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Molecular Coatings Improve the Selectivity and Durability of CO₂ Reduction Chalcogenide Photocathodes

Lai, Yungchieh and Watkins, Nicholas B. and Muzzillo, Christopher and Richter, Matthias and Kan, Kevin and Zhou, Lan and Haber, Joel A. and Zakutayev, Andriy and Peters, Jonas C. and Agapie, Theodor and Gregoire, John M. (2022) Molecular Coatings Improve the Selectivity and Durability of CO₂ Reduction Chalcogenide Photocathodes. ACS Energy Letters, 7 (3). pp. 1195-1201. ISSN 2380-8195. doi:10.1021/acsenergylett.1c02762.

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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.

Item Type:Article
Related URLs:
URLURL TypeDescription
Lai, Yungchieh0000-0001-9392-1447
Watkins, Nicholas B.0000-0001-7251-9387
Muzzillo, Christopher0000-0002-6492-0098
Richter, Matthias0000-0003-0091-2045
Zhou, Lan0000-0002-7052-266X
Haber, Joel A.0000-0001-7847-5506
Zakutayev, Andriy0000-0002-3054-5525
Peters, Jonas C.0000-0002-6610-4414
Agapie, Theodor0000-0002-9692-7614
Gregoire, John M.0000-0002-2863-5265
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.
Group:Resnick Sustainability Institute, Liquid Sunlight Alliance
Funding AgencyGrant Number
Department of Energy (DOE)DE-SC0021266
Department of Energy (DOE)DE-AC36-08GO28308
Resnick Sustainability InstituteUNSPECIFIED
Subject Keywords:Coating materials, Additives, Photonics, Cadmium sulfide, Electrodes
Issue or Number:3
Record Number:CaltechAUTHORS:20220301-900116000
Persistent URL:
Official Citation:Molecular Coatings Improve the Selectivity and Durability of CO2 Reduction Chalcogenide Photocathodes. Yungchieh Lai, Nicholas B. Watkins, Christopher Muzzillo, Matthias Richter, Kevin Kan, Lan Zhou, Joel A. Haber, Andriy Zakutayev, Jonas C. Peters, Theodor Agapie, and John M. Gregoire. ACS Energy Letters 2022 7 (3), 1195-1201; DOI: 10.1021/acsenergylett.1c02762
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:113672
Deposited By: George Porter
Deposited On:01 Mar 2022 23:33
Last Modified:22 Mar 2022 20:37

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