Metal ion doped CdSe quantum dots prepared by hydrothermal synthesis: enhanced photocatalytic activity and stability under visible light

Different kind of metal ion doped CdSe quantum dots (QDs) are synthesized by a simple hydrothermal method. The prepared samples are characterized by powder X-ray diffraction, transmission electron microscopy, UV-vis absorption spectra, and X-ray photoelectron spectra (XPS), while the catalytic activities of photocatalysts are tested by photocatalytic degradation of tetracycline hydrochloride under visible-light irradiation. The results show that the 4 mol% Co-doped CdSe QDs exhibit the best photocatalytic activities under visible-light irradiation. While the solution condition is changed to further evaluate their photocatalytic activities, it can be concluded that the existence of cationic surfactant gives the best result and the degradation efficiency is 85.47%. Moreover, there is almost no loss of photocatalytic activities after four cycles. Experimentally and theoretically, this study shows that the method of metal ions doping will be useful for the improvement of photocatalytic activities and stabilities of CdSe QDs.