以巯基丙酸(mercaptopropionic acid,MPA)作为稳定剂,在水相中合成Cu离子掺杂的ZnSe量子点(quantum dots,QDs),并以ZnTe修饰其表面(ZnSe:Cu/ZnTe QDs).采用X射线衍射(X-ray diffraction,XRD)、高分辨透视电子显微镜(high resolution transmission electronic microscopy,HRTEM)、紫外可见吸收光谱(ultraviolent-visible spectroscopy,UV-VIS)和光致发光(photoluminescence,PL)荧光光度计对其结构、相貌和光学特性进行表征.结果表明,合成所得荧光量子点的大小为4~6 nm;当激发波长325 nm时,荧光发射峰约为510 nm;经160 ℃热处理后,荧光发射峰会红移至540 nm左右,初步说明ZnTe的修饰会改变ZnSe:Cu量子点荧光发射峰的位置.
This paper studies synthesis of ZnSe quantum dots (QDs) doped with Cu ion in an aqueous solution by using 3-mercaptopropionic acid (MPA) as ligand, and then modified its surface by ZnTe (ZnSe:Cu/ZnTe). The structure, morphology and optical properties of QDs are characterized with X-ray diffraction (XRD), high resolution transmission electronic microscopy (HRTEM), ultraviolent-visible spectroscopy (UV-VIS) and photoluminescence (PL) spectroscopy. The sizes of QDs obtained were 4~6 nm. Under an excitation wavelength of 325 nm, peaks of ZnSe:Cu/ZnTe at 510 nm were observed. Especially, the peaks moved to 540 nm after a heat processing at 160 ℃. The facts indicate that the fluorescence emission peak’s positions of ZnSe:Cu QDs capped by ZnTe surface modification can be changed.
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