Highly stable metal halides Cs_(2)ZnX_(4)(X = Cl, Br) with Sn2+ as dopants for efficient deep-red photoluminescence  

作　　者：Yan Zhang Lei Zhou Lei Zhang Wei Luo Wei Shen Ming Li Rongxing He 

机构地区：[1]Key Laboratory of Luminescence Analysis and Molecular Sensing(Southwest University),Ministry of Education,College of Chemistry and Chemical Engineering,Southwest University,Chongqing 400715,China

出　　处：《Chinese Chemical Letters》2023年第2期362-366,共5页中国化学快报（英文版）

基　　金：the financial supports from National Natural Science Foundation of China (Nos. 91741105, 22109130);Chongqing Municipal Natural Science Foundation (Nos. cstc2018jcyj AX0625, cstc2021jcyj-msxm X1180);Program for Innovation Team Building at Institutions of Higher Education in Chongqing (No. CXTDX201601011)。

摘　　要：The development of deep-red emitting lead-free metal-halide perovskites with high photoluminescence quantum yields (PLQYs) and outstanding stability remains a major challenge for displays and deep-tissue bioimaging.In this work,we report a facile and convenient solvothermal method to synthesize metal halides Cs_(2)Zn X_(4)(X=Cl,Br) that however is PL innert at room temperature.Upon composition engineering utilizing Sn^(2+) as the dopant,the resulting Cs_(2)Zn Cl_(4):Sn not only emits strong deep-red PL peaked at700 nm with the highest 99.4%PLQY among the similar materials so far,but also exhibits excellent structure stability in air (PLQY remains 96%after one year exposure to the atmosphere).Detailed experimental characterizations and theoretical calculations reveal that the deep-red emission stems from self-trapped excitons induced by the Sn^(2+) dopant.Particularly,triplet emission (^(3)P_(2)→^(1)S_(0)) from Sn-5s^(2) orbitals has been observed at low temperature due to the break of parity-forbidden transition.This work provides an important guidance for the development of deep-red light-emitting materials with low price,high efficiency and excellent stability.

关 键 词：Lead-free metal halides Deep-red emission PHOTOLUMINESCENCE High efficiency Stability 

分 类 号：TB34[一般工业技术—材料科学与工程]