Degradation of organic dyes using spray deposited nanocrystalline stratified WO3/TiO2 photoelectrodes under sunlight illumination

Abstract The need to utilize TiO 2 based metal oxide hetero nanostructures for the degradation of environmental pollutants like Rhodamine B and reactive red 152 from the wastewater using stratified WO 3 /TiO 2 catalyst under sunlight illumination. WO 3 , TiO 2 and stratified WO 3 /TiO 2 catalysts were prepared by a spray pyrolysis method. It was found that the stratified WO 3 /TiO 2 heterostructure has high crystallinity, no mixed phase formation occurs, strong optical absorption in the visible region of the solar spectrum, and large surface area. The photocatalytic activity was tested for degradation of Rhodamine B (Rh B) and reactive red 152 in an aqueous medium. TiO 2 layer in stratified WO 3 /TiO 2 catalyst helps to extend its absorption spectrum in the solar light region. Rh B and Reactive red 152is eliminated up to 98 and 94% within the 30 and 40 min respectively at optimum experimental condition by stratified WO 3 /TiO 2 . Moreover, stratified WO 3 /TiO 2 photoelectrode has good stability and reusability than individual TiO 2 and WO 3 thin film in the degradation of Rh B and reactive red 152. The photoelectrocatalytic experimental results indicate that stratified WO 3 /TiO 2 photoelectrode is a promising material for dye removal.