Carrier Transport Enhancement Mechanism in Highly Efficient Antimony Selenide Thin‐Film Solar Cell

• DOI: 10.1002/adfm.202213941
• Publication Date: 2023-01-16T04:40:48Z
• Authors: Yandi Luo; Guojie Chen; Shuo Chen; Nafees Ahmad; Muhammad Azam; Zhuanghao Zheng; Zhenghua Su; Michel Cathelinaud; Hongli Ma; Zhigang Chen; Ping Fan; Xianghua Zhang; Guangxing Liang
• Keywords: Sb Se solar cells; band alignments; carrier transports; [CHIM]Chemical Sciences; 02 engineering and technology; 540; heterojunction interface engineering; 0210 nano-technology; 7. Clean energy; Sb2Se3 solar cells

AbstractExhibiting outstanding optoelectronic properties, antimony selenide (Sb2Se3) has attracted considerable interest and has been developed as a light absorber layer for thin‐film solar cells over the decade. However, current state‐of‐the‐art Sb2Se3 devices suffer from unsatisfactory “cliff‐like” band alignment and severe interface recombination loss, which deteriorates device performance. In this study, the heterojunction interface of an Sb2Se3 solar cell is improved by introducing effective aluminum (Al3+) cation into the CdS buffer layer. Then, the energy band alignment of Sb2Se3/CdS:Al heterojunction is modified from a “cliff‐like” structure to a “spike‐like” structure. Finally, heterojunction interface engineering suppresses recombination losses and strengthens carrier transport, resulting in a high efficiency of 8.41% for the substrate‐structured Sb2Se3 solar cell. This study proposes a facile strategy for interfacial treatment and elucidates the related carrier transport enhancement mechanism, paving a bright avenue to overcome the efficiency bottleneck of Sb2Se3 thin‐film solar cells.