Enhanced photocatalytic properties of CuO-ZnO nanocomposites by decoration with Ag nanoparticles

Rational design of multi-component heterostructure photocatalyst is capable of combining the advantages of the different components. Here, a ternary CuO-ZnO-Ag nano-composite was fabricated by a facile sol-gel method for the photodegradation of organic dye pollutants in wastewater. Decorating Ag NPs on the surfaces of CuO-ZnO nanocomposites improves their photocatalytic activities, which can be further enhanced by tuning the Ag loading level. At 2 mol%, the photocatalytic degradation efficiencies of CuO-ZnO nanocomposites for methylene blue (MB), methyl orange (MO), rhodamine b (RhB) under simulated sunlight irradiation, and for MB under visible light irradiation are increased by 42%, 42%, 63% and 78%, respectively. The enhanced efficiencies can be attributed to the strengthened visible light absorption and the lower recombination rate of photogenerated electron-hole pairs. This work will trigger an inspiration for lowering the dosage of noble metal in photocatalyst by building the simple multiheterostructure consisting of the low-cost metal elements.