Fabrication of white light LED photocatalyst ZnO–rGO heteronanosheet hybrid materials

Abstract

ZnO–rGO nanosheets were fabricated using ZnO nanopowder, GO powder and NaOH via a very facile and scalable thermochemical approach. A systematic sample preparation, X-ray diffraction analysis and scanning electron microscopy were conducted to prove the formation of ZnO nanosheet–rGO nanosheet morphology. Moreover, X-ray photoelectron spectroscopy revealed п–п* satellites which is a sign of recovering of aromatic chains of GO while its reduction and ZnO nanosheet formation. The significant shift of Zn 2p3/2 to higher energies proved the hybridization of ZnO with rGO sheets. Transmission electron microscopy demonstrated there is no particle decoration of rGO sheets. The hybrid nanomaterials indicated a spectacular methyl blue degradation under a distant indoor LED light source. Impedance spectroscopy confirmed the enhancement of visible light photo-degradation could be due to enhancement of charge transfer through the catalyst and charge recombination hindrance. Impedance spectroscopy confirmed the enhancement of electron transfer through the structure of nanosheets is the main cause of enhancement of photocatalyst performance of the hybrid materials. BET/BJH analyses revealed an enhancement of surface area and pore size about 134 m2 g−1and 12 nm, respectively which confirms the visible light degradation of MB.