Facile preparation of immobilised visible light active W–TiO /rGOcomposite photocatalyst by plasma electrolytic oxidation process

Abstract

A highly efficient immobilised W–TiO/rGO composite photocatalyst was prepared as a coating on titaniumusing plasma electrolytic oxidation (PEO) with particle addition. The high dopant concentration in TiO resulted in smaller crystallite size , increased lattice strain, and dislocation density. The optimum Wcontaining G6W sample has improved electron mobility, higher charge carrier separation efficiency, andlower electron-hole recombination rate. This can be ascribed to the number of different defect centresemerging from tungsten interstitials and higher oxygen vacancies in the TiO structure. The catalystexhibited enhanced photocatalytic degradation efficiency (93%) of methylene blue dye than the pure TiO ,which was attributed to the synergetic effect of 2-D structured rGO and the changes incorporated upon tungsten interstitials in the TiO. The present research concludes that W–TiO/rGO photocatalyst by PEOprocess can be a good candidate for efficient, low cost, reusable, and visible-light-driven immobilisedphotocatalyst for textile wastewater treatment.