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.