A mesoporous nanofibrous BiVO4-Ni/AgVO3 Z-scheme heterojunction photocatalyst with enhanced photocatalytic reduction of Cr6+ and degradation of RhB under visible light

In this study, we fabricated a novel heterostructured BiVO4-Ni/AgVO3 nanofibers by combining the electrospinning approach and hydrothermal method. Benefiting from the synergetic strategy of Ni doping and AgVO3 coupling, the specific surface area and visible-light absorption of BiVO4-Ni/AgVO3 were both increased compared to BiVO4. Meanwhile, the separation efficiency of photogenerated carriers was effectively improved through the formed impurity energy level and heterojunction. As a result, the optimal BiVO4-Ni-1/AgVO3-25 photocatalyst exhibited excellent photocatalytic reduction efficiency of 99.7% towards Cr6+ within 80 min, and also displayed superior degradation efficiency of 98.6% towards RhB within 30 min. Moreover, a Z-scheme charge transfer mechanism was explained for BiVO4-Ni/AgVO3 according to the radical trapping experiments and band matching. The successful preparation of Z-scheme heterojunction BiVO4-based photocatalyst has essential application prospects in photocatalytic degradation of pollutants and reduction of metal ions.