基于离子化合物的高性能钙钛矿发光二极管  

Ionic-compound based high performance perovskite light emitting diodes

作　　者：黄鑫梅 何晓莉 徐强 陈平[1] 张勇[1] 高春红[1] Huang Xin-Mei;He Xiao-Li;Xu Qiang;Chen Ping;Zhang Yong;Gao Chun-Hong(School of Physical Science and Technology,Southwest University,Chongqing 400715,China)

机构地区：[1]西南大学物理科学与技术学院,重庆400715

出　　处：《物理学报》2022年第20期333-340,共8页Acta Physica Sinica

基　　金：国家留学基金资助出国西部地区人才培养特别项目(批准号:留金项[2018]10006号);中央高校基本科研业务费(批准号:XDJK2018C082)资助的课题。

摘　　要：金属卤化物钙钛矿因其颜色可调、颜色纯度高、光电性能好而备受关注,因而广泛应用于显示、照明等领域.近年来,对于钙钛矿发光二极管(perovskite light emitting doides,PeLEDs)的研究也越来越热门,要获得高性能PeLEDs,其发光层-钙钛矿薄膜的质量是关键因素之一.本工作采用离子化合物四苯基氯化膦(tetraphenylphosphinium chloride,TPPCl)作准二维钙钛矿薄膜的添加剂,制作了具有双电子传输层的高性能准二维PeLEDs.其最佳器件的最大亮度(25285 cd/m^(2))、最大电流效率(65.9 cd/A)和最大外量子效率(17.3%)分别是控制器件的4.1,7.2和7.2倍.通过对其光电性能提高的物理机理进行研究,发现TPPCl的引入不仅可以提高钙钛矿薄膜的质量,减少缺陷,还可以调节结晶相的分布,从而更好地将激子限制在发光层中,最终在能量漏斗效应的辅助下获得更好的光致发光和电致发光性能.Metal halide perovskite has attracted much attention due to its adjustable color,high color purity,and excellent photoelectric properties.The quality of the perovskite film is one of the key factors that affect the performance of device.Here,PEACsPbBrthin films are prepared by directly doping the ionic compound additive tetraphenylphosphine chloride(TPPC1)into the perovskite precursor of the light-emitting layer based on additive assisted technology.High-quality perovskite films with uniform,less pinholes and smaller grains are obtained.Not only is the photoluminescence(PL)performance of PeLEDs improved but the electroluminescence(EL)performance of PeLEDs with a double electron transport layer also turns better.The maximum brightness is 25285 cd/m^(2).The maximum current efficiency is 65.9 cd/A.And the maximum EQE is 17.3%.The method of adding ionic compounds to the perovskite precursor can not only improve the carrier transport behavior,but also make the formed small n crystal phases and large n crystal phase more balance,leading to the energy funnel effect to be enhanced.Further investigation by FTIR proves that the TPPC1 can passivate the perovskite film,and thus greatly improving the EQE value of the PeLED.This researchpresents a simple and efficient method of developing high-performance quasi-two-dimensional green PeLEDs.

关 键 词：钙钛矿发光二极管 四苯基氯化膦 光致发光 电致发光 

分 类 号：TN312.8[电子电信—物理电子学] TB383.2[一般工业技术—材料科学与工程]