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Title: Effects of thermochemical treatment on CuSbS 2 photovoltaic absorber quality and solar cell reproducibility

Abstract

CuSbS 2 is a promising nontoxic and earth-abundant photovoltaic absorber that is chemically simpler than the widely studied Cu 2ZnSnS 4. However, CuSbS 2 photovoltaic (PV) devices currently have relatively low efficiency and poor reproducibility, often due to suboptimal material quality and insufficient optoelectronic properties. To address these issues, here we develop a thermochemical treatment (TT) for CuSbS 2 thin films, which consists of annealing in Sb 2S 3 vapor followed by a selective KOH surface chemical etch. The annealed CuSbS 2 films show improved structural quality and optoelectronic properties, such as stronger band-edge photoluminescence and longer photoexcited carrier lifetime. These improvements also lead to more reproducible CuSbS 2 PV devices, with performance currently limited by a large cliff-type interface band offset with CdS contact. Altogether, these results point to the potential avenues to further increase the performance of CuSbS 2 thin film solar cell, and the findings can be transferred to other thin film photovoltaic technologies.

Authors:
 [1];  [2];  [2];  [3];  [4];  [4];  [4];  [5];  [5];  [6];  [3]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States); Federal Univ. of Sao Carlos, Sao Carlos (Brazil)
  2. National Renewable Energy Lab. (NREL), Golden, CO (United States); Colorado School of Mines, Golden, CO (United States)
  3. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  4. Helmholtz Zentrum Berlin fur Materialien und Energie GmbH, Berlin (Germany)
  5. Forschungszentrum Juelich GmbH, Juelich (Germany)
  6. Federal Univ. of Sao Carlos, Sao Carlos (Brazil)
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
OSTI Identifier:
1319282
Report Number(s):
NREL/JA-5K00-66168
Journal ID: ISSN 1932-7447
Grant/Contract Number:
AC36-08GO28308
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Physical Chemistry. C
Additional Journal Information:
Journal Volume: 120; Journal Issue: 33; Journal ID: ISSN 1932-7447
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; photovoltaic absorbers; copper antimony sulfide; thermochemical treatment

Citation Formats

de Souza Lucas, Francisco Willian, Welch, Adam W., Baranowski, Lauryn L., Dippo, Patricia C., Hempel, Hannes, Unold, Thomas, Eichberger, Rainer, Blank, Beatrix, Rau, Uwe, Mascaro, Lucia H., and Zakutayev, Andriy. Effects of thermochemical treatment on CuSbS2 photovoltaic absorber quality and solar cell reproducibility. United States: N. p., 2016. Web. doi:10.1021/acs.jpcc.6b04206.
de Souza Lucas, Francisco Willian, Welch, Adam W., Baranowski, Lauryn L., Dippo, Patricia C., Hempel, Hannes, Unold, Thomas, Eichberger, Rainer, Blank, Beatrix, Rau, Uwe, Mascaro, Lucia H., & Zakutayev, Andriy. Effects of thermochemical treatment on CuSbS2 photovoltaic absorber quality and solar cell reproducibility. United States. doi:10.1021/acs.jpcc.6b04206.
de Souza Lucas, Francisco Willian, Welch, Adam W., Baranowski, Lauryn L., Dippo, Patricia C., Hempel, Hannes, Unold, Thomas, Eichberger, Rainer, Blank, Beatrix, Rau, Uwe, Mascaro, Lucia H., and Zakutayev, Andriy. 2016. "Effects of thermochemical treatment on CuSbS2 photovoltaic absorber quality and solar cell reproducibility". United States. doi:10.1021/acs.jpcc.6b04206. https://www.osti.gov/servlets/purl/1319282.
@article{osti_1319282,
title = {Effects of thermochemical treatment on CuSbS2 photovoltaic absorber quality and solar cell reproducibility},
author = {de Souza Lucas, Francisco Willian and Welch, Adam W. and Baranowski, Lauryn L. and Dippo, Patricia C. and Hempel, Hannes and Unold, Thomas and Eichberger, Rainer and Blank, Beatrix and Rau, Uwe and Mascaro, Lucia H. and Zakutayev, Andriy},
abstractNote = {CuSbS2 is a promising nontoxic and earth-abundant photovoltaic absorber that is chemically simpler than the widely studied Cu2ZnSnS4. However, CuSbS2 photovoltaic (PV) devices currently have relatively low efficiency and poor reproducibility, often due to suboptimal material quality and insufficient optoelectronic properties. To address these issues, here we develop a thermochemical treatment (TT) for CuSbS2 thin films, which consists of annealing in Sb2S3 vapor followed by a selective KOH surface chemical etch. The annealed CuSbS2 films show improved structural quality and optoelectronic properties, such as stronger band-edge photoluminescence and longer photoexcited carrier lifetime. These improvements also lead to more reproducible CuSbS2 PV devices, with performance currently limited by a large cliff-type interface band offset with CdS contact. Altogether, these results point to the potential avenues to further increase the performance of CuSbS2 thin film solar cell, and the findings can be transferred to other thin film photovoltaic technologies.},
doi = {10.1021/acs.jpcc.6b04206},
journal = {Journal of Physical Chemistry. C},
number = 33,
volume = 120,
place = {United States},
year = 2016,
month = 8
}

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