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摘要 Water-soluble CdTe/CdS core-shell quantum dots (QDs) with the different shell thickness capped with 3-mercaptopropionic acid were synthesized following the synthetic method of successive ion layer adsorption and reaction. UV-Vis absorption spectroscopy, photoluminescence (PL) spectroscopy, transmission electron microscopy (TEM) and time-resolved luminescence were employed to analyze optical characters of QDs. The CdTe/CdS QDs exhibited a significant red shift of emission peak, FWHM increasing and PL lifetime lengthening when the shell layer grew. The experiments revealed that the CdTe/CdS QDs evolve from type-I to type-II core-shell structure with the increase of the shell thickness. The lack of PL lifetime lengthening and quantum yield increasing was ascribed to the surface influence of the shell.