Pyrochlore-type (K0.73H0.27)NbO3·1.72H2O and (K0.56H0.44)TaO3·1.14H2O were synthesized by a hydrothermal reaction. The K+ ions in these compounds were reacted with Ag+ ions in excess molten AgNO3 at 300°C. This reaction produced fluorite-type Ag0.41Nb0.59O1.68 and pyrochlore-type Ag0.93TaO2.97·0.94H2O. Their crystal structures were refined by the Rietveld method using synchrotron X-ray powder diffraction data. Only the pyrochlore-type Ag0.93TaO2.97·0.94H2O exhibited photocatalytic activity toward phenol degradation under UV light irradiation.
2017 The Ceramic Society of Japan