Preparation and characterization of Ni-doped ZnO-SnO2 nanocomposites: Application in photocatalysis

The paper reports on the synthesis of nickel-doped ZnO-SnO2 nanocomposites with a molar ratio Zn:Sn of 2:1 using the hydrothermal method followed by calcination at 700 degrees C. The resulting nanocomposites were characterized using X-ray diffraction (XRD) patterns, transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and Energy-dispersive X-ray spectroscopy (EDX). The results revealed that the NianO-SnO2 material consists of aggregated cassiterite SnO2 and wurtzite ZnO nanoparticles (NPs) with a size ranging from 14 to 40 nm. Furthermore, they show that Ni adding induces a dominant effect on the optical, structural and morphological properties of ZnO-SnO2 NPs. The photocatalytic behavior of the synthesized nanocomposites is investigated using rhodamine B (RhB) as model organic pollutant. A maximum degradation efficiency of 96% is achieved under visible light irradiation. While nickel doping did not enhance the photocatalytic activity of ZnO-SnO2 NPs, the photocatalytic performance of NignO-SnO2 NPs is much higher than that of Ni-doped ZnO NPs. The photodegradation mechanism is believed to occur through photosensitization. (C) 2016 Elsevier Ltd. All rights reserved.