表面修饰提升CsPbBr_(3)钙钛矿纳米晶的稳定性  

Surface modification strategy improves stability of CsPbBr_(3) perovskite nanocrystals

作　　者：徐天成 李金凯[1] 刘宗明[1] XU Tiancheng;LI Jinkai;LIU Zongming(School of Material Science and Engineering,University of Jinan,Jinan 250022,China)

机构地区：[1]济南大学材料科学与工程学院,山东济南250022

出　　处：《中国粉体技术》2024年第5期1-8,共8页China Powder Science and Technology

基　　金：国家自然科学基金项目,编号:51402125;山东省自然科学基金项目,编号:ZR2020ME045、ZR2020ME046;济南市“新高校20条”项目,编号:2021GXRCO99、T202204。

摘　　要：【目的】分析不同配体添加量对CsPbBr_(3)钙钛矿纳米晶表面修饰后的光学性能影响,实现纳米晶稳定性和光学性能提升。【方法】通过水相合成方法合成CsPbBr_(3)钙钛矿纳米晶,制备过程原位引入短碳链的L-天冬氨酸(L-aspartate,L-Asp)和油胺(oleylamine,OAm)配体对纳米晶的表面进行修饰,并研究Cs4PbBr6向CsPbBr_(3)的晶相转变机制。【结果】L-Asp和OAm配体均匀吸附于纳米晶表面,使纳米晶在水中具有优异的分散性,且结晶性良好;CsPbBr_(3)钙钛矿纳米晶的最大发射波长为517 nm处,半峰宽为17 nm,分散在水中11 h后依旧能够具有绿色发射且发射峰位没有明显移动。【结论】经L-Asp和OAm配体修饰的CsPbBr_(3)钙钛矿纳米晶在保持优异光学性能的同时还具有良好的溶液稳定性。Objective In recent years,all-inorganic lead halide perovskite(CsPbX_(3),X=Cl,Br,I)nanocrystals,a type of nanoscale composite material,have attracted significant attention from materials scientists.With a high photoluminescent quantum yield,an extremely narrow full width at half maximum(FWHM),tunable emission across the visible spectrum,and high carrier mobility,CsPbX_(3) is rapidly becoming one of the most promising materials for optoelectronic devices.However,due to their unique properties,perovskite materials exhibit low stability in aqueous solutions and typically need to be synthesized in non-polar organic solvents to prevent decomposition.To enhance stability,it is necessary to modify their surface with hydrophobic groups,which greatly restricts their application in aqueous environments.To overcome these challenges,researchers are exploring green,simple,aqueous-phase synthesis methods to directly synthesize perovskite nanocrystals with specific functions.Traditional synthesis methods typically avoid water to prevent adverse effects on the structure and properties of the highly water-sensitive perovskite nanocrystals.Nonetheless,recent research has shown that the presence of water is not always a disadvantage.In this study,the stability and optical properties of CsPbBr_(3)perovskite nanocrystals were improved by introducing L-aspartate ligands instead of OA ligands.Methods The entire synthesis process was conducted in air without inert gas protection,as shown in Fig.1.CsBr(0.4 mmol)and PbBr2(0.4 mmol)were dissolved in 10 mL of N,N-dimethylacetamide(DMA)solution,heated to 50 oC,and magnetically stirred for 45 min until completely dissolved.Subsequently,800μL of OAm was added,during which the solution gradually changed from colorless to white turbid.The precursor was recorded as Cs4PbBr6 NCs.After 15 min of continued stirring,1 mL of the white precursor solution was added into deionized water containing L-aspartate.After 10 s of reaction,the resulting mixture was centrifuged for subsequent characterization.Th

关 键 词：钙钛矿 纳米晶 表面修饰 光学性能 L-天冬氨酸 油胺 

分 类 号：TN384[电子电信—物理电子学] TB4[一般工业技术]