CuO@ZnO core-shell nanocomposites: Novel hydrothermal synthesis and enhancement in photocatalytic property

The efficient charge separation and interfacial charge transfer in the semiconductors are of great significance to photocatalytic performance. Herein, we report a facile and cost-effective synthesis of the CuO@ZnO core-shell nanocomposites with the aim to enhance the catalytic activity of ZnO in photodegradation of methylene blue (MB) under UV irradiation. Using a simple two-step hydrothermal method, CuO nanostructures with different thicknesses are grown on ZnO nanoparticles (0.4, 2, 10 and 50% with respect to the ratio of initial molar concentrations of copper to zinc). Significant improvement in the photocatalytic efficiency was observed with utilizing 0.4 and 2%CuO@ZnO nanocomposites compared to the pristine ZnO nanoparticles. The structural and optical properties of the as-prepared samples were investigated by XRD and DRS analysis, respectively. Further, the morphology of the as-synthesized nanostructures was studied by FESEM and TEM imaging, and the high purity and the characteristic functional groups of the final products were also explored using EDX and FTIR spectroscopies, respectively.