Preparation,Characterization and Photocatalytic Performance of Al~(3+) Doped ZnS Nanocrystals

Under mild condition,a series of Al3 +doped ZnS nanocrystals were prepared by a solvothermal method with ethylene glycol as the reaction medium and zinc acetate(Zn(CH 3 COO) 2 ·2H 2 O),thiourea((NH 2) 2 CS) and aluminum nitrate nonahydrate(Al(NO 3) 3) as the precursors.The obtained ZnS nanocrystals were characterized by N 2 physical adsorption,scanning electron microscopy(SEM),X-ray diffraction(XRD),UV-vis diffuse reflectance spectra(UV-vis DRS),fourier transform infrared(FT-IR) spectrophotometer and photoluminescence(PL) spectroscopy.The effects of Al3 +doping with different content on the crystallinity,surface area,surface groups,light adsorption and photocatalytic performance in degradation of different dyes were investigated.The results show that at the mild temperature of 140 ℃,the prepared spherical Al3 +doped ZnS nanocrystals show high crystallinity.Al3 +doping results in an increase in surface area and a higher level of surface hydroxyl groups.A lower recombination rate of photogenerated hole-electron(e-/ h+) pairs was also observed over Al3 +doped ZnS.Doping optimum content of Al3 +(6% mol) brings about 3.5,1.0 and 0.9 times increase in degradation rates of the dyes of acid orange II,methylene blue,and rhodamine B,respectively.