Li Shunran, Luo Jiajun, Liu Jing, Tang Jiang
Sargent Joint Research Center, Wuhan National Laboratory for Optoelectronics (WNLO) and School of Optical and Electronic Information , Huazhong University of Science and Technology (HUST) , Wuhan 430074 , China.
J Phys Chem Lett. 2019 Apr 18;10(8):1999-2007. doi: 10.1021/acs.jpclett.8b03604. Epub 2019 Apr 10.
Photoluminescence is a radiative recombination process of electron-hole pairs. Self-trapped excitons (STEs), occurring in a material with soft lattice and strong electron-phonon coupling, emit photons with broad spectrum and large Stokes shift. Recently, series halide perovskites with efficient STE emission have been reported and showed promise for solid-state lighting. In this Perspective, we present an overview of various photoluminescence phenomena with the emphasis on the mechanism and characteristics of emission derived from STEs. This is followed by the introduction of STE emission in hybrid halide perovskites. We then introduce all-inorganic STE emitters and focus in particular on the mechanism of STEs in double-perovskite CsAgInCl and strategies for efficiency improvement. Finally, we summarize the current photoluminescence and electroluminescence applications of STE emitters as well as the potential in luminescent solar concentrators and provide an overview of future research opportunities.
光致发光是电子 - 空穴对的辐射复合过程。自陷激子（STE）出现在晶格柔软且电子 - 声子耦合强的材料中，发射具有宽光谱和大斯托克斯位移的光子。最近，已报道了具有高效STE发射的系列卤化物钙钛矿，并显示出在固态照明方面的潜力。在这篇综述中，我们概述了各种光致发光现象，重点是源自STE的发射机制和特性。接下来介绍混合卤化物钙钛矿中的STE发射。然后我们引入全无机STE发射体，并特别关注双钙钛矿CsAgInCl中STE的机制以及效率提高策略。最后，我们总结了STE发射体当前的光致发光和电致发光应用以及在发光太阳能聚光器中的潜力，并概述了未来的研究机会。
