CdBr_(2)后处理制备带隙可调的Mn∶CsPbX_(3)钙钛矿纳米晶及其发光性质  

Preparation and Luminescent Properties of Mn∶CsPbX_(3)Perovskite Nanocrystals with Tunable Bandgap by CdBr_(2)Post-Treatme

作　　者：季思航 赵丽佳 刘梓璇 赵柯 冯晟铭 王鹤燃 曹希悦 袁曦 Ji Sihang;Zhao Lijia;Liu Zixuan;Zhao Ke;Feng Shengming;Wang Heran;Cao Xiyue;Yuan Xi(Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education,College of Information Technology,Jilin Normal University,Siping 136000,China)

机构地区：[1]吉林师范大学信息技术学院功能材料物理与化学教育部重点实验室,吉林四平136000

出　　处：《微纳电子技术》2024年第9期39-46,共8页Micronanoelectronic Technology

基　　金：吉林省科技发展计划项目(YDZJ202301ZYTS389,20210101161JC)。

摘　　要：铅卤钙钛矿(APbX_(3),A=Cs、MA、FA,X=Cl、Br、I)纳米晶(NC)因其卓越的光电性质受到广泛关注,但Mn的4T1-6A1能级与带边能级不易匹配,制备高质量Mn掺杂钙钛矿晶体仍然存在困难。通过CdBr_(2)后处理技术,在室温下获得了光学带隙可调的Mn∶CsPbX_(3)(X=Cl、Br)纳米晶。通过B位金属和阴离子共掺杂法,实现稳定高效的Mn红光发射。将痕量CdBr_(2)后处理液逐滴加入Mn∶CsPbCl_(3)纳米晶原液中,可以将带边激子发光波长从405 nm调控到475 nm,Mn发光寿命呈单指数衰减,获得的纳米晶量子产率最高达97%。卤素离子交换影响了Mn周围晶体场环境,导致Mn发光寿命变短。通过透射电子显微镜(TEM)和X射线衍射仪(XRD)进行形貌结构分析,发现CdBr_(2)处理前后钙钛矿纳米晶立方形状没有明显变化,XRD衍射峰位保持不变,表明成功实现了金属离子和卤素离子的共交换。此外,通过变温动力学研究发现,这种发光增强源于Cd离子掺杂减少了纳米晶的非辐射缺陷态,增强了激子到Mn的能量传递。这种后处理的B位阳离子掺杂技术可能成为提高钙钛矿晶体量子产率的普适方法。Lead halide perovskite(APbX_(3),A=Cs,MA,FA;X=Cl,Br,I)nanocrystals(NCs)have attracted widespread attention due to their excellent optoelectronic properties.The Mn 4T1-6A1 energy level is not easily matched with the band edge,making it difficult to prepare high-quality Mn doped perovskite crystals.By using CdBr_(2)post-treatment processing,Mn∶CsPbX_(3)(X=Cl,Br)nanocrystals with adjustable optical bandgap were obtained at room temperature.Stable and efficient red light emission was achieved through co-doping of B-site metals and anions.By adding trace amounts of CdBr_(2)post-treatment solution dropwise to the original solution of Mn∶CsPbCl_(3)nanocrystals,the band-edge exciton wavelength can be adjusted from 405 nm to 475 nm,and the luminescence lifetime of Mn exhibits a single-exponential decay,and up to 97%of the nanocrystalline quantum yield was obtained.Halogen ion exchange affects the crystal field environment around Mn,resulting in a shorter luminescence lifetime of Mn.Morphology structures were analyzed through transmission electron microscope(TEM)and X-ray diffractometer(XRD),it was found that there was no significant change in the cubic shape of perovskite nanocrystals before and after CdBr_(2)treatment,while the XRD diffraction peak remained unchanged,indicating that co-exchange of metal ions and halogen ions was successfully achieved.In addition,through temperature-dependent kinetics research,it is found that the luminescence enhancement is due to the reduction of nonradiative defect states in NCs by Cd ion doping,which enhances energy transfer from excitons to Mn.The post-processing B-site cation doping technique may be a universal method for improving the quantum yield of perovskite crystals.

关 键 词：MN掺杂 铅卤钙钛矿 纳米晶 量子产率:CdBr_(2)后处理 

分 类 号：TN383[电子电信—物理电子学]