Ternary polyaniline–graphene–TiO2 hybrid with enhanced activity for visible-light photo-electrocatalytic water oxidation

Abstract

A polyaniline–graphene–TiO₂ (PANI–GR–TiO₂) hybrid has been successfully synthesized by coating graphene nanosheets (GR) on the surface of TiO₂ and the subsequent chemical polymerization of aniline. The synthesized ternary PANI–GR–TiO₂ was thoroughly studied by using scanning electron microscopy (SEM), Raman spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The PANI–GR–TiO₂ hybrid displays promising oxygen evolution reaction (OER) activity for photoelectrocatalytic water oxidation. Moreover, the durability of the ternary hybrid was greatly improved due to the coating of PANI and GR on the surface of TiO₂. Finally, a reasonable mechanism was proposed to understand the enhanced activity of the PANI–GR–TiO₂ hybrid using UV-Vis absorption spectroscopy and photoluminescence (PL) emission spectroscopy. Our results clearly demonstrate that integrating GR and PANI with TiO₂ through a simple route results in an efficient ternary photocatalyst with prominent OER performance for visible-light photoelectrocatalytic water oxidation.