Timasi N, Tafazoli S, Nouri E, Mohammadi M R, Li Y
Department of Materials Science and Engineering, Sharif University of Technology, Azadi Ave., Tehran, Iran.
Photochem Photobiol Sci. 2019 May 15;18(5):1228-1234. doi: 10.1039/c9pp00071b.
Solvent engineering as a crucial factor in determining the photovoltaic performance of perovskite solar cells has attracted much attention in recent years. Herein, we treat PbI2 and perovskite films with isopropyl alcohol, acetone, diethyl ether and dichloromethane, as standard solvents, in a modified two-step method. Meanwhile, triethylenetetramine (TETA) is introduced as a new reagent in solvent engineering for perovskite solar cell devices. Structural, optical and photovoltaic characteristics of the TETA-treated perovskite films are compared with those of the ones treated with different solvents. A shiny, pinhole-free and full-coverage texture with sufficiently large grain sizes is obtained in the presence of TETA, suggesting an efficient solvent engineering for perovskite layers. Moreover, the results reveal that residual PbI2 is completely removed and converted to a crystalline perovskite film. Amongst the PSC devices engineered with various solvents, the TETA-treated film exhibits a 55% increase in photoconversion efficiency compared to the control device with no solvent engineering.
溶剂工程作为决定钙钛矿太阳能电池光伏性能的关键因素，近年来备受关注。在此，我们采用改良的两步法，用异丙醇、丙酮、二乙醚和二氯甲烷等标准溶剂处理PbI₂和钙钛矿薄膜。同时，引入三亚乙基四胺（TETA）作为钙钛矿太阳能电池器件溶剂工程中的一种新试剂。将经TETA处理的钙钛矿薄膜的结构、光学和光伏特性与用不同溶剂处理的薄膜进行比较。在TETA存在的情况下，获得了具有足够大晶粒尺寸的光亮、无针孔且全覆盖的织构，这表明对钙钛矿层进行了有效的溶剂工程处理。此外，结果表明残留的PbI₂被完全去除并转化为结晶钙钛矿薄膜。在用各种溶剂设计的PSC器件中，与未进行溶剂工程处理的对照器件相比，经TETA处理的薄膜的光转换效率提高了55%。
