Effects of Ni doping contents on photocatalytic activity of B-BiVO4 synthesized through sol-gel and impregnation two-step method

To enhance the photocatalytic activity of B-BiVO4, Ni-doped B-BiVO4 photocatalyst (Ni-B-BiVO4) was synthesized through sol-gel and impregnation method. The photocatalysts were characterized by XPS, XRD, SEM, EDS, BET and UV-Vis DRS techniques. The results showed that single or double doping did not change the crystalline structure and morphology, but the particle size decreased with Ni doping. The band gap energy absorption edge of Ni-B-BiVO4 shifted to a longer wavelength compared with undoped, B or Ni single doped BiVO4. More V4+ and surface hydroxyl oxygen were observed in BiVO4 after Ni-B co-doping. When the optimal mass fraction of Ni is 0.30%, the degradation rate of MO in 50 min is 95% for 0.3Ni-B-BiVO4 sample which also can effectively degrade methyl blue (MB), acid orange (AOII) II and rhodamine B (RhB). The enhanced photocatalytic activity is attributed to the synergistic effects of B and Ni doping.