Preparation of three dimensional graphene foam–WO3 nanocomposite with enhanced visible light photocatalytic activity

Abstract

Three dimensional graphene foam (3D GF) was synthesized by chemical vapor deposition (CVD) on a nickel foam skeleton. After dissolving the nickel foam, the obtaining 3D GF was used as a highly porous conductive substrate for nucleation and growth of WO3 particles. Scanning electron microscopy (SEM) and Raman spectroscopy was employed to ensure the quality of the prepared GFs and to judge about the 3D GF–WO3 chemical structure. The WO3 characteristic Raman peaks centered at 726, and 809 cm−1 are slightly broadened and displaced to lower wavelength in the 3D GF–WO3 nanocomposite, as compared to the corresponding peaks of the bare tungsten oxide. This phenomenon confirms the formation of W–C and W–O–C bonds in composite material which is important for faster transferring the photoexcited electrons to graphene 3D network as an exceptional electron acceptor. The 3D GF−WO3 composite material was applied in photocatalytic degradation of Rhodamine B dye. It was observed that the annealed samples show an excellent photocatalytic performance relative to the as-prepared 3D GF−WO3 samples and bare WO3, which is ascribed to the lower electron/hole recombination through the formation of W–C and W–O–C bonds.