Abstract Halide perovskite single-crystal films have attracted significant attention due to their extraordinary performance in various optoelectronic applications such as solar cells, light-emitting devices, photodetectors, and X-ray detectors. However, the surface quality and crystallinity of perovskite single crystal films (PSCFs) prepared by the popular space-confined method limits the applications in the high-performance devices. Herein, we demonstrate a simple method to improve the crystallinity of MAPbBr3 PSCFs by introducing dimethylsulfoxide (DMSO) as the coordination solvent into the precursor solutions. When increasing the DMSO concentration in the perovskite precursor solutions, the precipitation of lead bromide on the surface of PSCFs is suppressed. The best MAPbBr3 PSCF obtained at 2.5% DMSO concentration has a full width at half maximum (FWHM) of 0.0042° in the X-ray rocking curve measurements, which is significantly improved compared with the best published results. The mechanism how DMSO concentration affect the crystallization process and the formation of defects is also discussed. The study provides an effective route to fabricate perovskite single crystal films and inspires further explorations on the production of high-performance optoelectronic devices.

中文翻译：

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DMSO浓度在MAPbBr3钙钛矿单晶薄膜结晶过程中的作用

摘要 卤化物钙钛矿单晶薄膜因其在太阳能电池、发光器件、光电探测器和 X 射线探测器等各种光电应用中的卓越性能而备受关注。然而，由流行的空间受限方法制备的钙钛矿单晶薄膜（PSCFs）的表面质量和结晶度限制了其在高性能器件中的应用。在此，我们展示了一种通过将二甲基亚砜 (DMSO) 作为配位溶剂引入前体溶液来提高 MAPbBr3 PSCFs 结晶度的简单方法。当增加钙钛矿前驱体溶液中 DMSO 的浓度时，溴化铅在 PSCF 表面的沉淀受到抑制。在 2 时获得的最佳 MAPbBr3 PSCF。5% DMSO 浓度在 X 射线摇摆曲线测量中的半峰全宽 (FWHM) 为 0.0042°，与已发表的最佳结果相比有显着改善。还讨论了 DMSO 浓度如何影响结晶过程和缺陷形成的机制。该研究为制备钙钛矿单晶薄膜提供了一条有效途径，并激发了对高性能光电器件生产的进一步探索。