Spray deposited Fe2O3 and stratified Fe2O3/ZnO novel photoelectrode for photoelectrocatalytic degradation of benzoic acid under solar light illumination

Abstract

Fe2O3 and stratified Fe2O3/ZnO thin films are successfully synthesized by chemical spray pyrolysis technique. Synthesized films are used to study the photoelectrochemical (PEC), structural, morphological and optical properties. The maximum PEC response is observed for stratified Fe2O3/ZnO photoelectrode (Isc = 0.850 mA and Voc = 948 mV). All the films are polycrystalline nature with rhombohedral and hexagonal crystal structures for Fe2O3 and ZnO phase respectively is conformed from XRD analysis. Surface morphology of stratified Fe2O3/ZnO film shows the cluster of petal like grains on the surfaces of film. The estimated band gap energy of prepared Fe2O3 and stratified Fe2O3/ZnO thin films are 2.10 and 2.65 eV respectively. Finally large area (100 cm2) deposited Fe2O3 and stratified Fe2O3/ZnO photoelectrodes are used to study the photoelectrocatalytic degradation of benzoic acid (BA) under solar radiation. The higher degradation result is observed in case of stratified Fe2O3/ZnO than Fe2O3 photoelectrode and it is about 74% in 320 min. The mineralization of BA in aqueous solution is study with the help of chemical oxygen demand (COD). The observed results indicate that stratified Fe2O3/ZnO photoelectrode is promising candidate for degradation of BA.