FA^(+)掺杂对无机钙钛矿CsPbBr_(3)发光性能的提升及其在白光发光二极管中的应用  

Optimization of Optical Properties of Inorganic Perovskite CsPbBr_(3)by FA^(+)Doping and Application in Light-emitting Diodes

作　　者：刘钰鑫 边昂 LIU Yuxin;BIAN Ang(School of Science,Jiangsu University of Science and Technology,Zhenjiang 212100,China)

机构地区：[1]江苏科技大学理学院,江苏镇江212100

出　　处：《发光学报》2024年第11期1860-1870,共11页Chinese Journal of Luminescence

基　　金：国家自然科学基金(62305135)。

摘　　要：钙钛矿半导体材料因其优异的光电转换特性、可调带隙、易于制备及低成本等优势,被广泛认为在新一代发光显示和光伏器件中具有巨大的应用潜力。CsPbBr_(3)等无机钙钛矿量子点凭借其独特的发光性质,已成为钙钛矿发光研究领域的焦点。然而,其发光性能和环境稳定性仍存在一定局限性。本文通过有机阳离子掺杂策略结合稳态和瞬态光谱学手段,系统研究了甲脒离子(FA^(+))掺杂对全无机钙钛矿CsPbBr_(3)光学性能和稳定性的优化。研究结果发现,FA+掺杂显著增强了CsPbBr_(3)发光性能,且在FA^(+)比例为20%时,其光致发光强度最强,较未掺杂前提高约2.8倍。结合变温荧光光谱分析,确定Cs_(0.8)FA_(0.2)PbBr_(3)的激子结合能为47.1 meV。FA^(+)的掺杂使得CsPbBr_(3)的纵向光学声子能降低,这有助于降低非辐射跃迁速率并提升发光量子产率。瞬态光谱分析表明,CsPbBr_(3)中掺杂FA+后,减缓了带内热激子弛豫和非辐射复合,从而使平均荧光寿命从13.68 ns增加至19.56 ns,激子寿命从774.1 ps延长至1319.2 ps。基于上述Cs_(0.8)FA_(0.2)PbBr_(3)量子点制备的发光二极管展现出发光稳定且理想的白光,其色度坐标为(0.3784,0.3163)。研究结果证实了掺杂甲脒离子来调控CsPbBr_(3)量子点光学性能的可行性,为白光发光二极管的设计和应用提供了指导。Perovskite semiconductor materials,due to their excellent luminescent properties,tunable band gaps,ease of fabrication,and low cost,are widely regarded as having great potential for application in next-generation light-emitting diodes and semiconductor display devices.Inorganic perovskite quantum dots,represented by CsPb⁃Br_(3),have attracted significant attention for their unique luminescent properties and have become a primary research focus.However,their luminescent performance and environmental stability still have certain limitations.This paper systematically studies the optimization of optical properties and stability of all-inorganic perovskite CsPbBr_(₃)through an organic cation doping strategy combined with steady-state and transient spectroscopic techniques.The research re⁃sults show that FA^(+)doping significantly enhances the luminescent performance of CsPbBr_(3),with the strongest photo⁃luminescence intensity observed when the FA+proportion is 20%.Through temperature-dependent photolumines⁃cence spectroscopy analysis,the exciton binding energy of Cs_(0.8)FA_(0.2)PbBr_(3)was determined to be 47.1 meV.FA^(+)doping reduces the longitudinal optical phonon energy of CsPbBr3,which helps lower the non-radiative transition rate and improves the photoluminescence quantum yield.Transient spectroscopy analysis indicates that,after the incorpo⁃ration of FA⁺into CsPbBr_(₃),the intraband hot exciton relaxation and non-radiative recombination are slowed down,resulting in an increase in the average photoluminescence lifetime from 13.68 ns to 19.56 ns,and an extension of ex⁃citon lifetime from 774.1 ps to 1319.2 ps.LEDs based on the synthesized Cs_(0.8)FA(0.2)PbBr_(3)quantum dots exhibit sta⁃ble emission and ideal white light,with chromaticity coordinates of(0.3784,0.3163).The research results confirm the feasibility of doping FA^(⁺)in regulating the optical properties of CsPbBr_(₃)quantum dots and provide valuable guid⁃ance for the design and application of white light-emitting diodes.

关 键 词：有机-无机杂化钙钛矿 甲脒离子掺杂 荧光光谱 瞬态光谱 白光LED 

分 类 号：O482.31[理学—固体物理]