CuInS_(2)/ZnS核壳结构量子点的制备与性能研究

Study on Synthesis and Properties of CuInS_(2)/ZnS Core/Shell Quantum Dots

采用两步法制备CuInS_(2)/ZnS核壳结构量子点,研究了一锅煮法制备CuInS_(2)量子点的反应温度和反应时间对其晶体结构、微观形貌和光学性能的影响以及Cu/Zn摩尔比和反应时间对CuInS_(2)/ZnS核壳结构量子点的晶体结构和光学性能的影响。结果表明:所制备的CuInS_(2)量子点为黄铜矿结构,随着反应温度和反应时间的增加,XRD衍射峰的强度增大,光学带隙由3.48eV逐渐减小到3.38eV,荧光发射峰由646nm红移至702nm。所制备的CuInS_(2)/ZnS核壳结构量子点的XRD衍射峰随着Cu/Zn摩尔比的增加从低衍射角CuInS_(2)的衍射峰向高衍射角ZnS的衍射峰方向偏移,特征衍射峰的强度先增大后减小,光学带隙宽度从3.51eV增大到3.63eV,荧光发射峰与CuInS_(2)量子点荧光发射峰比较,荧光发射峰波长由646nm移动到616~607nm的波长范围,发生明显蓝移,量子点的荧光发射峰的强度显著增强。随着反应时间的增加,CuInS_(2)/ZnS核壳结构量子点的光学带隙逐渐增大,荧光发射峰发生蓝移。

The CuInS_(2)/ZnS core-shell structure quantum dots were prepared by a two-step method.The effects of reaction temperature and reaction time on the crystal structure,micro-morphology,and optical properties of CuInS_(2)quantum dots prepared by one-pot method,and the effects of Cu/Zn molar ratio and reaction time on crystal structure and optical properties of CuInS_(2)/ZnS core-shell quantum dots were investigated.The experimental results show that CuInS_(2)quantum dots with tetragonal chalcopyrite structure have prepared.With the increase of reaction temperature and reaction time,the intensity of XRD diffraction peaks,the optical band gap gradually decreases from 3.48 eV to 3.38 eV,and the fluorescence emission peak red-shifts from646 nm to 702 nm.With the increase of Cu/Zn molar ratio,the XRD diffraction peaks of the prepared CuInS_(2)/ZnS core-shell structure quantum dots shift from the low diffraction angle CuInS_(2)diffraction peak to the high diffraction angle ZnS diffraction peak,the optical band gap width increases from 3.51 eV to 3.63 eV.Compared with the fluorescence emission peak of CuInS_(2)quantum dots,the fluorescence emission peak moves from the wavelength of 646 nm to the wavelength range of 616 nm to 607 nm,and a significant blue shift occurs,the intensity of the fluorescence emission peak of quantum dots is significantly enhanced.With the increase of reaction time,the optical band gap of CuInS_(2)/ZnS core-shell structure quantum dots gradually increases,and the fluorescence emission peak shifts blue.