抄録
An iron phosphate gel prepared in organic solvents by the sol-gel method was heated in vacuo, and the structure, valence of the iron atoms, and electrical conductivity were investigated. It was found that the iron phosphate (FePO4) gel containing carbonaceous deposits is easily reduced by heating in vacuo above 500°C and crystallized as Fe2P2O7. The gels evacuated at 500°C and 700°C contained different valence iron atoms, Fe2+ and Fe3+, and showed semi-conductive characteristics. The electric conductivity of the gel evacuated at 700°C was lower than that of Cr2O3, but higher than CoO.
