A comparative study of reduced graphene oxide modified TiO2, ZnO and Ta2O5 in visible light photocatalytic/photochemical oxidation of methylene blue

Sun, Hongqi and Liu, Shizhen and Liu, Shaomin and Wang, Shaobin. 2014. A comparative study of reduced graphene oxide modified TiO2, ZnO and Ta2O5 in visible light photocatalytic/photochemical oxidation of methylene blue. Applied Catalysis B: Environmental. 146: pp. 162-168.

Source Title

Applied Catalysis B: Environmental

DOI

10.1016/j.apcatb.2013.03.027

ISSN

09263373

Remarks

NOTICE: This is the author’s version of a work that was accepted for publication in Applied Catalysis B: Environmental. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Applied Catalysis B: Environmental, Volume 146, March 2014, Pages 162–168. http://dx.doi.org/10.1016/j.apcatb.2013.03.027

URI

http://hdl.handle.net/20.500.11937/45273

Collection

Curtin Research Publications

Abstract

Reduced graphene oxide (rGO) was applied to prepare various composites of rGO/photocatalyst of G/TiO2, G/ZnO and G/Ta2O5, using titanium (IV) isopropoxide, Zn powder and commercial Ta2O5 powder as photocatalyst precursors, respectively. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric-differential thermal analysis (TG-DTA) and UV–vis diffuse reflectance (UV–vis DRS) were employed to investigate the crystal structure, morphology, surface groups, rGO loading, and optical properties of the produced composites. The photocatalytic activities of the composites under UV–vis and visible light were studied in degradation of methylene blue (MB). G/Ta2O5 showed an enhanced efficiency under UV–vis irradiation. G/TiO2 demonstrated an effective degradation of MB under visible light. The effects of various oxidants, peroxymonosulfate (PMS), peroxydisulfate (PDS) and hydrogen peroxide (H2O2) on MB degradation were thoroughly investigated. H2O2 was a promising oxidant for promoting MB degradation under visible light. The mechanism of the enhanced efficiency in the system of G/TiO2+ vis + H2O2 was discussed.