UV-assisted synthesis of reduced graphene oxide–ZnO nanorod composites immobilized on Zn foil with enhanced photocatalytic performance

Abstract

ZnO nanorods were hydrothermally grown on Zn foil in an alkaline solution and the immobilized nanorods were subsequently hybridized with reduced graphene oxide (rGO) through UV-assisted photocatalytic reduction of graphene oxide (GO). X-ray diffraction analysis confirmed the vertical growth of ZnO nanorods while the incorporation of rGO to ZnO was investigated by scanning electron microscopy and photoluminescence spectroscopy. The successful photocatalytic reduction of GO was demonstrated by means of Raman spectroscopy and X-ray photoelectron spectroscopy. The photocatalytic behavior and photostability of the sandwich-like rGO–ZnO composite were studied through decolorization of the aqueous solution of acid orange 7 under UV-C illumination. The rGO–ZnO photocatalyst presented higher dye decomposition efficiency than pure ZnO. The hybridization of rGO and ZnO led to a 40 % increase in the pseudo-first-order kinetic model’s rate constant and an enhancement of the photostability. The role of incorporation of rGO in enhancement of the ZnO’s photostability has been elucidated in the light of specific features of the sandwich-like architecture.