卤化物钙钛矿半导体透射电镜表征的挑战与机遇

Challenges and opportunities of transmission electron microscope characterizations of halide perovskites semiconductors

卤化物钙钛矿价格低廉,易于合成,具有优异的光电性能,广泛应用于太阳能电池、光电探测器和发光二极管等光电子器件,是当前国际上研究的热点领域,同时入选工信部和国资委评出的首批前沿材料之一。透射电子显微镜表征是揭示卤化物钙钛矿形貌、结构、成分等物理和化学信息的关键。然而,卤化物钙钛矿在电子束辐照下易分解,这种极端敏感性通常会阻碍我们获取钙钛矿本征信息,甚至引起假象。基于此,本文综述了近年来有关卤化物钙钛矿的透射电子显微学研究,重点讨论了卤化物钙钛矿电子束损伤机理、影响钙钛矿电子束敏感性因素、如何降低电子束损伤并获得钙钛矿原子尺度信息。本文旨在引起人们对卤化物钙钛矿电子束敏感性的关注,指导卤化物钙钛矿电子显微学表征,揭示卤化物钙钛矿分解机理,为构建高效稳定的钙钛矿光电器件提供实验指导。

Halide perovskites are widely applied in optoelectronic devices,including solar cells,photoelectric detectors,and light⁃emitting diodes,due to their low cost,facile synthesis,and excellent optoelectronic properties.This has made them a prominent area of international research.Halide perovskites are also recognized as cutting⁃edge materials by the ministry of industry and information technology and administration commission of the state council.Transmission electron microscope(TEM)characterizations are crucial for revealing physical and chemical information such as the morphology,structure and composition of halide perovskites.However,these materials are highly sensitive to electron beam irradiation,which can lead to decomposition.This sensitivity often hinders the acquisition of the intrinsic information and may even result in incorrect conclusion.This review examined recent TEM studies on halide perovskites,focusing on the mechanisms of electron beam damage,factors affecting electron beam sensitivity,and strategies to mitigate damage while obtaining atomic⁃scale structure information.The goal is to raise awareness about the electron beam sensitivity of halide perovskites,guide TEM characterizations,uncover the decomposition mechanisms,and provide theoretical insights for developing efficient and stable perovskite optoelectronic devices.