Novel band gap engineered Bi5Nb3O15/N-rGOcomposite catalyst for photo degradation of reactive dyes

Abstract

Niobate photo catalysts draw significant attention in the fields of both pollutant degradation and H2 generation. However, their chemically inert nature limits the synthetic routes available to obtain these semiconductors. In this work, we report the synthesis of bismuth niobate (Bi5Nb3O15) by a simple solvothermal method and incorporation of this material with nitrogen doped reduced graphene oxide for the first time. The synthesized catalysts were characterized by XRD, Raman, N2 adsorption-desorption isotherm, DRS-UV, FESEM and TEM analyses. XRD patterns exhibited single crystalline orthorhombic structure for Bi5Nb3O15. Electron microscopy showed plate-like structure for Bi5Nb3O15/N-rGO. UV–vis diffuse reflectance spectra revealed red shifting of reduced graphene oxide and nitrogen doped reduced graphene oxide composite catalysts indicating its visible activity. This novel Bi5Nb3O15/N-doped reduced graphene oxide showed higher photocatalytic decolorization of reactive dyes namely reactive blue 19 and reactive orange 16 under visible light than bare Bi5Nb3O15orBi5Nb3O15/rGO.