Low-Temperature Solution-Processed Kesterite Solar Cell Based on in Situ Deposition of Ultrathin Absorber Layer.
The production of high-performance, solution-processed kesterite Cu2ZnSn(Sx,Se1-x)4 (CZTSSe) solar cells typically relies on high-temperature crystallization processes in chalcogen-containing atmosphere and often on the use of environmentally harmful solvents, which could hinder the widespread adoption of this technology. We report a method for processing selenium free Cu2ZnSnS4 (CZTS) solar cells based on a short annealing step at temperatures as low as 350 °C using a molecular based precursor, fully avoiding highly toxic solvents and high-temperature sulfurization. We show that a simple device structure consisting of ITO/CZTS/CdS/Al and comprising an extremely thin absorber layer (∼110 nm) achieves a current density of 8.6 mA/cm(2). Over the course of 400 days under ambient conditions encapsulated devices retain close to 100% of their original efficiency. Using impedance spectroscopy and photoinduced charge carrier extraction by linearly increasing voltage (photo-CELIV), we demonstrate that reduced charge carrier mobility is one limiting parameter of low-temperature CZTS photovoltaics. These results may inform less energy demanding strategies for the production of CZTS optoelectronic layers compatible with large-scale processing techniques.
Institute of Materials for Electronics and Energy Technology (I-MEET), Department of Materials Science and Engineering, Friedrich-Alexander University Erlangen-Nuremberg , Martensstrasse 7, 91058 Erlangen, Germany.|Erlangen Graduate School in Advanced Optical Technologies (SAOT) , Paul-Gordan-Strasse 6, 91052 Erlangen, Germany.
Yi
Y
Hou
Institute of Materials for Electronics and Energy Technology (I-MEET), Department of Materials Science and Engineering, Friedrich-Alexander University Erlangen-Nuremberg , Martensstrasse 7, 91058 Erlangen, Germany.
Hamed
H
Azimi
Institute of Materials for Electronics and Energy Technology (I-MEET), Department of Materials Science and Engineering, Friedrich-Alexander University Erlangen-Nuremberg , Martensstrasse 7, 91058 Erlangen, Germany.
Nicola
N
Gasparini
Institute of Materials for Electronics and Energy Technology (I-MEET), Department of Materials Science and Engineering, Friedrich-Alexander University Erlangen-Nuremberg , Martensstrasse 7, 91058 Erlangen, Germany.|Instituto de Telecomunicações, Instituto Superior Técnico , Av. RoviscoPais, P-1049-001 Lisboa, Portugal.
Michael
M
Salvador
Institute of Materials for Electronics and Energy Technology (I-MEET), Department of Materials Science and Engineering, Friedrich-Alexander University Erlangen-Nuremberg , Martensstrasse 7, 91058 Erlangen, Germany.|Erlangen Graduate School in Advanced Optical Technologies (SAOT) , Paul-Gordan-Strasse 6, 91052 Erlangen, Germany.
Wei
W
Chen
Institute of Materials for Electronics and Energy Technology (I-MEET), Department of Materials Science and Engineering, Friedrich-Alexander University Erlangen-Nuremberg , Martensstrasse 7, 91058 Erlangen, Germany.|Department of Metallurgical Engineering, NED University of Engineering and Technology , University Road, Karachi 75270, Pakistan.
Laraib S
LS
Khanzada
Chair for Crystallography and Structural Physics, Friedrich-Alexander-University Erlangen-Nürnberg , Staudtstrasse 3, 91058 Erlangen, Germany.
Marco
M
Brandl
Chair for Crystallography and Structural Physics, Friedrich-Alexander-University Erlangen-Nürnberg , Staudtstrasse 3, 91058 Erlangen, Germany.
Rainer
R
Hock
Institute of Materials for Electronics and Energy Technology (I-MEET), Department of Materials Science and Engineering, Friedrich-Alexander University Erlangen-Nuremberg , Martensstrasse 7, 91058 Erlangen, Germany.|Bavarian Center for Applied Energy Research (ZAE Bayern) , Haberstrasse 2a, 91058 Erlangen, Germany.
Christoph J
CJ
Brabec
CZTS; device stability; kesterite solar cells; low-temperature processing; molecular based precursor