.com/science/article/pii/S1364032116002409}, author = {Sergio Yesid G{\'o}mez and Dachamir Hotza} } @conference {862, title = {Design and construction of a cascading pressure reactor prototype for solar-thermochemical hydrogen production}, volume = {1734}, year = {2016}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {120001}, address = {Cape Town, South Africa}, doi = {10.1063/1.4949203}, url = {http://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.4949203}, author = {Ivan Ermanoski and Johannes Grobbel and Abhishek Singh and Justin Lapp and Stefan Brendelberger and Martin Roeb and Christian Sattler and Josh Whaley and Anthony McDaniel and Nathan P. Siegel} } @article {869, title = {Effect of Flow Rates on Operation of a Solar Thermochemical Reactor for Splitting CO2 Via the Isothermal Ceria Redox Cycle}, journal = {Journal of Solar Energy Engineering}, volume = {138}, year = {2016}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {011007}, url = {https://solarenergyengineering.asmedigitalcollection.asme.org/article.aspx?articleid=2480938}, author = {Brandon J. Hathaway and Rohini Bala Chandran and Stephen Sedler and Daniel Thomas and Adam Gladen and Thomas Chase and Jane H. Davidson} } @article {963, title = {Extreme high temperature redox kinetics in ceria: Exploration of the transition from gas-phase to material-kinetic limitations}, journal = {Phys. Chem. Chem. Phys.}, volume = {18}, year = {2016}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {21554-21561}, abstract = {*The authors use electrical conductivity relaxation to measure intrinsic redox kinetics of CeO2 under STC-relevant conditions. This approach is unique to the field and demonstrates unequivocally that transport effects can confound kinetic measurements.}, issn = {1463-9076, 1463-9084}, doi = {10.1039/C6CP01935H}, url = {http://xlink.rsc.org/?DOI=C6CP01935H}, author = {Ho-Il Ji and Timothy C. Davenport and Chirranjeevi Balaji Gopal and Sossina M. Haile} } @article {794, title = {Influence of the synthesis route on the formation of 12R/10H-polytypes and their magnetic properties within the Ba(Ce,Mn)O 3 family}, journal = {New Journal of Chemistry}, volume = {39}, year = {2015}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {829-835}, issn = {1144-0546, 1369-9261}, doi = {10.1039/C4NJ00798K}, url = {http://xlink.rsc.org/?DOI=C4NJ00798K}, author = {Mario A. Mac{\'\i}as and Olivier Mentr{\'e} and Caroline Pirovano and Pascal Roussel and Silviu Colis and Gilles H. Gauthier} } @article {852, title = {Noteworthy performance of La1-xCaxMnO3 perovskites in generating H2 and CO by the thermochemical splitting of H2O and CO2}, journal = {Phys. Chem. Chem. Phys.}, volume = {17}, year = {2015}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {122-125}, issn = {1463-9076, 1463-9084}, doi = {10.1039/C4CP04578E}, url = {http://xlink.rsc.org/?DOI=C4CP04578E}, author = {Sunita Dey and B. S. Naidu and A. Govindaraj and C. N. R. Rao} } @article {844, title = {Ceria-based electrospun fibers for renewable fuel production via two-step thermal redox cycles for carbon dioxide splitting}, journal = {Physical Chemistry Chemical Physics}, volume = {16}, year = {2014}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {14271}, issn = {1463-9076, 1463-9084}, doi = {10.1039/c4cp01974a}, url = {http://xlink.rsc.org/?DOI=c4cp01974a}, author = {William T. Gibbons and Luke J. Venstrom and Robert M. De Smith and Jane H. Davidson and Gregory S. Jackson} } @article {1018, title = {Cell failure mechanisms in PEM water electrolyzers}, journal = {International Journal of Hydrogen Energy}, volume = {37}, year = {2012}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {17478-17487}, abstract = {Published on November 1st, 2012. PEM water electrolysis offers an efficient and flexible way to produce {\textquotedblleft}green-hydrogen{\textquotedblright} from renewable (intermittent) energy sources. Most research papers published in the open literature on the subject are addressing performances issues and to date, very few information is available concerning the mechanisms of performance degradation and the associated consequences. Results reported in this communication have been used to analyze the failure mechanisms of PEM water electrolysis cells which can ultimately lead to the destruction of the electrolyzer. A two-step process involving firstly the local perforation of the solid polymer electrolyte followed secondly by the catalytic recombination of hydrogen and oxygen stored in the electrolysis compartments has been evidenced. The conditions leading to the onset of such mechanism are discussed and some preventive measures are proposed to avoid accidents.}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2012.06.017}, url = {http://www.sciencedirect.com/science/article/pii/S0360319912013638}, author = {P. Millet and A. Ranjbari and F. de Guglielmo and S. A. Grigoriev and F. Aupr{\^e}tre} } @article {1005, title = {Recommended Best Practices for the Characterization of Storage Properties of Hydrogen Storage Materials | Department of Energy}, year = {2012}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, url = {https://energy.gov/eere/fuelcells/downloads/recommended-best-practices-characterization-storage-properties-hydrogen-0}, author = {Karl J. Gross and K. Russell Carrington and Steven Barcelo} } @article {994, title = {Catalytic activity of supported metal particles for sulfuric acid decomposition reaction}, journal = {Catalysis Today}, volume = {139}, year = {2009}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {291-298}, abstract = {Published on January 30th, 2009. Production of hydrogen by splitting of water in the thermochemical sulfur-based cycles that employs the catalytic decomposition of sulfuric acid into SO2 and O2 is of considerable interest. However, all of the known catalytic systems studied to date that consist of metal particles on oxide substrates deactivate with time on stream. To develop an understanding of the factors that are responsible for catalyst activity, we investigate the fresh activity of several platinum group metals (PGM) catalysts, including Pd, Pt, Rh, Ir, and Ru supported on titania at 850{\textdegree}C and perform an extensive theoretical study (density-functional-theory-based first-principles calculations and computer simulations) of the activity of the PGM nanoparticles of different size and shape positioned on TiO2 (rutile and anatase) and Al2O3 (γ- and η-alumina) surfaces. The activity and deactivation of the catalytic systems are defined by (i) the energy barrier for the detachment of O atoms from the SOn (n=1, 2, 3) species, and (ii) the removal rate of the products of the sulfuric acid decomposition (atomic O, S, and the SOn species) from metal nanoparticles. We show that these two nanoscale features collectively result in the observed experimental behavior. The removal rate of the reaction products is always lower than the SOn decomposition rates. The relation between these two rates explains why the {\textquotedblleft}softer{\textquotedblright} PGM nanoparticles (Pd and Pt) exhibit the highest initial catalytic activity.}, issn = {0920-5861}, doi = {10.1016/j.cattod.2008.03.029}, url = {http://www.sciencedirect.com/science/article/pii/S092058610800117X}, author = {Sergey N. Rashkeev and Daniel M. Ginosar and Lucia M. Petkovic and Helen H. Farrell} } @article {883, title = {Summary Report: Direct Approaches for Recycling Carbon Dioxide into Synthetic Fuel}, number = {SAND2009-0399}, year = {2009}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, abstract = {The consumption of petroleum by the transportation sector in the United States is roughly equivalent to petroleum imports into the country, which have totaled over 12 million barrels a day every year since 2004. This reliance on foreign oil is a strategic vulnerability for the economy and national security. Further, the effect of unmitigated CO2 releases on the global climate is a growing concern both here and abroad. Independence from problematic oil producers can be achieved to a great degree through the utilization of non-conventional hydrocarbon resources such as coal, oil-shale and tarsands. However, tapping into and converting these resources into liquid fuels exacerbates green house gas (GHG) emissions as they are carbon rich, but hydrogen deficient. Revolutionary thinking about energy and fuels must be adopted. We must recognize that hydrocarbon fuels are ideal energy carriers, but not primary energy sources. The energy stored in a chemical fuel is released for utilization by oxidation. In the case of hydrogen fuel the chemical product is water; in the case of a hydrocarbon fuel, water and carbon dioxide are produced. The hydrogen economy envisions a cycle in which H2O is re-energized by splitting water into H2 and O2, by electrolysis for example. We envision a hydrocarbon analogy in which both carbon dioxide and water are re-energized through the application of a persistent energy source (e.g. solar or nuclear). This is of course essentially what the process of photosynthesis accomplishes, albeit with a relatively low sunlight-to-hydrocarbon efficiency. The goal of this project then was the creation of a direct and efficient process for the solar or nuclear driven thermochemical conversion of CO2 to CO (and O2), one of the basic building blocks of synthetic fuels. This process would potentially provide the basis for an alternate hydrocarbon economy that is carbon neutral, provides a pathway to energy independence, and is compatible with much of the existing fuel infrastructure.}, url = {http://www.osti.gov/scitech/servlets/purl/952162}, author = {James E. Miller and Lindsey R. Evans and Nathan P. Siegel and Richard B. Diver and Fred Gelbard and Andrea Ambrosini and Mark D. Allendorf} } @article {864, title = {Demonstration of a solar reactor for carbon dioxide splitting via the isothermal ceria redox cycle and practical implications}, journal = {Energy \& Fuels}, volume = {30}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {6654-6661}, issn = {0887-0624, 1520-5029}, doi = {10.1021/acs.energyfuels.6b01265}, url = {http://pubs.acs.org/doi/abs/10.1021/acs.energyfuels.6b01265}, author = {Brandon J. Hathaway and Rohini Bala Chandran and Adam C. Gladen and Thomas R. Chase and Jane H. Davidson} } @article {975, title = {Design of a pilot scale directly irradiated, high temperature, and low pressure moving particle cavity chamber for metal oxide reduction}, journal = {Solar Energy}, volume = {157}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {365-376}, issn = {0038092X}, doi = {10.1016/j.solener.2017.08.040}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0038092X17307181}, author = {Abhishek Singh and Justin Lapp and Johannes Grobbel and Stefan Brendelberger and Jan P. Reinhold and Lamark Olivera and Ivan Ermanoski and Nathan P. Siegel and Anthony McDaniel and Martin Roeb and Christian Sattler} } @article {853, title = {Design principles of perovskites for thermochemical oxygen separation}, journal = {ChemSusChem}, volume = {8}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {1966-1971}, issn = {18645631}, doi = {10.1002/cssc.201500239}, url = {http://doi.wiley.com/10.1002/cssc.201500239}, author = {Miriam Ezbiri and Kyle M. Allen and Maria E. G{\`a}lvez and Ronald Michalsky and Aldo Steinfeld} } @article {998, title = {Development and testing of a PEM SO2-depolarized electrolyzer and an operating method that prevents sulfur accumulation}, journal = {International Journal of Hydrogen Energy}, volume = {40}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {13281-13294}, abstract = {The hybrid sulfur (HyS) cycle is being developed as a technology to generate hydrogen by splitting water, using heat and electrical power from a nuclear or solar power plant. A key component is the SO2-depolarized electrolysis (SDE) cell, which reacts SO2 and water to form hydrogen and sulfuric acid. SDE could also be used in once-through operation to consume SO2 and generate hydrogen and sulfuric acid for sale. A proton exchange membrane (PEM) SDE cell based on a PEM fuel cell design was fabricated and tested. Measured cell potential as a function of anolyte pressure and flow rate, sulfuric acid concentration, and cell temperature are presented for this cell. Sulfur accumulation was observed inside the cell, which could have been a serious impediment to further development. A method to prevent sulfur formation was subsequently developed. This was made possible by a testing facility that allowed unattended operation for extended periods.}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2015.08.041}, url = {http://www.sciencedirect.com/science/article/pii/S0360319915021370}, author = {John L. Steimke and Timothy J. Steeper and H{\'e}ctor R. Col{\'o}n-Mercado and Maximilian B. Gorensek} } @article {803, title = {Development of the hybrid sulfur cycle for use with concentrated solar heat. I. Conceptual design}, journal = {International Journal of Hydrogen Energy}, volume = {42}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {20939-20954}, abstract = {A detailed conceptual design of a solar hybrid sulfur (HyS) cycle is proposed. Numerous design tradeoffs, including process operating conditions and strategies, methods of integration with solar energy sources, and solar design options were considered. A baseline design was selected, and process flowsheets were developed. Pinch analyses were performed to establish the limiting energy efficiency. Detailed material and energy balances were completed, and a full stream table prepared. Design assumptions include use of: location in the southwest US desert, falling particle concentrated solar receiver, indirect heat transfer via pressurized helium, continuous operation with thermal energy storage, liquid-fed electrolyzer with PBI membrane, and bayonet-type acid decomposer. Thermochemical cycle efficiency for the HyS process was estimated to be 35.0\%, LHV basis. The solar-to-hydrogen (STH) energy conversion ratio was 16.9\%. This exceeds the Year 2015 DOE STCH target of STH >10\%, and shows promise for meeting the Year 2020 target of 20\%.}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2017.06.241}, url = {http://www.sciencedirect.com/science/article/pii/S0360319917327027}, author = {Maximilian B. Gorensek and Claudio Corgnale and William A. Summers} } @article {1020, title = {Durable Membrane Electrode Assemblies for Proton Exchange Membrane Electrolyzer Systems Operating at High Current Densities}, journal = {Electrochimica Acta}, volume = {210}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {502-511}, abstract = {High efficiencies, wide operation range and rapid response time have motivated the recent interest in proton exchange membrane (PEM) electrolysis for hydrogen generation with surplus electricity. However, degradation at high current densities and the associated mechanism has not been thoroughly explored so far. In this work, membrane electrode assemblies (MEA) from different suppliers are aged in a commercial PEM electrolyzer (2.5Nm3H2h--1), operating up to 4Acm--2 for more than 750h. In all cases, the cell voltage (Ecell) decreases during the testing period. Interestingly, the cells with Ir-black anodes exhibit the highest performance with the lowest precious metal loading (1mgcm-2). Electrochemical impedance spectroscopy (EIS) shows a progressive decrease in the specific exchange current, while the ohmic resistance decreases when doubling the nominal current density. This effect translates into an enhancement of cell efficiency at high current densities. However, Ir concurrently leaches out and diffuses into the membrane. No decrease in membrane thickness is observed at the end of the tests. High current densities do not lead to lowering the performance of the PEM electrolyzer over time, although MEA components degrade, in particular the anode.}, issn = {0013-4686}, doi = {10.1016/j.electacta.2016.04.164}, url = {http://www.sciencedirect.com/science/article/pii/S0013468616310167}, author = {P. Lettenmeier and R. Wang and R. Abouatallah and S. Helmly and T. Morawietz and R. Hiesgen and S. Kolb and F. Burggraf and J. Kallo and A. S. Gago and K. A. Friedrich} } @article {1015, title = {Failure of PEM water electrolysis cells: Case study involving anode dissolution and membrane thinning}, journal = {International Journal of Hydrogen Energy}, volume = {39}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {20440-20446}, abstract = {Polymer electrolyte membrane (PEM) water electrolysis is an efficient and environmental friendly method that can be used for the production of molecular hydrogen of electrolytic grade using zero-carbon power sources such as renewable and nuclear. However, market applications are asking for cost reduction and performances improvement. This can be achieved by increasing operating current density and lifetime of operation. Concerning performance, safety, reliability and durability issues, the membrane-electrode assembly (MEA) is the weakest cell component. Most performance losses and most accidents occurring during PEM water electrolysis are usually due to the MEA. The purpose of this communication is to report on some specific degradation mechanisms that have been identified as a potential source of performance loss and membrane failure. An accelerated degradation test has been performed on a MEA by applying galvanostatic pulses. Platinum has been used as electrocatalyst at both anode and cathode in order to accelerate degradation rate by maintaining higher cell voltage and higher anodic potential that otherwise would have occurred if conventional Ir/IrOx catalysts had been used. Experimental evidence of degradation mechanisms have been obtained by post-mortem analysis of the MEA using microscopy and chemical analysis. Details of these degradation processes are presented and discussed.}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2014.05.043}, url = {http://www.sciencedirect.com/science/article/pii/S0360319914013913}, author = {S. A. Grigoriev and K. A. Dzhus and D. G. Bessarabov and P. Millet} } @article {995, title = {High-temperature sulfuric acid decomposition over complex metal oxide catalysts}, journal = {International Journal of Hydrogen Energy}, volume = {34}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {4065-4073}, abstract = {Activity and stability of FeTiO3, MnTiO3, NiFe2O4, CuFe2O4, NiCr2O4, 2CuO{\textperiodcentered}Cr2O3, CuO and Fe2O3 for the atmospheric decomposition of concentrated sulfuric acid in sulfur-based thermochemical water splitting cycles are presented. Catalyst activity was determined at temperatures from 725 to 900{\textdegree}C. Catalytic stability was examined at 850{\textdegree}C for up to 1 week of continuous operation. The results were compared to a 1.0wt\% Pt/TiO2 catalyst. Surface area by nitrogen physisorption, X-ray diffraction analyses, and temperature programmed desorption and oxidation were used to characterize fresh and spent catalyst samples. Over the temperature range, the catalyst activity of the complex oxides followed the general trend: 2CuO{\textperiodcentered}Cr2O3>CuFe2O4>NiCr2O4≈NiFe2O4>MnTiO3≈FeTiO3. At temperatures less than 800{\textdegree}C, the 1.0wt\% Pt/TiO2 catalyst had higher activity than the complex oxides, but at temperatures above 850{\textdegree}C, the 2CuO{\textperiodcentered}Cr2O3 and CuFe2O4 samples had the highest activity. Surface area was found to decrease for all of the metal oxides after exposure to reaction conditions. In addition, the two complex metal oxides that contained chromium were not stable in the reaction environment; both leached chromium into the acid stream and decomposed into their individual oxides. The FeTiO3 sample also produced a discoloration of the reactor due to minor leaching and converted to Fe2TiO5. Fe2O3, MnTiO3 and NiFe2O4 were relatively stable in the reaction environment. In addition, CuFe2O4 catalyst appeared relatively promising due to its high activity and lack of any leaching issues; however it deactivated in week-long stability experiments. Complex metal oxides may provide an attractive alternative to platinum-based catalyst for the decomposition of sulfuric acid; however, the materials examined in this study all displayed shortcomings including material sintering, phase changes, low activity at moderated temperatures due to sulfate formation, and decomposition to their individual oxides. More effort is needed in this area to discover metal oxide materials that are less expensive, more active and more stable than platinum catalysts.}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2008.09.064}, url = {http://www.sciencedirect.com/science/article/pii/S0360319908013062}, author = {Daniel M. Ginosar and Harry W. Rollins and Lucia M. Petkovic and Kyle C. Burch and Michael J. Rush} } @article {1036, title = {Hydrogen Production From Water Electrolysis: Current Status and Future Trends}, journal = {Proceedings of the IEEE}, volume = {100}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {410-426}, abstract = {This paper reviews water electrolysis technologies for hydrogen production and also surveys the state of the art of water electrolysis integration with renewable energies. First, attention is paid to the thermodynamic and electrochemical processes to better understand how electrolysis cells work and how they can be combined to build big electrolysis modules. The electrolysis process and the characteristics, advantages, drawbacks, and challenges of the three main existing electrolysis technologies, namely alkaline, polymer electrolyte membrane, and solid oxide electrolyte, are then discussed. Current manufacturers and the main features of commercially available electrolyzers are extensively reviewed. Finally, the possible configurations allowing the integration of water electrolysis units with renewable energy sources in both autonomous and grid-connected systems are presented and some relevant demonstration projects are commented.}, issn = {0018-9219}, doi = {10.1109/JPROC.2011.2156750}, author = {A. Ursua and L. M. Gandia and P. Sanchis} } @article {753, title = {In situ high-temperature powder diffraction studies of solid oxide electrolyte direct carbon fuel cell materials in the presence of brown coal}, journal = {Journal of Materials Science}, volume = {51}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {3928-3940}, abstract = {Direct carbon fuel cells are an attractive alternative for conventional power generation; however, there is almost no information on the stability of conventional fuel cell materials in direct carbon fuel cell environments, in particular when exposed to realistic fuels and the contaminants contained within these fuels. Similarly, there is little information on the structure and phase assemblage of solid fuels exposed to typical environments found in direct carbon fuel cells. In this paper, we use in situ high-resolution synchrotron powder diffraction on conventional high-temperature fuel cell materials and untreated brown coal to assess the stability and reactivity of these materials at various temperatures up to 850 {\textdegree}C. Materials investigated include nickel metal (Ni), gadolinium-doped ceria (GDC) and yttria-stabilised zirconia (YSZ). The phase stability, crystallite size, lattice parameters and associated linear coefficient of thermal expansion were determined. The phase stability of all fuel cell materials was found to be good with no additional phase formation noted either during heating or after prolonged periods at temperature. An increase in the crystallite size was observed for both GDC and Ni. Non-linear thermal expansion observed in these materials was related to partial reduction of cerium ions (GDC) and due to a Curie point transition (Ni). A wide range of mineral phases were observed in the coal samples and these phases were found to change significantly with temperature. Mineral phases consistent with the ash composition and existing literature on Victorian brown coal were assigned to phases observed.}, issn = {1573-4803}, doi = {10.1007/s10853-015-9712-7}, url = {https://doi.org/10.1007/s10853-015-9712-7}, author = {Adam C. Rady and C. Munnings and Sarbjit Giddey and Sukhvinder P. S. Badwal and Sankar Bhattacharya and Aniruddha Kulkarni} } @article {758, title = {Incommensurate Sinusoidal Oxygen Modulations in Layered Manganites La 1 - x Sr 1 + x MnO 4 ( x >= 0.5 )}, journal = {Physical Review Letters}, volume = {109}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, issn = {0031-9007, 1079-7114}, doi = {10.1103/PhysRevLett.109.107202}, url = {https://link.aps.org/doi/10.1103/PhysRevLett.109.107202}, author = {Joaqu{\'\i}n Garc{\'\i}a and Javier Herrero-Mart{\'\i}n and Gloria Sub{\'\i}as and Javier Blasco and J. S. Andreu and M. Concepci{\'o}n S{\'a}nchez} } @article {748, title = {Investigation of oxygen vacancies in CeO2/Pt system with synchrotron light techniques}, journal = {Journal of Physics: Conference Series}, volume = {712}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {012064}, issn = {1742-6596}, doi = {10.1088/1742-6596/712/1/012064}, url = {https://doi.org/10.1088\%2F1742-6596\%2F712\%2F1\%2F012064}, author = {L. Braglia and A. L. Bugaev and K. A. Lomachenko and A. V. Soldatov and C. Lamberti and A. A. Guda} } @article {1022, title = {Long-time anodisation of titanium in sulphuric acid}, journal = {Surface and Coatings Technology}, volume = {202}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {1379-1384}, abstract = {The long-time behaviour of CP titanium in 1~M H2SO4 has been investigated. The authors revealed electrochemical behaviour during the long-time chrono-amperometric experiments. The ex-situ observations (EIS, ellipsometry, SEM and optical microscopy) brought out information concerning morphological changes of the surface as well as the change in the oxide thickness during the anodic oxidation process. From the obtained data, the authors developed a hypothesis describing the potentiostatic anodisation of titanium at voltages (up to 15~V) in 1~M H2SO4 with respect to time of anodisation.}, issn = {0257-8972}, doi = {10.1016/j.surfcoat.2007.06.027}, url = {http://www.sciencedirect.com/science/article/pii/S0257897207006676}, author = {D. Capek and M. -P. Gigandet and M. Masmoudi and M. Wery and O. Banakh} } @article {1010, title = {Low-Cost and Durable Bipolar Plates for Proton Exchange Membrane Electrolyzers}, journal = {Scientific Reports}, volume = {7}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {44035}, abstract = {Cost reduction and high efficiency are the mayor challenges for sustainable H2 production via proton exchange membrane (PEM) electrolysis. Titanium-based components such as bipolar plates (BPP) have the largest contribution to the capital cost. This work proposes the use of stainless steel BPPs coated with Nb and Ti by magnetron sputtering physical vapor deposition (PVD) and vacuum plasma spraying (VPS), respectively. The physical properties of the coatings are thoroughly characterized by scanning electron, atomic force microscopies (SEM, AFM); and X-ray diffraction, photoelectron spectroscopies (XRD, XPS). The Ti coating (50 μm) protects the stainless steel substrate against corrosion, while a 50-fold thinner layer of Nb decreases the contact resistance by almost one order of magnitude. The Nb/Ti-coated stainless steel bipolar BPPs endure the harsh environment of the anode for more than 1000 h of operation under nominal conditions, showing a potential use in PEM electrolyzers for large-scale H2 production from renewables.}, issn = {2045-2322}, doi = {10.1038/srep44035}, url = {https://www.nature.com/articles/srep44035}, author = {P. Lettenmeier and R. Wang and R. Abouatallah and B. Saruhan and O. Freitag and P. Gazdzicki and T. Morawietz and R. Hiesgen and A. S. Gago and K. A. Friedrich} } @article {925, title = {Modification of CeO2 on the redox property of Fe2O3}, journal = {Materials Letters}, volume = {93}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {129-132}, issn = {0167577X}, doi = {10.1016/j.matlet.2012.09.039}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0167577X12013195}, author = {Kongzhai Li and Masaaki Haneda and Zhenhua Gu and Hua Wang and Masakuni Ozawa} } @article {772, title = {Observation of orbital ordering and Jahn-Teller distortions supporting the Wigner-crystal model in highly doped Bi 1 - x Ca x Mn O 3}, journal = {Physical Review B}, volume = {75}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, issn = {1098-0121, 1550-235X}, doi = {10.1103/PhysRevB.75.085101}, url = {https://link.aps.org/doi/10.1103/PhysRevB.75.085101}, author = {S. Grenier and V. Kiryukhin and S-W. Cheong and B. G. Kim and J. P. Hill and K. J. Thomas and J. M. Tonnerre and Y. Joly and U. Staub and V. Scagnoli} } @article {863, title = {Origin and Tunability of Unusually Large Surface Capacitance in Doped Cerium Oxide Studied by Ambient-Pressure X-Ray Photoelectron Spectroscopy}, journal = {Advanced Materials}, volume = {28}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {4692-4697}, issn = {09359648}, doi = {10.1002/adma.201506333}, url = {http://doi.wiley.com/10.1002/adma.201506333}, author = {Chirranjeevi Balaji Gopal and Farid El Gabaly and Anthony H. McDaniel and William C. Chueh} } @article {790, title = {Photochemical Water Oxidation by Crystalline Polymorphs of Manganese Oxides: Structural Requirements for Catalysis}, journal = {Journal of the American Chemical Society}, volume = {135}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {3494-3501}, issn = {0002-7863, 1520-5126}, doi = {10.1021/ja310286h}, url = {http://pubs.acs.org/doi/10.1021/ja310286h}, author = {David M. Robinson and Yong Bok Go and Michelle Mui and Graeme Gardner and Zhijuan Zhang and Daniel Mastrogiovanni and Eric Garfunkel and Jing Li and Martha Greenblatt and G. Charles Dismukes} } @article {993, title = {Pt/TiO2 (rutile) catalysts for sulfuric acid decomposition in sulfur-based thermochemical water-splitting cycles}, journal = {Applied Catalysis A: General}, volume = {338}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {27-36}, abstract = {Thermochemical cycles consist of a series of chemical reactions to produce hydrogen from water at lower temperatures than by direct thermal decomposition. All the sulfur-based cycles for water splitting employ the sulfuric acid decomposition reaction. This work reports the studies performed on 1wt\% Pt/TiO2 (rutile) catalysts submitted to flowing concentrated sulfuric acid at 1123K and atmospheric pressure for different times on stream between 0 and 548h. Catalyst activity showed an initial decrease that lasted for about 66h, followed by a slight recovery of activity between 66 and 102h TOS, and a period of slower deactivation after 102h TOS. Catalyst sulfation did not seem to be detrimental to catalyst activity. The activity profile suggested that a complex dynamic situation, involving platinum sintering, volatilization, and oxidation, along with TiO2 morphological changes, affected catalyst activity in a non-monotonic way.}, issn = {0926-860X}, doi = {10.1016/j.apcata.2007.12.016}, url = {http://www.sciencedirect.com/science/article/pii/S0926860X07007363}, author = {L. M. Petkovic and D. M. Ginosar and H. W. Rollins and K. C. Burch and P. J. Pinhero and H. H. Farrell} } @article {771, title = {Resonant soft x-ray powder diffraction study to determine the orbital ordering in A-site-ordered SmBaMn 2 O 6}, journal = {Physical Review B}, volume = {77}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, issn = {1098-0121, 1550-235X}, doi = {10.1103/PhysRevB.77.060402}, url = {https://link.aps.org/doi/10.1103/PhysRevB.77.060402}, author = {M. Garc{\'\i}a-Fern{\'a}ndez and U. Staub and Y. Bodenthin and S. M. Lawrence and A. M. Mulders and C. E. Buckley and S. Weyeneth and E. Pomjakushina and K. Conder} } @article {764, title = {Resonant x-ray diffraction study of the charge ordering in magnetite}, journal = {Journal of Physics: Condensed Matter}, volume = {17}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {7633-7642}, issn = {0953-8984, 1361-648X}, doi = {10.1088/0953-8984/17/48/015}, url = {http://stacks.iop.org/0953-8984/17/i=48/a=015?key=crossref.b73fefddce8ebe019873c56a6156c521}, author = {Richard J Goff and Jon P Wright and J Paul Attfield and Paolo G Radaelli} } @article {761, title = {Resonant X-ray scattering as a probe of the valence and magnetic ground state and excitations in Pr0.6Ca0.4MnO3}, journal = {Physica B: Condensed Matter}, volume = {345}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {6-10}, issn = {09214526}, doi = {10.1016/j.physb.2003.11.008}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0921452603010020}, author = {S. Grenier and K.J. Thomas and Young-June Kim and J.P. Hill and Doon Gibbs and V. Kiryukhin and Y. Tokura and Y. Tomioka and D. Casa and T. Gog and C. Venkataraman} } @article {909, title = {Solar Thermochemical CO2 Splitting Utilizing a Reticulated Porous Ceria Redox System}, journal = {Energy \& Fuels}, volume = {26}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {7051-7059}, issn = {0887-0624}, doi = {10.1021/ef3013757}, url = {http://dx.doi.org/10.1021/ef3013757}, author = {Philipp Furler and Jonathan Scheffe and Michal Gorbar and Louis Moes and Ulrich Vogt and Aldo Steinfeld} } @article {1004, title = {Solar-to-hydrogen efficiency: shining light on photoelectrochemical device performance}, journal = {Energy \& Environmental Science}, volume = {9}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {74-80}, abstract = {Illumination characteristics from artificial sources strongly influence the experimental performance of solar water-splitting devices, with the highest impact on tandem structures designed for optimum conversion efficiency. We highlight quantitative and qualitative flaws of common characterization techniques, discuss their impact on research results and strategy, and demonstrate approaches toward advanced measurement accuracy.}, issn = {1754-5706}, doi = {10.1039/C5EE03206G}, url = {http://pubs.rsc.org/en/content/articlelanding/2016/ee/c5ee03206g}, author = {H. D{\"o}scher and J. L. Young and J. F. Geisz and J. A. Turner and T. G. Deutsch} } @article {992, title = {Stability of supported platinum sulfuric acid decomposition catalysts for use in thermochemical water splitting cycles}, journal = {International Journal of Hydrogen Energy}, volume = {32}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {482-488}, abstract = {The activity and stability of several metal oxide supported platinum catalysts were explored for the sulfuric acid decomposition reaction. The acid decomposition reaction is common to several sulfur based thermochemical water splitting cycles. Reactions were carried out using a feed of concentrated liquid sulfuric acid (96wt\%) at atmospheric pressure at temperatures between 800 and 850oC and a weight hour space velocity of 52g acid/g catalyst/h. Reactions were run at high space velocities such that variations in kinetics were not masked by surplus catalyst. The influence of exposure to reaction conditions was explored for three catalysts; 0.1{\textendash}0.2wt\% Pt supported on alumina, zirconia and titania. The higher surface area Pt/Al2O3 and Pt/ZrO2 catalysts had the highest activity but deactivated rapidly. A low surface area Pt/TiO2 catalyst had good stability in short term tests, but slowly lost activity for over 200h of continuous operation.}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2006.06.053}, url = {http://www.sciencedirect.com/science/article/pii/S0360319906002655}, author = {Daniel M. Ginosar and Lucia M. Petkovic and Anne W. Glenn and Kyle C. Burch} } @article {752, title = {On the structural stability of crystalline ceria phases in undoped and acceptor-doped ceria materials under in situ reduction conditions}, journal = {Crystengcomm}, volume = {21}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {145-154}, abstract = {The reduction of pure and Sm-doped ceria in hydrogen has been studied by synchrotron-based in situ X-ray diffraction to eventually prove or disprove the presence of crystalline cerium hydride (CeHx) phases and the succession of potential structural phase (trans)formations of reduced cerium oxide phases during heating-cooling cycles up to 1273 K. Despite a recent report on the existence of bulk and surface CeHx phases during reductive treatment of pure CeO2 in H-2, structural analysis by Rietveld refinement as well as additional H-1-NMR spectroscopy did not reveal the presence of any crystalline CeHx phase. Rather, a sequence of phase transformations during the re-cooling process in H-2 has been observed. In both samples, the reduced/defective fluorite lattice undergoes at first a transformation into a bixbyite-type lattice with a formal stoichiometry Ce0.583+Ce0.424+O1.71 and Sm0.153+Ce0.393+Ce0.464+O1.73, before a transformation into rhombohedral Ce7O12 takes place in pure CeO2. This phase is clearly absent for the Sm-doped material. Finally, a triclinic Ce11O20 phase appears for both materials, which can be recovered to room temperature, and on which a phase mixture of bixbyite Ce0.663+Ce0.344+O1.67, rh-Ce0.603+Ce0.404+O1.70 and tri-Ce0.483+Ce0.524+O1.76 (for pure CeO2) or bixbyite Sm0.153+Ce0.473+Ce0.384+O1.69 and tri-Sm0.153+Ce0.313+Ce0.544+O1.77 (for Sm-doped CeO2) prevails. The absence of the rhombohedral phase indicates that Sm doping leads to the stabilization of the bixbyite phase over the rhombohedral one at this particular oxygen vacancy concentration. It is worth noting that recent work proves that hydrogen is indeed incorporated within the structures during the heat treatments, but under the chosen experimental conditions it has apparently no effect on the salient structural principles during reduction.}, issn = {1466-8033}, doi = {10.1039/c8ce01726c}, author = {Maged F. Bekheet and Matthias Gruenbacher and Lukas Schlicker and Albert Gili and Andrew Doran and Jan Dirk Epping and Aleksander Gurlo and Bernhard Kloetzer and Simon Penner} } @article {793, title = {Structure and magnetic properties of Ba5Ce1.25Mn3.75O15, a new 10H-polytype in the Ba{\textendash}Ce{\textendash}Mn{\textendash}O system}, journal = {Journal of Solid State Chemistry}, volume = {198}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {186-191}, issn = {00224596}, doi = {10.1016/j.jssc.2012.10.004}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0022459612006512}, author = {Mario A. Mac{\'\i}as and Olivier Mentr{\'e} and Silviu Colis and Gabriel J. Cuello and Gilles H. Gauthier} } @article {779, title = {Surface structure of coherently strained ceria ultrathin films}, journal = {Physical Review B}, volume = {94}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, issn = {2469-9950, 2469-9969}, doi = {10.1103/PhysRevB.94.205420}, url = {https://link.aps.org/doi/10.1103/PhysRevB.94.205420}, author = {Yezhou Shi and Kevin H. Stone and Zixuan Guan and Matteo Monti and Chuntian Cao and Farid El Gabaly and William C. Chueh and Michael F. Toney} } @article {842, title = {Sustainable hydrocarbon fuels by recycling CO2 and H2O with renewable or nuclear energy}, journal = {Renewable and Sustainable Energy Reviews}, volume = {15}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {1-23}, issn = {13640321}, doi = {10.1016/j.rser.2010.07.014}, url = {http://linkinghub.elsevier.com/retrieve/pii/S1364032110001942}, author = {Christopher Graves and Sune D. Ebbesen and Mogens Mogensen and Klaus S. Lackner} } @article {896, title = {Test operation of a 100kW pilot plant for solar hydrogen production from water on a solar tower}, journal = {Solar Energy}, volume = {85}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {634-644}, issn = {0038092X}, doi = {10.1016/j.solener.2010.04.014}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0038092X10001623}, author = {M. Roeb and J.-P. S{\"a}ck and P. Rietbrock and C. Prahl and H. Schreiber and M. Neises and L. de Oliveira and D. Graf and M. Ebert and W. Reinalter and M. Meyer-Gr{\"u}nefeldt and C. Sattler and A. Lopez and A. Vidal and A. Elsberg and P. Stobbe and D. Jones and A. Steele and S. Lorentzou and C. Pagkoura and A. Zygogianni and C. Agrafiotis and A.G. Konstandopoulos} } @article {879, title = {Thermochemical Cycles for High-Temperature Solar Hydrogen Production}, journal = {Chemical Reviews}, volume = {107}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {4048-4077}, issn = {0009-2665, 1520-6890}, doi = {10.1021/cr050188a}, url = {http://pubs.acs.org/doi/abs/10.1021/cr050188a}, author = {Tatsuya Kodama and Nobuyuki Gokon} } @article {952, title = {Thermochemical reactivity of 5{\textendash}15mol\% Fe, Co, Ni, Mn-doped cerium oxides in two-step water-splitting cycle for solar hydrogen production}, journal = {Thermochimica Acta}, volume = {617}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {179-190}, issn = {00406031}, doi = {10.1016/j.tca.2015.08.036}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0040603115003561}, author = {Nobuyuki Gokon and Toshinori Suda and Tatsuya Kodama} } @article {904, title = {Thermochemical two-step water splitting by internally circulating fluidized bed of NiFe2O4 particles: Successive reaction of thermal-reduction and water-decomposition steps}, journal = {International Journal of Hydrogen Energy}, volume = {36}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {4757-4767}, issn = {03603199}, doi = {10.1016/j.ijhydene.2011.01.076}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0360319911001194}, author = {Nobuyuki Gokon and Tetsuro Mataga and Nobuyuki Kondo and Tatsuya Kodama} } @article {881, title = {Thermochemical Two-Step Water Splitting by ZrO2-supported NixFe3-xO4 for Solar Hydrogen Production}, journal = {Solar Energy}, volume = {82}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {73-79}, issn = {0038092X}, doi = {10.1016/j.solener.2007.03.005}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0038092X07000783}, author = {T. Kodama and N. Gokon and R. Yamamoto} } @article {802, title = {Thermodynamic modeling of the hybrid sulfur (HyS) cycle for hydrogen production}, journal = {Fluid Phase Equilibria}, volume = {460}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {175-188}, abstract = {We have developed a comprehensive thermodynamic model for the ternary system sulfur dioxide~+~sulfuric acid~+~water based on a previously published thermodynamic model of the aqueous sulfuric acid system using the symmetric electrolyte NRTL (eNRTL) activity coefficient model. The eNRTL binary interaction parameters and the chemical equilibrium constants are regressed from experimental SO2 solubility data in aqueous sulfuric acid solutions. The model accurately represents all thermodynamic properties including vapor-liquid equilibrium, liquid-liquid equilibrium, calorimetric properties, and speciation over a wide acid concentration range, from pure water to pure sulfuric acid and pure sulfur dioxide, and temperatures from 273.15 to 393.15 K. The model should be very useful in supporting process research, development, and design of advanced water-splitting processes based on the hybrid sulfur (HyS) cycle.}, issn = {0378-3812}, doi = {10.1016/j.fluid.2017.12.025}, url = {http://www.sciencedirect.com/science/article/pii/S0378381217305095}, author = {Harnoor Kaur and Meng Wang and Maximilian B. Gorensek and Chau-Chyun Chen} } @article {781, title = {Three Oxidation States of Manganese in the Barium Hexaferrite BaFe 12{\textendash} x Mn x O 19}, journal = {Inorganic Chemistry}, volume = {56}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {3861-3866}, issn = {0020-1669, 1520-510X}, doi = {10.1021/acs.inorgchem.6b02688}, url = {http://pubs.acs.org/doi/10.1021/acs.inorgchem.6b02688}, author = {Sandra Nemrava and Denis A. Vinnik and Zhiwei Hu and Martin Valldor and Chang-Yang Kuo and Dmitry A. Zherebtsov and Svetlana A. Gudkova and Chien-Te Chen and Liu Hao Tjeng and Rainer Niewa} } @article {778, title = {Understanding crystallization pathways leading to manganese oxide polymorph formation}, journal = {Nature Communications}, volume = {9}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {2553}, abstract = {Minor variations in synthesis conditions can redirect crystallization pathways through different nonequilibrium intermediates. Here, the authors present a theoretical framework to predict which polymorphs appear during MnO2 precipitation, which is validated by in situ X-ray scattering of reaction progression.}, issn = {2041-1723}, doi = {10.1038/s41467-018-04917-y}, url = {https://www.nature.com/articles/s41467-018-04917-y}, author = {Bor-Rong Chen and Wenhao Sun and Daniil A. Kitchaev and John S. Mangum and Vivek Thampy and Lauren M. Garten and David S. Ginley and Brian P. Gorman and Kevin H. Stone and Gerbrand Ceder and Michael F. Toney and Laura T. Schelhas} } @article {787, title = {Understanding the spectroscopic signatures of Mn valence changes in the valence energy loss spectra of Li-Mn-Ni-O spinel oxides}, journal = {Physical Review Materials}, volume = {1}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, issn = {2475-9953}, doi = {10.1103/PhysRevMaterials.1.074402}, url = {https://link.aps.org/doi/10.1103/PhysRevMaterials.1.074402}, author = {M. K. Kinyanjui and P. Axmann and M. Mancini and G. Gabrielli and P. Balasubramanian and F. Boucher and M. Wohlfahrt-Mehrens and U. Kaiser} }