Facile synthesis of SnO2– CuSe nanocomposites with enhanced visible light photocatalytic performance

Abstract

Wastewater treatment is currently one of the key topics addressing environmental-related challenges for the betterment of our lives. We report a comparative study on the photocatalytic properties of SnO2–CuSe nanocomposites with varying amounts of CuSe. The samples were prepared by simple and cost-effective hydrothermal and chemical methods. X-ray diffraction (XRD), Raman spectroscopy, and energy dispersive X-ray spectroscopy (EDAX) analysis confirmed the successful fabrication of the samples without any impurities. The average crystallite sizes were respectively determined to be around 23 and 26 nm for SnO2 and CuSe respectively. For the SnO2–CuSe nanocomposites, the crystallite sizes were calculated to be in the range of 20–28 nm. Field emission scanning electron microscopy (FE-SEM) images revealed a flower-like morphology for the SnO2, whilst the shape of pure CuSe is found to be of irregular plates. Similarly, the SnO2–CuSe nanocomposites exhibited coexisting flower-plates-like morphology dependent on the CuSe content. Electron Resonance Spectroscopy (ESR) also revealed paramagnetic defects in the prepared samples. UV–visible absorption measurements showed a red shift in the bandgap energy with increasing the CuSe content in the nanocomposite samples. The photocatalytic performance of the fabricated samples was determined by taking Rhodamine B (RhB) as a model dye. The nanocomposite sample with the composition of SnO2-32% CuSe showed the best photocatalytic performance. The Langmuir-Hinshelwood model was applied to determine the apparent rate constants.