Ion state of atoms and the properties of perovskite-like compound CaCu3V4O12

The binding energies and valence state of atoms in the perovskite-like compound CaCu3V4O12 have been determined using XPS spectroscopy. The stoichiometry of this phase is formulated as Ca2+Cu2+Cu2+(V25+V24+O12). Under an air atmosphere, the phase interacts with water vapor and oxygen. As a result, Ca(OH)2 is formed on its surface, the Cu+ and V4+ ion concentrations decrease, and the Cu2+ and V5+ concentrations increase in association. Raman spectra show shortened cation-anion bond lengths and cation-anion-cation bond angles in CaCu3V4O12 compared to perovskite CuVO3; the two structures are alike. The electrical conductivity, magnetic susceptibility, thermal and sensor properties of CaCu3V4O12 in aqueous salt solutions have been studied.