Vapor Transport Deposition of Sb<sub>2</sub>(S,Se)<sub>3</sub> Solar Cells with Continuously Tunable Band Gaps
Yanlin Pan, Xingyu Pan, Rui Wang, Xiaobo Hu, Shaoqiang Chen, Jiahua Tao, Pingxiong Yang, Junhao Chu
Abstract
Antimony chalcogenide (Sb2(S,Se)3) semiconductors have been demonstrated as a promising absorber material for highly efficient inorganic solar cells. Especially, tunable band gaps make them fascinating in the photovoltaic field, thanks to the reciprocal replacement of Se and S atoms. Herein, a series of Sb2(S,Se)3 films with continuously tunable band gaps were reported through a typical vapor transport deposition process. We concluded the relationship of the Se/S ratio between the evaporation source and the deposited film and successfully modified the structural and optical properties of the deposited Sb2(S,Se)3 films with a regulation of the Se/S ratio in the evaporation source. We found that interfacial diffusion during the deposition process was destructive to the device performance. With an optimization of the band gap, a power conversion efficiency of 7.1% was obtained for the Sb2(S,Se)3 single-junction solar cell. This study proposed a reliable way to achieve various Sb2(S,Se)3 films with designated band gaps for the demand of multijunction solar cells.