水溶性CdTe量子点的合成及影响因素研究

本文以巯基乙酸(TGA)为稳定剂,在水相中合成了高荧光CdTe量子点.其荧光发射波长在507 ～ 628nm范围内可调,最窄半峰宽37 nm,粒径约3.4nm,量子产率达42.1％.本实验在固定前躯体配比不变的情况下,考察了前躯体中镉离子的浓度、pH及回流时间对CdTe生长的影响.并用透射电子显微镜(TEM),荧光分光光度计(FS),X射线衍射仪(XRD)等手段对制备的量子点进行了表征.结果表明:CdTe量子点的尺寸随回流时间而增长；反应的pH对量子点的荧光强度有显著影响；镉离子的浓度越大,量子点的生长速度越快,荧光强度却随之降低.

Synthesis of Water-soluble CdTe Quantum Dots and Its influencing factors

CdTe QDs(Quantum Dots)were synthesized with thioglycolic acid(TGA)as stabilizer in the aqueous phase,which had adjustable emission wavelength in the range of 507~628 nm.The narrowest full width at half maximum(FWHM)was around 37nm and particle size was about 3.4nm.Their yield was up to 42.1%.In this study,the concentration of cadmium ions in the precursor,pH and the refluxing time on the growth of CdTe with fixed ratio of precursor were investigated.And the QDs were characterized by transmission electron microscopy(TEM),fluorescence spectrophotometer(FS),and X-ray diffraction(XRD).The results showed that CdTe QDs were grew with the refluxing time,and the reaction pH had significant impact on the fluorescence intensity.The higher the concentration of cadmium ions had,the faster growth rate got,while the fluorescence intensity decreased.