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Title: Hybrid Composite Coatings for Durable and Efficient Solar Hydrogen Generation under Diverse Operating Conditions

Abstract

Safe and practical solar-driven hydrogen generators must be capable of efficient and stable operation under diurnal cycling with full separation of gaseous H 2 and O 2 products. In this paper, a novel architecture that fulfills all of these requirements is presented. The approach is inherently scalable and provides versatility for operation under diverse electrolyte and lighting conditions. The concept is validated using a 1 cm 2 triple-junction photovoltaic cell with its illuminated photocathode protected by a composite coating comprising an organic encapsulant with an embedded catalytic support. The device is compatible with operation under conditions ranging from 1 M H 2SO 4 to 1 M KOH, enabling flexibility in selection of semiconductor, electrolyte, membrane, and catalyst. Stable operation at a solar-to-hydrogen conversion efficiency of >10% is demonstrated under continuous operation, as well as under diurnal light cycling for at least 4 d, with simulated sunlight. Operational characteristics are validated by extended time outdoor testing. A membrane ensures products are separated, with nonexplosive gas streams generated for both alkaline and acidic systems. Finally, analysis of operational characteristics under different lighting conditions is enabled by comparison of a device model to experimental data.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1379904
Alternate Identifier(s):
OSTI ID: 1398282
Grant/Contract Number:
AC02-05CH11231; SC0004993
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Advanced Energy Materials
Additional Journal Information:
Journal Volume: 7; Journal Issue: 13; Journal ID: ISSN 1614-6832
Publisher:
Wiley
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 14 SOLAR ENERGY; corrosion protection; high efficiency; hybrid composites; outdoor testing; solar water splitting

Citation Formats

Walczak, Karl A., Segev, Gideon, Larson, David M., Beeman, Jeffrey W., Houle, Frances A., and Sharp, Ian D. Hybrid Composite Coatings for Durable and Efficient Solar Hydrogen Generation under Diverse Operating Conditions. United States: N. p., 2017. Web. doi:10.1002/aenm.201602791.
Walczak, Karl A., Segev, Gideon, Larson, David M., Beeman, Jeffrey W., Houle, Frances A., & Sharp, Ian D. Hybrid Composite Coatings for Durable and Efficient Solar Hydrogen Generation under Diverse Operating Conditions. United States. doi:10.1002/aenm.201602791.
Walczak, Karl A., Segev, Gideon, Larson, David M., Beeman, Jeffrey W., Houle, Frances A., and Sharp, Ian D. Fri . "Hybrid Composite Coatings for Durable and Efficient Solar Hydrogen Generation under Diverse Operating Conditions". United States. doi:10.1002/aenm.201602791. https://www.osti.gov/servlets/purl/1379904.
@article{osti_1379904,
title = {Hybrid Composite Coatings for Durable and Efficient Solar Hydrogen Generation under Diverse Operating Conditions},
author = {Walczak, Karl A. and Segev, Gideon and Larson, David M. and Beeman, Jeffrey W. and Houle, Frances A. and Sharp, Ian D.},
abstractNote = {Safe and practical solar-driven hydrogen generators must be capable of efficient and stable operation under diurnal cycling with full separation of gaseous H2 and O2 products. In this paper, a novel architecture that fulfills all of these requirements is presented. The approach is inherently scalable and provides versatility for operation under diverse electrolyte and lighting conditions. The concept is validated using a 1 cm2 triple-junction photovoltaic cell with its illuminated photocathode protected by a composite coating comprising an organic encapsulant with an embedded catalytic support. The device is compatible with operation under conditions ranging from 1 M H2SO4 to 1 M KOH, enabling flexibility in selection of semiconductor, electrolyte, membrane, and catalyst. Stable operation at a solar-to-hydrogen conversion efficiency of >10% is demonstrated under continuous operation, as well as under diurnal light cycling for at least 4 d, with simulated sunlight. Operational characteristics are validated by extended time outdoor testing. A membrane ensures products are separated, with nonexplosive gas streams generated for both alkaline and acidic systems. Finally, analysis of operational characteristics under different lighting conditions is enabled by comparison of a device model to experimental data.},
doi = {10.1002/aenm.201602791},
journal = {Advanced Energy Materials},
number = 13,
volume = 7,
place = {United States},
year = {Fri Feb 17 00:00:00 EST 2017},
month = {Fri Feb 17 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 2works
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