Xiao Bo, Li Xin, Yi Zijun, Luo Yubo, Jiang Qinghui, Yang Junyou
State Key Laboratory of Material Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China.
Solar Energy Research Institute of Singapore, National University of Singapore, Singapore 117574, Singapore.
ACS Appl Mater Interfaces. 2022 Feb 16;14(6):7962-7971. doi: 10.1021/acsami.1c22452. Epub 2022 Feb 4.
Tin oxide (SnO) has been commonly used as an electron transport layer (ETL) in planar perovskite solar cells (p-PSCs) because it can be prepared by a low-temperature solution-processed method. However, the device performance has been restricted due to the limited electrical performance of SnO and its mismatched energy level alignment with the perovskite absorber. Considering these problems, sodium tungstate (NaWO) has been employed to modify the SnO ETL. The conduction band minimum of SnO increases and the defects at the ETL/perovskite interface decrease by the modification of the SnO ETL with NaWO, thus reducing the energy barrier between the ETL and perovskite. In addition, the electron extraction ability has been enhanced and the interface recombination between the ETL and perovskite has also been inhibited. As a result, the photovoltaic performance of p-PSCs based on the modified ETL has been improved, and a champion power conversion efficiency of 21.16% has been achieved compared with the control device of 17.30% with an open circuit voltage increased from 1.075 to 1.162 V.
氧化锡（SnO）通常用作平面钙钛矿太阳能电池（p-PSC）中的电子传输层（ETL），因为它可以通过低温溶液处理方法制备。然而，由于SnO的有限电性能及其与钙钛矿吸收层不匹配的能级对准，器件性能受到限制。考虑到这些问题，钨酸钠（NaWO）已被用于修饰SnO电子传输层。通过用NaWO修饰SnO电子传输层，SnO的导带最小值增加，电子传输层/钙钛矿界面处的缺陷减少，从而降低了电子传输层和钙钛矿之间的能垒。此外，电子提取能力得到增强，电子传输层和钙钛矿之间的界面复合也受到抑制。结果，基于修饰后的电子传输层的p-PSC的光伏性能得到改善，与开路电压从1.075 V增加到1.162 V的17.30%的对照器件相比，获得了21.16%的最佳功率转换效率。
