Influence of CuO loading on dispersion and reduction behavior of CuO/TiO2 (anatase) system

In this paper, Brunomer-Emmett-Teller (BET) surface area, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and temperature programmed reduction (TPR) are used to investigate the interactions between CuO and the TiO2 (anatase) support, in samples prepared by impregnating the TiO2 support with an aqueous solution of Cu(NO3)(2). 6H(2)O. The results indicate that the surface structure of the TiO2 support has not been changed by supported CuO, and the dispersion capacity of CuO is about 6.98 Cu2+,(TiO2)(-2). The structure of the supported copper oxide species is strongly dependent on the amount of CuO loaded. At low CuO loading, only a highly dispersed surface CuO species is formed on the support and when the CuO loading exceeds its dispersion capacity, crystalline CuO is formed as all the vacant surface sites of the TiO2 support are occupied by Cu2+ ions. In addition, it is found that both the reduction behavior and the crystalline-structure transition of the TiO2 support are related to the interactions between TiO2 and CuO.