Quasi-Vertically Oriented Sb2Se3 Thin-Film Solar Cells with Open-Circuit Voltage Exceeding 500 mV Prepared via Close-Space Sublimation and Selenization

Ping Fan; Guo-Jie Chen; Shuo Chen; Zhuang-Hao Zheng; Muhammad Azam; Nafees Ahmad; Zheng-Hua Su; Guang-Xing Liang; Xiang-Hua Zhang; Zhi-Gang Chen

doi:10.1021/acsami.1c13223

Quasi-Vertically Oriented Sb₂Se₃ Thin-Film Solar Cells with Open-Circuit Voltage Exceeding 500 mV Prepared via Close-Space Sublimation and Selenization

ACS Appl Mater Interfaces. 2021 Oct 6;13(39):46671-46680. doi: 10.1021/acsami.1c13223. Epub 2021 Sep 27.

Authors

Affiliations

¹ Shenzhen Key Laboratory of Advanced Thin Films and Applications, Key Laboratory of Optoelectronic Devices and Systems, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, P. R. China.
² Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes) UMR 6226, Rennes F-35000, France.
³ Centre for Future Materials, University of Southern Queensland, Springfield Central, Queensland 4300, Australia.
⁴ School of Mechanical and Mining Engineering, The University of Queensland, St. Lucia, Queensland 4072, Australia.

PMID: 34569779
DOI: 10.1021/acsami.1c13223

Abstract

Sb₂Se₃, one of the most desirable absorption materials for next-generation thin-film solar cells, has an excellent photovoltaic characteristic. The [hk1]-oriented (quasi-vertically oriented) Sb₂Se₃ thin film is more beneficial for promoting efficient carrier transport than the [hk0]-oriented Sb₂Se₃ thin film. Controlling thin-film orientation remains the main obstacle to the further improvement in the efficiency of Sb₂Se₃-based solar cells. In this work, the controlled [hk0] or [hk1] orientation of the Sb₂Se₃ precursor is readily adjusted by tuning the substrate temperature and the distance between the source and the sample in close-space sublimation (CSS). Well-crystallized stoichiometric Sb₂Se₃ thin films with the desired orientation and large crystal grains are successfully prepared after selenization. Sb₂Se₃ thin-film solar cells in a substrate configuration of glass/Mo/Sb₂Se₃/CdS/ITO/Ag are fabricated with a power conversion efficiency of 4.86% with a record open-circuit voltage (V_OC) of 509 mV. The significant improvement in V_OC is closely related to the quasi-vertically oriented Sb₂Se₃ absorber layer with reduced deep-level defect density in the bulk and defect passivation at the Sb₂Se₃/CdS heterojunction. This work indicates that CSS and selenization show a remarkable potential for the fabrication of high-efficiency Sb₂Se₃ solar cells.

Keywords: Sb2Se3; close-space sublimation; open-circuit voltage; orientation; solar cell.