Da Silva, Wallace J.C.Da Silva, Marcelo R. [UNESP]Takashima, Keiko2022-04-282022-04-282015-12-01Journal of the Chilean Chemical Society, v. 60, n. 4, p. 2749-2751, 2015.0717-97070717-9324http://hdl.handle.net/11449/220567Zinc oxide, an n-type semiconductor, has been used as photocatalyst for contaminated water purification by organic compounds. The addition of a p-type semiconductor as copper oxide could increase the catalytic efficiency through the p-n junction in order to decrease the electron-hole recombination. In this work, zinc and copper oxides containing 1.0, 3.0, and 5.0 % of copper were prepared by manual grinding, followed by heat treatment at 300C during 5 h. The zinc oxide and copper oxide mixture as well as their precursors were characterized by x-ray diffraction, diffuse reflectance, scanning electron microscopy, and x-ray fluorescence. The photocatalytic efficiency was verified by the direct red 80 tetraazodye decolorization using UV radiation under pseudo-first order conditions at natural pH (7.5-8.0) and 30 °C. The highest photocatalytic activity occurred to the semiconductor containing 1.0 % copper oxide, whose decolorization rate constant was equivalent to 6.40×10-2min-1, that is, 17.4 % larger in comparison to ZnO, 5.45×10-2min-1.2749-2751engCharacterizationCopper oxideDirect red 80Heterogeneous photocatalysisZinc oxideArtigo10.4067/s0717-970720150004000222-s2.0-84959357907