A novel composite photocatalyst based on in situ growth of ultrathin tungsten oxidenanowires on graphene oxide sheets

Abstract

Graphene oxide sheets were initially prepared by a modified pressurized oxidation method. Through a one-pot solvothermal route, a novel composite photocatalyst based on in situ growth of ultrathin W₁₈O₄₉ nanowires with diameters of 2–3 nm on graphene oxide sheets was then successfully fabricated. The as-prepared graphene oxide sheets and W₁₈O₄₉–reduced graphene oxide composite have been systematically characterized by combined techniques of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman microscopy, X-ray photoelectron spectrometry, and UV-vis diffuse reflectance spectroscopy. Compared to the W₁₈O₄₉ nanoflowers prepared in the absence of graphene oxide sheets, the W₁₈O₄₉–reduced graphene oxide composite exhibited significantly enhanced photocatalytic properties for the decomposition of methyl orange solution and for the growth inhibition of V. natriegens under full spectrum light, which is mainly due to the strong coupling interaction between the W₁₈O₄₉ nanowires and the reduced graphene oxide sheets. The present solvothermal process simultaneously enables the reduction of graphene oxide and the formation of W₁₈O₄₉, making it suitable for the preparation of other graphene-based composites.