Laboratory and On-Sun PEC Device Testing


Lawrence Berkeley National Laboratory (LBNL)

Capability Expert

Francesca Toma, Frances Houle, Nemanja Danilovic



Node Readiness Category

1: Photoelectrochemical (PEC)


Previous capability name: "Water Splitting Device Testing" and "Outdoor Testing Facility for Solar Water Splitting Devices."

LBNL has capabilities to evaluate electrochemical and photoelectrochemical (PEC) properties of (photo)electrocatalysts, and complete cells, in laboratory and on-sun conditions.

PEC Device and Materials Testing


A prototyping laboratory equipped with a full suite of instruments for testing, characterizing, and benchmarking photoelectrochemical water splitting systems. In addition to conventional half-cell measurements in aqueous conditions, two additional types of PEC test beds have been developed for integrating and testing PEC materials: electrocatalysts, barrier layers, photoabsorbers, photovoltaics, and membranes. The grid cell1,2 is a liquid electrolyte cell, while the channel cell3 can be used with liquid water or water vapor. The facility includes an Oriel Sol3A Large Solar Simulator (model: SP94123A-5354, vendor: Newport), a gas chromatograph for gas purity evaluations (model: 7890B, vendor: Agilent), an inverted burette system for measuring gas volume, a potentiostat, a computer system and video camera for recording test results, and a calibrated photodetector for monitoring irradiation intensity.

On-Sun Testing

Toma, Danilovic; POC:

Fully portable facility designed for conducting real-world field tests of PEC cells. It consists of a STR-22G Sun Tracker, solar tracker assembly, sample mount, and weatherized data acquisition hardware in a portable chassis. The mount is designed to hold a PEC cell for continuous, unattended, solar-driven PEC operation. The sun tracker has an integrated sun sensor as well as GPS locator to assess device performance under natural daylight with diurnal cycling. PEC cells mounted on the tracker can be tested indefinitely and continuously by adjusting the sampling rate.

Capability Bounds‎

For PEC: Currently 5 cm x 5 cm cells with 1–2 cm devices, maximum to be determined by the solar simulator lens diameter (approximately 12 inches). For on-sun testing, various cell sizes can be accommodated up to 20 kg and a total current of 3 A. 

Unique Aspects‎

Capability enables complete data capture for devices under AM 1.5G illumination as well as integrated flow measurements and custom lab view programming for remote control of test stations. The on-sun instrument combines multiple simultaneous performance metrics to assess PEC device properties in use and thus benchmark their on-sun real-world performance. This includes potentiostat for j-V measurements, gas permeation setup for faradaic efficiency measurement, cell temperature monitoring, and reference cell for correlating device illumination.


Facilities are in use for current studies but can accommodate additional projects.


This capability would be central to testing of integrated photoelectrochemical devices for water splitting.


Close up view of the PEC water splitting device and photodetector on a laboratory benchtop

Figure 1. This photograph shows a PEC water splitting device (left) next to a photodetector for monitoring light source output

Schematic of the channel cell components and a graph showing solar-to-hydrogen conversion performance of the cell over 100 hours

Figure 2. Channel cell3 operating under vapor-fed conditions with no liquid electrolyte

Two images show an on-sun test stand sitting on a desk on a grass-covered rooftop, and a closeup view of the on-sun test stand.

Figure 3. On-sun test stand on roof of Building 30 lawn, LBNL1


  1. Karl Walczak, Yikai Chen, Christoph Karp, Jeffrey W. Beeman, Matthew Shaner, Joshua Spurgeon, Ian D. Sharp, Xenia Amashukeli, William West, Jian Jin, Nathan S. Lewis, and Chengxiang Xiang, "Modeling, Simulation, and Fabrication of a Fully Integrated, Acid-stable, Scalable Solar-Driven Water-Splitting System," ChemSusChem 8 (2015): 544–551.
  2. J. Jin et al, "An experimental and modeling/simulation-based evaluation of the efficiency and operational performance characteristics of an integrated, membrane-free, neutral pH solar-driven water-splitting system," Energy and Environmental Science 7 (2014): 3371–3380, DOI: 10.1039/c4ee01824a (2014).
  3. Tobias A. Kistler, David Larson, Karl Walczak, Peter Agbo, Ian D. Sharp, Adam Z. Weber, Nemanja Danilovic, "Integrated Membrane-Electrode-Assembly Photoelectrochemical Cell under Various Feed Conditions for Solar Water Splitting," J. Electrochem. Soc. 166, no. 5 (2019): H3020–H3028.