Molecular Coatings Improve the Selectivity and Durability of CO₂ Reduction Chalcogenide Photocathodes
Abstract
The quest for solar-driven conversion of carbon dioxide to chemicals and fuels hinges upon the identification of an efficient, durable, and selective photocathode. Chalcogenide p-type semiconductors exemplified by chalcopyrite Cu(In,Ga)Se₂ (CIGS) have been effectively deployed as photocathodes. However, selectivity toward CO₂ reduction and durability of the commonly used CdS adlayer remain primary challenges. Here, we demonstrate that for the wide band gap CuGa₃Se₅ chalcopyrite absorber these challenges are well addressed by an organic coating generated in situ from an N,N′-(1,4-phenylene)bispyridinium ditriflate salt in the electrolyte. The molecular additive provides a 30-fold increase in selectivity toward CO₂R products compared to the unmodified system and lowers Cd corrosion at least 10-fold. This dual functionality highlights the promise of hybrid solid-state-molecular photocathodes for enabling durable and efficient solar fuel systems.
Additional Information
© 2022 American Chemical Society. Received 18 December 2021. Accepted 23 February 2022. Published online 1 March 2022. This material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. National Renewable Energy Laboratory is operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. The Resnick Sustainability Institute at Caltech is also acknowledged for its support of enabling infrastructure and facilities. The views expressed in this article do not necessarily represent the views of the DOE or the U.S. Government. The authors declare no competing financial interest.Attached Files
Supplemental Material - nz1c02762_si_001.pdf
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Additional details
- Eprint ID
- 113672
- DOI
- 10.1021/acsenergylett.1c02762
- Resolver ID
- CaltechAUTHORS:20220301-900116000
- Department of Energy (DOE)
- DE-SC0021266
- Department of Energy (DOE)
- DE-AC36-08GO28308
- Resnick Sustainability Institute
- Created
-
2022-03-01Created from EPrint's datestamp field
- Updated
-
2022-03-22Created from EPrint's last_modified field
- Caltech groups
- Resnick Sustainability Institute, Liquid Sunlight Alliance