Formation behavior of CaCu3Ti4O12 from CaTiO3, CuO and TiO2

The formation behavior of CaCu3Ti4O12 (CCTO) had been investigated via solid state reaction from CaTiO3, CuO and TiO2 powders. In the temperature range from 750 to 1,200 °C, the reaction sequence was traced by XRD, and the microstructure evolution of calcined powders was also investigated by SEM. CCTO began to form owing to the reaction between CaTiO3, CuO and TiO2 at around 850 °C, and became the major phase at 1,000 °C. Finally, the single phase CCTO was obtained at 1,150 °C. However, CCTO was decomposed at CaTiO3, CuO and TiO2 when the temperature increased to 1,200 °C. In addition, no other intermediate phases occurred in the synthesized process. The formation behaviors indicated that CaTiO3 prevented the formation and growth of CCTO.