基于准二维钙钛矿的窄线宽红光电致发光器件性能研究

Performance of Narrow-linewidth Red Emitted Electroluminescent Devices Based on Quasi-two-dimensional Perovskite

金属卤化物钙钛矿发光二极管(PeLEDs)具有宽色域和高色纯度,在照明和显示方面有着广阔的应用前景。英国伦敦大学研究团队发表于Scientific Reports的一项开创性研究发现,每天只需暴露在红光下3 min,就能显著缓解视力下降。而钙钛矿的光谱可调性及较高的色纯度都为护眼红光PeLEDs的实现提供了保障。与以往的界面工程、配体工程等不同,本文从结构优化的角度来提升准二维钙钛矿红光PeLEDs的外量子效率(EQE),即结合微腔结构实现线宽更窄的红光电致发光器件。结果表明,将分布式布拉格反射镜(DBR)与PeLEDs相结合,设计并制备的基于微腔结构的高性能PeLEDs在窄化PeLED的电致发光(EL)半高全宽的基础上实现了EQE成倍增长,最大EQE能达到11.26%。相较于同条件下制备的参比器件,具有微腔结构的PeLED器件EL线宽窄化到参比器件的1/3,仅为11 nm。

Metal halide perovskite light-emitting diodes(PeLEDs)have wide color gamut and high color purity,with broad application prospects in lighting and displays.A groundbreaking study by a research team at the University of London published in Scientific Reports found that exposure to red light for just 3 minutes a day could significantly alleviate vision decline.The tunability of perovskite’s spectrum and its high color purity provide assurance for the realization of eye-protective red-emitted PeLEDs.Unlike previous interface engineering or ligand engineering methods,this paper proposes a new approach to enhance the external quantum efficiency(EQE)of quasi-two-dimensional perovskite red PeLEDs by combining them with microcavity structures to achieve narrower linewidths in electroluminescent devices.The results show that by integrating distributed Bragg reflectors(DBRs)with PeLEDs,narrow linewidth high-performance PeLEDs based on microcavity structures were designed and fabricated,achieving a doubling of EQE on top of narrowing the electroluminescence(EL)full width at half maximum for microcavity PeLEDs,with a maximum EQE reaching 11.26%.Compared to reference devices prepared under the same conditions,PeLED devices with microcavity structures narrowed their EL linewidth to one-third that of reference devices,only 11 nm.