A Simple Aqueous Precursor Solution Processing of Earth-Abundant Cu2SnS3 Absorbers for Thin-Film Solar Cells.
A simple and eco-friendly method of solution processing of Cu2SnS3 (CTS) absorbers using an aqueous precursor solution is presented. The precursor solution was prepared by mixing metal salts into a mixture of water and ethanol (5:1) with monoethanolamine as an additive at room temperature. Nearly carbon-free CTS films were formed by multispin coating the precursor solution and heat treating in air followed by rapid thermal annealing in S vapor atmosphere at various temperatures. Exploring the role of the annealing temperature in the phase, composition, and morphological evolution is essential for obtaining highly efficient CTS-based thin film solar cells (TFSCs). Investigations of CTS absorber layers annealed at various temperatures revealed that the annealing temperature plays an important role in further improving device properties and efficiency. A substantial improvement in device efficiency occurred only at the critical annealing temperature, which produces a compact and void-free microstructure with large grains and high crystallinity as a pure-phase absorber layer. Finally, at an annealing temperature of 600 °C, the CTS thin film exhibited structural, compositional, and microstructural isotropy by yielding a reproducible power conversion efficiency of 1.80%. Interestingly, CTS TFSCs exhibited good stability when stored in an air atmosphere without encapsulation at room temperature for 3 months, whereas the performance degraded slightly when subjected to accelerated aging at 80 °C for 100 h under normal laboratory conditions.
Department of Materials Science and Engineering and Optoelectronics Convergence Research Center, Chonnam National University , 300, Yongbong-Dong, Buk-Gu, Gwangju 500-757, South Korea.
Mahesh P
MP
Suryawanshi
Department of Materials Science and Engineering and Optoelectronics Convergence Research Center, Chonnam National University , 300, Yongbong-Dong, Buk-Gu, Gwangju 500-757, South Korea.
Uma V
UV
Ghorpade
Department of Chemical Engineering and Materials Science, University of Minnesota , Amundson Hall, 421 Washington Avenue Southeast, Minneapolis, Minnesota 55455-0132, United States.
Seung Wook
SW
Shin
Department of Materials Science and Engineering and Optoelectronics Convergence Research Center, Chonnam National University , 300, Yongbong-Dong, Buk-Gu, Gwangju 500-757, South Korea.
Sachin A
SA
Pawar
Gwangju Institute of Science and Technology, Cheomdangwagi-ro, Buk-gu, Gwangju 500-712, South Korea.
In Young
IY
Kim
Department of Materials Science and Engineering and Optoelectronics Convergence Research Center, Chonnam National University , 300, Yongbong-Dong, Buk-Gu, Gwangju 500-757, South Korea.
Chang Woo
CW
Hong
Department of Materials Science and Engineering and Optoelectronics Convergence Research Center, Chonnam National University , 300, Yongbong-Dong, Buk-Gu, Gwangju 500-757, South Korea.
Minhao
M
Wu
Thin Film Nanomaterials Laboratory, Department of Physics, Shivaji University , Kolhapur, Maharashtra 416004, India.
Pramod S
PS
Patil
Thin Film Nanomaterials Laboratory, Department of Physics, Shivaji University , Kolhapur, Maharashtra 416004, India.
Annasaheb V
AV
Moholkar
Department of Materials Science and Engineering and Optoelectronics Convergence Research Center, Chonnam National University , 300, Yongbong-Dong, Buk-Gu, Gwangju 500-757, South Korea.
Jin Hyeok
JH
Kim
Cu2SnS3 (CTS); aqueous precursor solution processing; device stability; diode analysis; thin films solar cells (TFSCs)