Self-assembly and enhanced visible-light-driven photocatalytic activity of reduced graphene oxide-Bi2WO6 photocatalysts

The reduced graphene oxide-Bi2WO6 (rGO-BWO) photocatalysts with different RM values (mass ratio of GO and Bi2WO6) had been successfully synthesized via hydrothermal method in the presence of GO. When increasing the RM values from 0 to 2%, the evident red shift of the absorption edges of rGO-BWO samples occurred, and the photocatalytic activities for the degradation of Rhodamine-B were enhanced gradually. However, there was a significant blue shift in the absorbance band, and the morphology of the incomplete rGO-BWO microspheres led to the lower photocatalytic activity when RM is increased from 4 to 10%. The enhanced photocatalytic activity can be attributed to the smaller band gap, which means needing less energy for the electron transition, the morphology of the unbroken microsphere that provides more possible reaction sites for the photocatalytic reaction, the appropriate GO content that may effectively mitigate electron-hole pair recombination by the migration of photoinduced electrons