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  • Understanding the Photoelectrochemical Properties of Theoretically Predicted Water‐Splitting Catalysts for Effective Materials Discovery
Title: Understanding the Photoelectrochemical Properties of Theoretically Predicted Water‐Splitting Catalysts for Effective Materials Discovery
Abstract

Data‐intensive discovery of water‐splitting catalysts can accelerate the development of sustainable energy technologies, such as the photocatalytic and/or electrocatalytic production of renewable hydrogen fuel. Through computational screening, 13 materials were recently predicted as potential water‐splitting photocatalysts: Cu3NbS4, CuYS2, SrCu2O2, CuGaO2, Na3BiO4,Sr2PbO4, LaCuOS, LaCuOSe, Na2TeO4, La4O4Se3, Cu2WS4, BaCu2O2, and CuAlO2. Herein, these materials are synthesized, their bandgaps and band alignments are experimentally determined, and their photoelectrocatalytic hydrogen evolution properties are assessed. Using cyclic voltammetry and chopped illumination experiments, 9 of the 13 materials are experimentally found to have bandgaps and band alignments that straddle the potentials required for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), as computationally predicted. During photocatalytic testing, 12 of the materials yield a measurable photocurrent. However, only three are found to be active for the HER, with Cu3NbS4, CuYS2, and Cu2WS4producing H2in amounts comparable to bare TiO2; a benchmark photocatalyst. This study provides experimental validation of computational bandgap and band alignment predictions while also successfully identifying active photocatalysts.

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Award ID(s):
1729338
NSF-PAR ID:
10371542
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Energy Materials
Volume:
12
Issue:
46
ISSN:
1614-6832
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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