Fabricating High‐Efficiency Sb<sub>2</sub>(S,Se)<sub>3</sub> Solar Cells by Novel Additive‐Assisted Longitudinal Component Engineering
Qiqiang Zhu, Weihuang Wang, Weihuang Wang, Zhi‐Rong Chen, Zixiu Cao, Weiyu Wang, Weiyu Wang, Xinxin Feng, Hui Deng, Caixia Zhang, Qiao Zheng, Jionghua Wu, Yi Zhang, Shuying Cheng
Abstract
Abstract Antimony selenosulfide (Sb 2 (S,Se) 3 ) solar cells have achieved an efficiency of over 10.0%. However, the uncontrollable hydrothermal process makes preparing high‐quality Sb 2 (S,Se) 3 thin films a bottleneck for efficient Sb 2 (S,Se) 3 solar cell. To address this problem, triethanolamine (TEA) additive is innovatively utilized to regulate the reaction kinetic process of Sb 2 (S,Se) 3 thin films in this work. The results show that TEA chelator can realize the time‐domain control of the reaction process, optimizing the Se/(S+Se) elemental distribution of Sb 2 (S,Se) 3 thin film and shrinking the bandgap offset of Sb 2 (S,Se) 3 thin film. Meanwhile, the (021) and (061) crystal orientation of Sb 2 (S,Se) 3 thin film are enhanced and the harmful V Se1 defects in Sb 2 (S,Se) 3 solar cells are passivated. Interestingly, a uniform back surface gradient for Sb 2 (S,Se) 3 thin film is formed to reduce the minority carrier recombination at the back contact, increase the photocurrent and decrease the diode current of Sb 2 (S,Se) 3 solar cells. Finally, the J sc and FF of Sb 2 (S,Se) 3 solar cells are significantly improved by 8.6% and 5.5% respectively, and the open‐circuit voltage deficit of the device is reduced by 44 mV, which leads to an efficiency of 9.94% which is the highest values of Sb 2 (S,Se) 3 solar cells by sodium selenosulfate system.