Two-dimensional CuO-ZnO nanohybrids with enhanced photocatalytic performance for removal of pollutants

Abstract

Two dimensional (2D) CuO-ZnO hybrid nanostructures were prepared by using a simple chemical approach and thoroughly investigated by FESEM, X-ray photoelectron spectroscopy, HRTEM, UV–Vis absorption spectroscopy and X-ray diffraction. The photocatalytic decomposition of organic dyes was evaluated using the prepared 2D CuO-ZnO hybrid nanostructures as photocatalysts under sunlight irradiation. Photocatalytic degradation assisted by 2D CuO-ZnO nanohybrids showed remarkably improved efficiency than pristine nanosheets of CuO and completely decolorized MB and MO dyes in just 20 min. Photocatalytic degradation of toxic 4-nitrophenol (4-NP) was also investigated in the presence of prepared nanostructures and 2D CuO-ZnO nanohybrids illustrated better activity over pristine CuO nanosheets. The observed superior photocatalytic performance of 2D CuO-ZnO nanohybrids is ascribed to the inhibited charge carrier recombination and improved light utilization because of formation of p-n nanoheterojunctions of CuO and ZnO. A possible mechanism and role of radicals participating in photocatalytic degradation of dyes were also proposed.