Preparation of Fe2(MoO4)3/graphene/Ti nanocomposite electrode for visible-light photoelectrocatalytic degradation of organic pollutants

Abstract

The massive emission of organic pollutants, specially organic dyes into water poses a serious threat to the environment and human health. Photoelectrocatalysis (PEC) has been regarded as an efficient, promising and green technology for organic pollution degradation and mineralization. Herein, Fe2(MoO4)3/graphene/Ti nanocomposite was synthesized and applied as a superior photoanode in a visible-light PEC process for degra-dation and mineralization of an organic pollutant. First, the Fe2(MoO4)3 was synthesized by the microemulsion-mediated method. Then, Fe2(MoO4)3 and graphene particles were simultaneously immobilized on a titanium plate by the electrodeposition technique. The prepared electrode was characterized by XRD, DRS, FTIR and FESEM analyses. The ability of the nanocomposite was investigated in the Reactive Orange 29 (RO29) pollutant degradation by the PEC. The Taguchi method was used for the visible-light PEC experiments design. The effi-ciency of RO29 degradation was enhanced with increasing bias potential, number of Fe2(MoO4)3/graphene/Ti electrodes, visible-light power and Na2SO4 (electrolyte) concentration. The pH of the solution was the most influential variable in the visible-light PEC process. Furthermore, the performance of the visible-light PEC was compared with photolysis, sorption, visible-light photocatalysis and electrosorption processes. The obtained results confirm the synergistic effect of these processes on RO29 degradation by the visible-light PEC.