High-quality quantum dots(QDs)possess superior electroluminescent efficiencies and ultra-narrow emission linewidths are essential for realizing ultra-high definition QD light-emitting diodes(QLEDs).However,the synthes...High-quality quantum dots(QDs)possess superior electroluminescent efficiencies and ultra-narrow emission linewidths are essential for realizing ultra-high definition QD light-emitting diodes(QLEDs).However,the synthesis of such QDs remains challenging.In this study,we present a facile high-temperature successive ion layer adsorption and reaction(HT-SILAR)strategy for the growth of precisely tailored Zn_(1-x)Cd_(x)Se/ZnSe shells,and the consequent production of high-quality,large-particle,alloyed red CdZnSe/Zn_(1-x)Cd_(x)Se/ZnSe/ZnS/CdZnS QDs.The transitional Zn1 xCdxSe/ZnSe shells serve to effectively suppress heavy hole energy level splitting and weaken the exciton-longitudinal optical phonon coupling of QDs,thus facilitating the formation of highly luminescent QDs with a near-unity photoluminescence quantum yield of 97.8%and narrow emission with a full width at half maximum of 17.1 nm.In addition,the introduction of transitional shells can extend the particle size of QDs to 19.0 nm,which is beneficial for efficient carrier recombination and reduced Joule heating in QD-based LEDs.As a result,the fabricated QLEDs can achieve a record external quantum efficiency of 38.2%,luminance over 120,000 cd m^(-2),and exceptional operational stability T95(tested at 1,000 cd m^(-2))of 24,100 h.These findings provide new ave-nues for synthesizing high-quality QDs with high color purity.展开更多
基金financial support from the Science and Technology Development Fund,Macao SAR(0006/2021/AKP,0068/2022/A,0034/2022/AGJ)Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices(ZZ2102)+6 种基金Gusu Innovation and Entrepreneur Leading Talents(ZXL2023185)the Natural Science Foundation of Fujian Province(2021J02001)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Project Program(2021ZZ201)Guangdong-Macao Science and Technology Project(2023A0505020010)supported by Suzhou Key Laboratory of Functional Nano&Soft Materials,the Collaborative Innovation Center of Suzhou Nano Science and Technology(NANO-CIC)the 111 Project,Joint International Research Laboratory of Carbon-Based FunctionalMaterials and DevicesShuangQiao Sun acknowledges the support from Macao Young Scholars Program(MYSP,AM2024010).
文摘High-quality quantum dots(QDs)possess superior electroluminescent efficiencies and ultra-narrow emission linewidths are essential for realizing ultra-high definition QD light-emitting diodes(QLEDs).However,the synthesis of such QDs remains challenging.In this study,we present a facile high-temperature successive ion layer adsorption and reaction(HT-SILAR)strategy for the growth of precisely tailored Zn_(1-x)Cd_(x)Se/ZnSe shells,and the consequent production of high-quality,large-particle,alloyed red CdZnSe/Zn_(1-x)Cd_(x)Se/ZnSe/ZnS/CdZnS QDs.The transitional Zn1 xCdxSe/ZnSe shells serve to effectively suppress heavy hole energy level splitting and weaken the exciton-longitudinal optical phonon coupling of QDs,thus facilitating the formation of highly luminescent QDs with a near-unity photoluminescence quantum yield of 97.8%and narrow emission with a full width at half maximum of 17.1 nm.In addition,the introduction of transitional shells can extend the particle size of QDs to 19.0 nm,which is beneficial for efficient carrier recombination and reduced Joule heating in QD-based LEDs.As a result,the fabricated QLEDs can achieve a record external quantum efficiency of 38.2%,luminance over 120,000 cd m^(-2),and exceptional operational stability T95(tested at 1,000 cd m^(-2))of 24,100 h.These findings provide new ave-nues for synthesizing high-quality QDs with high color purity.
