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核壳半导体量子点材料因其在修复单量子点表面缺陷方面的特殊性能,极大地提高了量子点的光学性能而受到人们的研究.改进了CdTe核心的制作方法,使用小型三口瓶替代传统的小烧瓶作为反应容器,制备碲氢化钠,合成了不同核心尺寸、不同壳层厚度与不同壳层材料的10种CdTe/CdS、CdTe/ZnS核壳结构半导体量子点.对10种核壳结构半导体量子点材料进行紫外可见吸收光谱及荧光光谱测试,并分析其荧光特性.量子点在紫外可见波段的吸收光谱表明随着量子点尺寸的增大,吸收峰发生红移.通过实验结果与分析可推断出CdTe/CdS量子点荧光寿命和强度的不同是由于核心和壳层尺寸的不同量子点在Ⅰ型和Ⅱ型中相互转换;CdTe/ZnS的壳层厚度增加时,由于ZnS的壳层降低了核心外表的悬空键和表面缺陷态的数量,使电子空穴对复合机率加大,使得荧光峰位产生了红移.“,”Core-shell semiconductor quantum dots materials are being investigated due to their special performance in repairing surface defects for the single quantum dots and greatly improving the optical performance of quantum dots.Instead of a traditional small flask as a reaction vessel to prepare NaHTe,the preparation of the CdTe core using a three-necked flask was achieved.10 CdTe/CdS and CdTe/ZnS core-shell semiconductor quantum dots with different core sizes,shell thicknesses and shell materials were synthesized.The UV-visible absorption and fluorescence spectrum of 10 kinds of core-shell semiconductor quantum dots materials were measured and analyzed.The absorption spectrum of quantum dots in the UV-visible band shows that with the increase of quantum dots size,the absorption peak is red-shifted.The CdTe/CdS quantum dots differ in fluorescence lifetime and intensity due to the conversion of different core and shell sizes of quantum dots between types Ⅰ and Ⅱ.When the shell thickness of CdTe/ZnS increases,the shell thickness of ZnS reduces the number of dangling bonds and defect states on the core surface,which increases the probability of electron-hole pairs recombination and causes the fluorescence peak red-shift.