Synthesis of butterfly-like BiVO4/RGO nanocomposites and their photocatalytic activities

A simple and high efficient method was proposed for the synthesis of uniform three dimensional (3D) BiVO4/reduced graphene oxide (RGO) nanocomposite photocatalyst by adopting the microwave assistant and using Bi(NO3)3·5H2O, graphene oxide (GO) and NH4VO3 as precursor. The as-obtained composites were well characterized with the aid of various techniques to study the morphology, structure, composition, optimal and electrical property. In the as-obtained composites, the GO sheets were fully reduced into RGO, and monoclinic structure BiVO4 crystallized completely into butterfly-like BiVO4 lamellas and well bonded with the RGO lamellas. The length and the width of the butterfly-like BiVO4 particle were about 1.5 μm, and the thickness of the flake was about 20 nm. Photocatalytic performances of BiVO4/RGO composite and pure BiVO4 particle have been evaluated by investigating the reduction of Cr(VI) ion-contained wastewater under simulated solar light irradiation, where the BiVO4/RGO composite displayed enhanced photocatalytic activity. It is found that the pseudo-first-order rate constants (k) for the photocatalytic reduction of Cr (VI) by BiVO4/RGO composite was about 4 times as high as that of the pure BiVO4. The present work suggested that the combination of BiVO4 and RGO displayed a remarkable synergistic effect, which led to enhanced photo-catalytic activity on Cr(VI) reduction.