Potential visible WO 3/ GO composite photocatalyst

Abstract Graphene oxide ( GO ) was synthesized by Hummers method. GO and tungsten oxide ( WO ₃ ) composites were successfully prepared by deposition of WO ₃ on GO surface to make efficient visible light catalyst. Scanning electron microscopy of pure GO revealed that GO films are folded with kinked and wrinkled edges. The interspaces layers are partially filled by WO ₃ nanoparticles with their less wrinkled edges and smooth surface of composite. Moreover, composite sheets are thin and transparent which allow easy penetration of light. EDS showed the presence of C, O, and W in GO / WO ₃ composites with no impurity. UV ‐Vis diffused reflectance spectra showed red shift with the increase in WO ₃ contents. Raman spectra of GO and GO / WO ₃ composite show G and D bands. These bands reduced in intensity in composite sample due to removal of oxygenated functional groups with some new peaks of WO ₃ . FT ‐ IR confirmed successful oxidation of graphite into GO with reduction in GO because oxide‐related bond groups decrease after reduction. The transmittance peaks of WO ₃ in composite sample are appeared indicating W‐O‐C linkages. The highest visible light activity of the composite is due to easy penetration of light with deposition of WO ₃ , low band gap, and new linkages.