Synthesis of M(M=Co2+,Co2+/Ni2+)-doped FeS2 Nanospheres with Enhanced Visible-light-induced Photocatalytic Activity

Nano-spherical Co2+-doped FeS2was synthesized through a simple solvothermal method. The products were investigated using XRD, FE-SEM, BET, ICP, EDS, TEM, HRTEM, XPS, and UV-vis spectroscopy. The results indicated that Co2+ion could change the particle nucleation process and inhibited the particle growth of FeS2. In addition, when the content of doped Co2+was 15%, the degradation efficiency of methylene blue(MB) achieved 60.72% after 210 min irradiation, which increased by 52.01% than that of the undoped FeS2. Moreover, comparison experiments also demonstrated that the M(M=Co2+, Co2+/Ni2+)-doped FeS2photocatalytic activity efficiency sequence was Co2+> Ni2+>Co2+/Ni2+. This is ascribed to the fact that the Co2+doping could induce the absorption edge shifting into the visible-light region and increased the surface area of the samples. The effect mechanisms of M-doping on the band gap and the photocatalytic activity of FeS2were also discussed.