中文摘要：

利用X射线衍射谱（XRD）、紫外-可见（UV—Vis）吸收光谱、荧光光谱（PL）系统地研究了不同表面、多种尺寸的CdSe半导体量子点（QDs）的光学性质、结果显示表面修饰完善的样品的荧光光谱只有一个窄而强的带边发射；所有样品的荧光峰相对于1S-1S吸收峰有较大的红移，并且移动量随尺寸的减小而增加，利用激子的精细结构模型很好地解释了红移量和尺寸的关系；核／壳结构的样品的吸收峰和荧光峰相对于同尺寸的单量子点也有红移现象，这是由于CdSe和ZnS的晶格失配在界面上产生压力造成的。

英文摘要：

Size-dependent properties of CdSe and CdSe/ZnS semiconductor quantum dots were studied by X-ray diffraction （XRD）, UV-Vis absorption and photoluminescence （PL）. XRD showed hexagonal wurtzite structure. Room-temperature PL spectra of perfectly overcoated CdSe/ZnS only showed a narrow band edge emission. Emission peak was great red-shifted relative to absorption and the shift increases as the size decreases. The size-dependence of shift could be explained very well in terms of excition fine-structure model and stress at interface owing to lattice mismatch contributes to the shift between CdSe and CdSe/ZnS with the same size.