Saraf Rohit, Mathur Avi, Maheshwari Vivek
Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
ACS Appl Mater Interfaces. 2020 Jun 3;12(22):25011-25019. doi: 10.1021/acsami.0c04346. Epub 2020 May 21.
A commodity-scale polymer is used for controlling the nucleation and growth of single crystals of organolead halide perovskite. The polymer [polystyrene (PS)] cross-links and strongly interacts with PbI and MAI (MAPbI perovskite precursors) resulting in the control of the crystallization process. The PS concentration modulates the nucleation time, crystal size, and the number of perovskite single crystals. In addition, the PS-based MAPbI crystals show an enhanced performance as well as improved thermal and environmental stability. Specifically, the PS-MAPbI crystals show 3 times higher photocurrent than plain MAPbI crystals and maintain a stable structure for more than 50 days (1200 h) under continuous 0.1 sun illumination in the air with a relative humidity of 40-45%. The improved performance and stability are attributed to the direct interaction between the PS and perovskite, which greatly reduces the ion migration, defect traps, and charge recombination and improves the carrier mobility and lifetime.
一种商品规模的聚合物用于控制有机铅卤化物钙钛矿单晶的成核和生长。该聚合物[聚苯乙烯（PS）]交联并与PbI和MAI（MAPbI钙钛矿前驱体）强烈相互作用，从而控制结晶过程。PS浓度调节成核时间、晶体尺寸和钙钛矿单晶的数量。此外，基于PS的MAPbI晶体表现出增强的性能以及改善的热稳定性和环境稳定性。具体而言，PS-MAPbI晶体的光电流比普通MAPbI晶体高3倍，并且在相对湿度为40-45%的空气中连续0.1太阳光照下，能保持稳定结构超过50天（1200小时）。性能和稳定性的提高归因于PS与钙钛矿之间的直接相互作用，这大大减少了离子迁移、缺陷陷阱和电荷复合，并提高了载流子迁移率和寿命。
