Synthesis and optical properties of water-soluble CdTe nanocrystals

CdTe nanocrystals were synthesized in aqueous solution with different stabilizers (L-cysteine hydrochloride (L-Cys), 3-mercaptopropionic acid (NIPA), 1-thioglycerol (TG), and thioglycolic acid (TGA)) by a simple route, and were characterized by transit-fission electron microscopy (TEM), X-ray photoelectron spectra (XPS), and Xray diffraction pattern (XRD). The effect of aqueous synthesis conditions on the optical properties of CdTe nanocrystals was investigated and it was found that the molar ratio of Cd/Te, pH value, refluxing time, and different stabilizers significantly affected the optical properties of CdTe nanocrystals. The obtained CdTe nanocrystals exhibited a favorable narrow emission band under different conditions. The photoluminescence (PQ peaks and absorption peaks could be tuned by changing the synthesis conditions of CdTe nanocrystals. Different PL quantum yields (QY) were obtained using different stabilizers. The PL peak position of CdTe nanocrystals did not show significant shift under different excitation wavelengths.