Hydrothermal Synthesis and Characterization of Bi2Pb2O7 with Pyrochlore Structure

Pyrochlore Bi2Pb2O7 was fabricated under low-temperature hydrothermal conditions and characterized by XRD, IR, SEM DTA–TG, and XPS. XRD analysis shows that the structure of Bi2Pb2O7 is cubic, which is similar to that obtained from highpressure reactions. XPS measurements suggest that the valences of Bi and Pb ions are +3 and +4, respectively. The cubic Bi2Pb2O7 is a metastable phase; it decomposes into a new phase with liberation of O2 at 450°C.