Synthesis of CsPbX_(3)(X=Cl/Br,Br,and Br/I)@SiO_(2)/PM M A composite films as color-conversion materials for achieving tunable multi-color and white light emission

作     者：Varnakavi Naresh Byung Hyo Kim Nohyun Lee Varnakavi Naresh;Byung Hyo Kim;Nohyun Lee

作者机构：School of Advanced Materials EngineeringKookmin UniversitySeoul 02707Republic of Korea Department of Organic Materials and Fiber EngineeringSoongsil UniversitySeoul 06978Republic of Korea 

出 版 物：《Nano Research》 (纳米研究（英文版）)

年 卷 期：2021年第14卷第4期

页      面：1187-1194页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：the Space Core Technology Development Program(No.2017M1A3A3A02016782) 

主　　题：lead halide perovskite nanocrystals hot-injection method long term stability PL quantum yield SiO_(2)/PMMA encapsulation white peLED performance 

摘      要：All-inorganic cesium lead halide based perovskite nanocrystals(PNCs)exhibit promising optoelectronic properties,but their poor stability and anion exchange reaction limit their broad commercial ***,we demonstrated the successful synthesis of blue-green-red emitting CsPbX_(3)(X=Cl/Br,Br,and Br/I)PNCs via hot injection method,followed by silica-coating and embedding in poly(methylmethacrylate)(PMMA)*** photoluminescence(PL)spectra of SiO_(2)/PMMA-coated PNCs can be tuned continuously by regulating precursor composition ratio,from blue(CsPb(Cl_(0.5)/Br_(0.5))_(3);460 nm)to red(CsPb(Br_(0.4)/I_(0.6))_(3)via green(CsPbBr_(3);519 nm).The PNCs composite films exhibit improved stability(thermal-,moisture-,and photo-stability)because of the barrier formed by Si0_(2)/PMMA coating and also displayed exceptional photoluminescent quantum yield(PLQY of blue,green,and red-emitting Si0_(2)/PMMA coated PNCs are 37%,86%,and 71%,respectively)with longer lifetimes inhibiting anion ***,the PNCs-encapsulated Si0_(2)/PMMA composite films were integrated into the UV LED chip as down-converting materials to construct a prototype white-peLED *** designed white-peLED unit demonstrated bright white light generating CIE coordinates(0.349,0.350),a luminous efficiency(LE)of 39.2%and a color rendering index(CRI)of *** wide color gamut of 121.47%of NTSC and 98.56%of Rec.2020 is also achieved with the built w-LED ***,the results demonstrated that CsPbX_(3)(X=Cl/Br,Br,and Br/I)PNCs@SiO_(2)/PMMA composite films can be employed as efficient UV to visible color conversion materials for white-LEDs and backlighting.