Novel ZnO/CuBi2O4 heterostructures for persulfate-assisted photocatalytic degradation of dye contaminants under visible light

New visible-light-induced photocatalysts were synthesized through a hydrothermal method, which possess excellent activation efficiency for potassium persulfate (PS) to remove water contaminants. The features of as-synthesized nanocomposites were studied by different instruments. The results showed that the binary ZnO/CuBi2O4 (5.0 %) sample has best photocatalytic capability in the elimination of methyl orange (MO), rhodamine B (RhB), and Congo red (CR). The photodegradation rate constant of RhB over the ZnO/CuBi2O4 (5.0 %) photocatalyst in the existence of 1.48 mM of PS ions, was 178 x 10(-4) min(-1), which is about 26.4, 5.11, 4.31, and 2.44-times as large as the pristine ZnO, PS ions, ZnO/PS, and ZnO/CuBi2O4 (5.0 %) nanocomposite, respectively. The improving photodegradation efficiency was attributed to larger surface area, high absorption of visible light, and the formation of heterojunction at the interface of ZnO and CuBi2O4 nanoparticles. In our view, this study supplies a new method for the production of effective heterojunction photocatalysts using ZnO, which could solve environmental problems according to the practical requirements.