@article {1132,
	title = {A Computational Framework to Accelerate the Discovery of Perovskites for Solar Thermochemical Hydrogen Production: Identification of Gd Perovskite Oxide Redox Mediators},
	journal = {Advanced Functional Materials},
	year = {2022},
	pages = {2200201},
	abstract = {A high-throughput computational framework to identify novel multinary perovskite redox mediators is presented, and this framework is applied to discover the Gd-containing perovskite oxide compositions Gd2BB'O6, GdA'B2O6, and GdA'BB'O6 that split water. The computational scheme uses a sequence of empirical approaches to evaluate the stabilities, electronic properties, and oxygen vacancy thermodynamics of these materials, including contributions to the enthalpies and entropies of reduction, ΔHTR and ΔSTR. This scheme uses the machine-learned descriptor τ to identify compositions that are likely stable as perovskites, the bond valence method to estimate the magnitude and phase of BO6 octahedral tilting and provide accurate initial estimates of perovskite geometries, and density functional theory including magnetic- and defect-sampling to predict STCH-relevant properties. Eighty-three promising STCH candidate perovskite oxides down-selected from 4392 Gd-containing compositions are reported, three of which are referred to experimental collaborators for characterization and exhibit STCH activity. The results demonstrate that the high-throughput computational scheme described herein{\textemdash}which is used to evaluate Gd-containing compositions but can be applied to any multinary perovskite oxide compositional space(s) of interest{\textemdash}accelerates the discovery of novel STCH active redox mediators with reasonable computational expense.},
	keywords = {concentrated solar energy, density functional theory, hydrogen, Perovskite, thermochemical water splitting},
	doi = {https://doi.org/10.1002/adfm.202200201},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202200201},
	author = {Bare, Zachary J. L. and Morelock, Ryan J. and Musgrave, Charles B.}
}
@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 BiVO<sub>4</sub> 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 {1153,
	title = {Chalkboard 2 - How to Make Clean Hydrogen},
	journal = {The Electrochemical Society Interface},
	volume = {30},
	year = {2021},
	month = {dec},
	pages = {49{\textendash}56},
	abstract = {Clean hydrogen is a carbon-free energy carrier that can be produced from water and sustainable energy sources such as wind, solar, and nuclear. Hence, clean hydrogen is one of the best ways to not only decarbonize the energy supply system, but also address the zero-emission challenges specific to large-carbon emitting industries that are difficult to separate from fossil fuels. To help achieve the Biden Administration{\textquoteright}s goal of a 100\% clean energy economy and net-zero emissions by 2050, several tens of millions of metric tons of clean, low-cost hydrogen will be needed annually. The HydroGEN Advanced Water Splitting Materials (AWSM) Consortium was established in 2016 as part of the Energy Materials Network (EMN) under the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office to enhance the performance, improve the durability, and reduce the cost of clean hydrogen production technologies, and it is helping to advance the H2@Scale vision.},
	keywords = {Clean hydrogen, decarbonization, energy supply system, hydrogen, zero-emission challenges},
	doi = {10.1149/2.f13214if},
	url = {https://doi.org/10.1149/2.f13214if},
	author = {Shaun Alia and Dong Ding and Anthony McDaniel and Francesca M. Toma and Huyen N. Dinh}
}
@article {1154,
	title = {Effect of Nanoscale Ce0.8Gd0.2O2-δ Infiltrant and Steam Content on Ni{\textendash}(Y2O3)0.08(ZrO2)0.92 Fuel Electrode Degradation during High-Temperature Electrolysis},
	journal = {Nano Letters},
	volume = {21},
	year = {2021},
	note = {PMID: 34606281},
	pages = {8363-8369},
	keywords = {degredation, duel electrode, infiltration, solid oxide electrolysis cell},
	doi = {10.1021/acs.nanolett.1c02937},
	url = {https://doi.org/10.1021/acs.nanolett.1c02937},
	author = {Park, Beom-Kyeong and Cox, Dalton and Barnett, Scott A.}
}
@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 {1157,
	title = {Hydrogen: Targeting \textdollar1/kg in 1 Decade},
	journal = {The Electrochemical Society Interface},
	volume = {30},
	year = {2021},
	month = {12/2021},
	pages = {61{\textendash}66},
	abstract = {The societal energy system is evolving rapidly as the impacts of our existing energy system are better appreciated and technological advances have dramatically decreased the cost of renewable resources. Simultaneously, the importance of energy transfer across timeframes and the difficulty of decarbonizing the industrial loads and transportation demands using electricity are being recognized. At the center of this need is achieving low-cost clean hydrogen. The U.S. Department of Energy launched the Hydrogen Energy EarthShot which seeks to reduce the cost of clean hydrogen to $1 per 1 kilogram in one decade. Reaching the $1/kg goal is dependent on the evolution of the electrical energy system to increase renewable energy deployment and low electricity costs; advances in electrolysis technology and manufacturing readiness; and infrastructure build-out and hydrogen market establishment that results in the ability to make, move, store, and use clean hydrogen economically while spurring job creation.},
	keywords = {Clean hydrogen, decarbonizing, electrolysis, energy storage, energy transfer, hydrogen market, hydrogen shot},
	doi = {10.1149/2.f15214if},
	url = {https://doi.org/10.1149/2.f15214if},
	author = {Bryan S. Pivovar and Mark F. Ruth and Deborah J. Myers and Huyen N. Dinh}
}
@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 {1160,
	title = {Modeling Electrokinetics of Oxygen Electrodes in Solid Oxide Electrolyzer Cells},
	journal = {Journal of The Electrochemical Society},
	volume = {168},
	year = {2021},
	month = {11/2021},
	pages = {114510},
	abstract = {A microscale model is presented in this study to simulate electrode kinetics of the oxygen electrode in a solid oxide electrolyzer cell (SOEC). Two mixed ionic/electronic conducting structures are examined for the oxygen producing electrode in this work: single layer porous lanthanum strontium cobalt ferrite (LSCF), and bilayer LSCF/SCT (strontium cobalt tantalum oxide) structures. A yttrium-stabilized zirconia (YSZ) electrolyte separates the hydrogen and oxygen electrodes, as well as a gadolinium doped-ceria (GDC) buffer layer on the oxygen electrode side. Electrochemical reactions occurring at the two-phase boundaries (2PBs) and three-phase boundaries (3PBs) of single-layer LSCF and bilayer LSCF/SCT oxygen electrodes are modeled under various SOEC voltages with lattice oxygen stoichiometry as the key output. The results reveal that there exists a competition in electrode kinetics between 2PBs and 3PBs, but 3PBs are the primary reactive sites for single-layer LSCF oxygen electrode under high voltages. These locations experience the greatest oxygen stoichiometry variations and are therefore the most likely locations for dimensional changes. By applying an active SCT layer over LSCF, the 2PBs become activated to compete with the 3PBs, thus alleviating oxygen stoichiometry variations and reducing the likelihood of dimensional change. This strategy could reduce lattice structural expansion, proving to be valuable for electrode-electrolyte delamination prevention and will be the focus of future work.},
	keywords = {Barium zirconate, Defect transport, electrode-electrolyte delamination prevention, Faradaic efficiency, lattice oxygen stoichiometry, microscale model, o-SOEC, oxygen electrode, solid oxide electrolyzer cell},
	doi = {10.1149/1945-7111/ac35fc},
	url = {https://doi.org/10.1149/1945-7111/ac35fc},
	author = {Korey Cook and Jacob Wrubel and Zhiwen Ma and Kevin Huang and Xinfang Jin}
}
@article {1161,
	title = {Multiple Reaction Pathways for the Oxygen Evolution Reaction May Contribute to IrO2 (110){\textquoteright}s High Activity},
	journal = {Journal of The Electrochemical Society},
	volume = {168},
	year = {2021},
	month = {02/2021},
	pages = {024506},
	abstract = {Density functional theory calculations in conjunction with statistical mechanical arguments are performed on the rutile IrO2 (110) facet in order to characterize multiple reaction pathways on the surface at the highest active limit (the stoichiometric surface with all metal sites available) and at the lowest active limit (the oxygen-terminated surface). Alternative pathways to the oxygen evolution reaction (OER) are found, with multiple pathways determined at each step of the four proton-coupled electron transfer reaction. Of particular interest is the detailed characterization of a co-adsorption pathway utilizing neighboring, adsorbed O, OH species in order to evolve oxygen; activation energies of this pathway are <0.5 eV and therefore easily surmountable at the high operating potentials of OER. We also determined that surface Ir atoms can potentially participate in deprotonating an OOH* intermediate; the activation energy to this is 0.67 eV on the oxygen-terminated surface. These theoretical findings explain in part the high activity present in iridium oxide catalysts and also provide insight into the mechanistic pathways available on metal oxide catalysts, which may require the concerted interaction of nearest neighbor co-adsorbates to produce chemicals of interest.},
	keywords = {DFT modeling, Iridium oxide, Oxygen evolution},
	doi = {10.1149/1945-7111/abdeea},
	url = {https://doi.org/10.1149/1945-7111/abdeea},
	author = {Mai-Anh Ha and Ross E. Larsen}
}
@article {1166,
	title = {The oxygen partial pressure in solid oxide electrolysis cells with multilayer electrolytes},
	journal = {Acta Materialia},
	volume = {213},
	year = {2021},
	pages = {116928},
	abstract = {A number of degradation mechanisms have been observed during the long-term operation of solid oxide electrolysis cells (SOEC). Using an electrolyte charge carrier transport model and a diffuse interface treatment for a multilayer electrolytes, we quantify the oxygen potentials across the electrolyte and thereby provide insights into these degradation mechanisms. Our model describes the transport of charge carriers in the electrolyte when the oxygen partial pressure is extremely low by accounting for the spatial variation of the concentration of oxygen vacancies in the electrolyte which is closely related to the degradation of the SOEC near the interface of hydrogen electrode and electrolyte. Moreover, we identify four quantities that characterize the distribution of oxygen partial pressure in the electrolyte, which are directly related to the degradation mechanisms in the electrolyte as well, and give analytical estimates for them. These analytical expressions provide guidance on the parameters that need to be controlled to suppress the degradation observed in the electrolyte.},
	keywords = {Diffuse interface model, Multilayer electrolyte, Oxygen partial pressure, solid oxide electrolysis cell},
	issn = {1359-6454},
	doi = {https://doi.org/10.1016/j.actamat.2021.116928},
	url = {https://www.sciencedirect.com/science/article/pii/S1359645421003086},
	author = {Qian Zhang and Qin-Yuan Liu and Beom-Kyeong Park and Scott Barnett and Peter Voorhees}
}
@article {1169,
	title = {Degradation of solid oxide electrolysis cells: Phenomena, mechanisms, and emerging mitigation strategies{\textemdash}A review},
	journal = {Journal of Materials Science \& Technology},
	volume = {55},
	year = {2020},
	note = {SI: Energy Conversion \& Storage Materials Design, Fabrication and Functionality},
	pages = {35-55},
	abstract = {Solid oxide electrolysis cell (SOEC) is a promising electrochemical device with high efficiency for energy storage and conversion. However, the degradation of SOEC is a significant barrier to commercial viability. In this review paper, the typical degradation phenomena of SOEC are summarized, with great attention into the anodes/oxygen electrodes, including the commonly used and newly developed anode materials. Meanwhile, mechanistic investigations on the electrode/electrolyte interfaces are provided to unveil how the intrinsic factor, oxygen partial pressure pO2, and the electrochemical operation conditions, affect the interfacial stability of SOEC. At last, this paper also presents some emerging mitigation strategies to circumvent long-term degradation, which include novel infiltration method, development of new anode materials and engineering of the microstructure.},
	keywords = {Degradation, Electrode/electrolyte interface, Mitigation, solid oxide electrolysis cell, Strategy},
	issn = {1005-0302},
	doi = {https://doi.org/10.1016/j.jmst.2019.07.026},
	url = {https://www.sciencedirect.com/science/article/pii/S1005030219302464},
	author = {Yi Wang and Wenyuan Li and Liang Ma and Wei Li and Xingbo Liu}
}
@article {1170,
	title = {Emergent Degradation Phenomena Demonstrated on Resilient, Flexible, and Scalable Integrated Photoelectrochemical Cells},
	journal = {Advanced Energy Materials},
	volume = {10},
	year = {2020},
	pages = {2002706},
	abstract = {Abstract Photoelectrochemical (PEC) water splitting provides a pathway to generate sustainable clean fuels using the two most abundant resources on Earth: sunlight and water. Currently, most of the successful models of PEC cells are still fabricated on small scales near 1 cm2, which largely limits the mass deployment of solar-fuel production. Here, the scale-up to 8 cm2 of an integrated PEC (IPEC) device is demonstrated and its performance compared to a 1 cm2 IPEC cell, using state-of-the-art iridium and platinum catalysts with III{\textendash}V photoabsorbers. The initial photocurrents at 1 sun are 8 and 7 mA cm-2 with degradation rates of 0.60 and 0.47 mA cm-2 day-1, during unbiased operation for the 1 and 8 cm2 devices, respectively. Evaluating under outdoor and indoor conditions at two U.S. National Laboratories reveals similar results, evidencing the reproducibility of this design{\textquoteright}s performance. Furthermore, the emerging degradation mechanisms during scale-up are investigated and the knowledge gained from this work will provide feedback to the broader community, since PEC device durability is a limiting factor in its potential future deployment.},
	keywords = {durability, on-sun testing, PEC cell scale-up, reproducibility, water splitting},
	doi = {https://doi.org/10.1002/aenm.202002706},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.202002706},
	author = {Kistler, Tobias A. and Zeng, Guosong and Young, James L. and Weng, Lien-Chun and Aldridge, Chase and Wyatt, Keenan and Steiner, Myles A. and Solorzano Jr., Oscar and Houle, Frances A. and Toma, Francesca M. and Weber, Adam Z. and Deutsch, Todd G. and Danilovic, Nemanja}
}
@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 {1184,
	title = {Effect of direct-current operation on the electrochemical performance and structural evolution of Ni-YSZ electrodes},
	journal = {Journal of Physics: Energy},
	volume = {2},
	year = {2019},
	month = {12/2019},
	pages = {014006},
	abstract = {The effect of electrolysis operations on Ni-YSZ fuel electrode stability was studied at different current densities and fuel mixtures during 1000 h life tests. For a typical electrolysis mixture of 50\% H2/50\% H2O and 0.6 A cm-2 current density, cell ohmic resistance values were reasonably stable and no structural changes occurred. However, for more reducing conditions (97\% H2/3\% H2O), increasing the current density above 0.4 A cm-2 increased the ohmic resistance accompanied by significant electrolyte degradation including fracture and void formation at grain boundaries. Numerical analysis was carried out to determine the effective oxygen partial pressure across the electrolyte. The results show that the oxygen partial pressure values at high current density and low steam content may be low enough to reduce zirconia to form a Ni-Zr alloy product, initiating the observed electrolyte structural degradation.},
	keywords = {durability, HTE, SOEC, Yttria-stabilized zirconia},
	doi = {10.1088/2515-7655/ab59a6},
	url = {https://doi.org/10.1088/2515-7655/ab59a6},
	author = {Qinyuan Liu and Qian Zhang and Peter W Voorhees and Scott A Barnett}
}
@article {1185,
	title = {Ferritic stainless steel interconnects for protonic ceramic electrochemical cell stacks: Oxidation behavior and protective coatings},
	journal = {International Journal of Hydrogen Energy},
	volume = {44},
	year = {2019},
	pages = {25297-25309},
	abstract = {Protonic ceramic fuel or electrolysis cells (PCFC/PCEC) have shown promising performance at intermediate temperatures. However, these technologies have not yet been demonstrated in a stack, hence the oxidation behavior of the metallic interconnect under relevant operating environments is unknown. In this work, ferritic stainless steels 430 SS, 441 SS, and Crofer 22 APU were investigated for their use as interconnect materials in the PCFC/PCEC stack. The bare metal sheets were exposed to a humidified air environment in the temperature range from 450~{\textdegree}C to 650~{\textdegree}C, to simulate their application in a PCFC cathode or PCEC anode. Breakaway oxidation with rapid weight gain and Fe outward diffusion/oxidation was observed on all the selected stainless steel materials. A protective coating is deemed necessary to prevent the metallic interconnect from oxidizing. To mitigate the observed breakaway oxidation, state-of-the-art protective coatings, Y2O3, Ce0.02Mn1.49Co1.49O4, CuMn1.8O4 and Ce/Co, were applied to the stainless steel sheets and their oxidation resistance was investigated. Dual atmosphere testing further validated the effectiveness of the protective coatings in realistic PCFC/PCEC environments, with a hydrogen gradient across the interconnect. Several combinations of metal and coating material were found to be viable for use as the interconnect for PCFC/PCEC stacks.},
	keywords = {Dual atmosphere, Interconnect oxidation, Oxidation, Protective coatings, Protonic ceramic electrolysis cell, Protonic ceramic fuel cell},
	issn = {0360-3199},
	doi = {https://doi.org/10.1016/j.ijhydene.2019.08.041},
	url = {https://www.sciencedirect.com/science/article/pii/S0360319919329581},
	author = {Ruofan Wang and Zhihao Sun and Jung-Pyung Choi and Soumendra N. Basu and Jeffry W. Stevenson and Michael C. Tucker}
}
@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 {1187,
	title = {Interfacial engineering of gallium indium phosphide photoelectrodes for hydrogen evolution with precious metal and non-precious metal based catalysts},
	journal = {Journal of Materials Chemistry A},
	volume = {7},
	year = {2019},
	pages = {16821-16832},
	abstract = {Gallium indium phosphide (GaInP2) is a semiconductor with promising optical and electronic properties to serve as the large bandgap, top junction in a dual absorber tandem solar water splitting device. Poor intrinsic catalytic ability and surface corrosion in aqueous electrolyte remain key obstacles. Significant progress has been made developing thin-film protection layers and active catalysts for photoelectrochemical devices, but combining these into a catalytic protection layer that can provide long-term stability without sacrificing performance has proven difficult due, in large part, to challenges in developing active and stable interfaces. In this work, we demonstrate that a nanoscale molybdenum disulfide (MoS2) film functions both as an effective protection layer and excellent hydrogen evolution catalyst for GaInP2 photocathodes, with only a \~{}10\% loss in initial light-limited current density after 100 h, and a photocurrent onset potential better than that of the same state-of-the-art device with a platinum{\textendash}ruthenium catalyst. Using transient photoreflectance spectroscopy, we probed the carrier dynamics of these photocathodes and show that the MoS2 coated device exhibits improved electron transfer at the surface interface compared to the PtRu catalyzed device. These MoS2 protected devices are among the most active and stable single-absorber photocathodes for solar water splitting to date and offer a promising pathway towards generating hydrogen with high efficiency and significant longevity.},
	keywords = {durability, GaInP2, III-V, MoS2 hydrogen evolution catalyst, MoS2 protective coating, PEC, Photocathode},
	doi = {10.1039/C9TA05247J},
	url = {http://dx.doi.org/10.1039/C9TA05247J},
	author = {Britto, Reuben J. and Young, James L. and Yang, Ye and Steiner, Myles A. and LaFehr, David T. and Friedman, Daniel J. and Beard, Mathew and Deutsch, Todd G. and Jaramillo, Thomas F.}
}
@article {1188,
	title = {Long-term stability studies of a semiconductor photoelectrode in three-electrode configuration},
	journal = {Journal of Materials Chemistry A},
	volume = {7},
	year = {2019},
	pages = {27612-27619},
	abstract = {Improving the stability of semiconductor materials is one of the major challenges for sustainable and economic photoelectrochemical water splitting. N-terminated GaN nanostructures have emerged as a practical protective layer for conventional high efficiency but unstable Si and III{\textendash}V photoelectrodes due to their near-perfect conduction band-alignment, which enables efficient extraction of photo-generated electrons, and N-terminated surfaces, which protects against chemical and photo-corrosion. Here, we demonstrate that Pt-decorated GaN nanostructures on an n+{\textendash}p Si photocathode can exhibit an ultrahigh stability of 3000 h (i.e., over 500 days for usable sunlight \~{}5.5 h per day) at a large photocurrent density (>35 mA cm-2) in three-electrode configuration under AM 1.5G one-sun illumination. The measured applied bias photon-to-current efficiency of 11.9\%, with an excellent onset potential of \~{}0.56 V vs. RHE, is one of the highest values reported for a Si photocathode under AM 1.5G one-sun illumination. This study provides a paradigm shift for the design and development of semiconductor photoelectrodes for PEC water splitting: stability is no longer limited by the light absorber, but rather by co-catalyst particles.},
	keywords = {durability, GaN nanowires, PEC, Photocathode, Pt hydrogen evolution catalyst, Silicon},
	doi = {10.1039/C9TA09926C},
	url = {http://dx.doi.org/10.1039/C9TA09926C},
	author = {Vanka, Srinivas and Sun, Kai and Zeng, Guosong and Pham, Tuan Anh and Toma, Francesca Maria and Ogitsu, Tadashi and Mi, Zetian}
}
@article {1190,
	title = {Photoelectrochemical water splitting using strain-balanced multiple quantum well photovoltaic cells},
	journal = {Sustainable Energy Fuels},
	volume = {3},
	year = {2019},
	pages = {2837-2844},
	abstract = {Starting from the classical GaInP/GaAs tandem photoelectrochemical water splitting device, higher solar-to-hydrogen efficiencies can be pursued by extending photon absorption to longer wavelengths. We incorporate strain-balanced GaInAs/GaAsP quantum wells into the bottom GaAs junction, to increase the range of photon absorption. The inclusion of 1.34 eV quantum wells in the depletion region of the bottom cell extends the absorption edge to 930 nm. With a corresponding increase in the thickness of the top cell for current matching, the light-limiting photocurrent increases by >8\%. The estimated solar-to-hydrogen efficiency is 13.6 {\textpm} 0.5\%, and we show a pathway to further improvement. With the semiconductor device remaining on the growth substrate, this quantum well architecture may enable improved stability and durability of the photoelectrochemical electrodes.},
	keywords = {durability, National Renewable Energy Lab (NREL), PEC, photoelectrochemical water splitting},
	doi = {10.1039/C9SE00276F},
	url = {http://dx.doi.org/10.1039/C9SE00276F},
	author = {Steiner, Myles A. and Barraugh, Collin D. and Aldridge, Chase W. and Alvarez, Isabel Barraza and Friedman, Daniel J. and Ekins-Daukes, Nicholas J. and Deutsch, Todd G. and Young, James L.}
}
@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}
}
