Chen Shangshang, Xiao Xun, Gu Hangyu, Huang Jinsong
Department of Applied Physical Sciences, University of North Carolina, Chapel Hill, NC 27599, USA.
Sci Adv. 2021 Mar 3;7(10). doi: 10.1126/sciadv.abe8130. Print 2021 Mar.
Perovskite-based electronic materials and devices such as perovskite solar cells (PSCs) have notoriously bad reproducibility, which greatly impedes both fundamental understanding of their intrinsic properties and real-world applications. Here, we report that organic iodide perovskite precursors can be oxidized to I even for carefully sealed precursor powders or solutions, which markedly deteriorates the performance and reproducibility of PSCs. Adding benzylhydrazine hydrochloride (BHC) as a reductant into degraded precursor solutions can effectively reduce the detrimental I back to I, accompanied by a substantial reduction of I -induced charge traps in the films. BHC residuals in perovskite films further stabilize the PSCs under operation conditions. BHC improves the stabilized efficiency of the blade-coated p-i-n structure PSCs to a record value of 23.2% (22.62 ± 0.40% certified by National Renewable Energy Laboratory), and the high-efficiency devices have a very high yield. A stabilized aperture efficiency of 18.2% is also achieved on a 35.8-cm mini-module.
基于钙钛矿的电子材料和器件，如钙钛矿太阳能电池（PSC），其可重复性极差，这极大地阻碍了对其固有特性的深入理解以及实际应用。在此，我们报告称，即使对于精心密封的前驱体粉末或溶液，有机碘化物钙钛矿前驱体也会被氧化为碘，这显著降低了PSC的性能和可重复性。在降解的前驱体溶液中添加苄基肼盐酸盐（BHC）作为还原剂，可以有效地将有害的碘还原为碘离子，同时大幅减少薄膜中碘诱导的电荷陷阱。钙钛矿薄膜中的BHC残留进一步稳定了PSC在工作条件下的性能。BHC将刮刀涂布的p-i-n结构PSC的稳定效率提高到创纪录的23.2%（经美国国家可再生能源实验室认证为22.62±0.40%），并且高效器件的良品率非常高。在一个35.8平方厘米的微型模块上也实现了18.2%的稳定孔径效率。
