2020 年 128 巻 10 号 p. 747-755
Next-generation ceramic devices will have to be fabricated by novel sintering techniques if they are to obtain the requisite properties such as lightness, robustness, and flexibility. To bind with polymer materials, ceramics must be sintered at temperatures of under 300 °C. In this study we developed a number of low-temperature sintering techniques to synthesize complex oxides by exploiting the chemical reactions among the raw material components. We also developed a number of novel low-temperature synthesis processes to utilize the aforesaid synthesis reactions in sintering. Complex oxides can be prepared at low-temperature using hydroxide and peroxide raw materials. Notably, we found that perovskite oxides, including alkaline earth oxides, can be prepared at temperatures below 100 °C using hydroxide raw materials. (Ba,Sr)(Co,Fe)O3 can be sintered as a cathode material on solid oxide fuel cells at 700 °C by reactive sintering using the solid state synthesis reaction among the peroxide-and-hydroxide mixtures. Cells produced by this method show superior electrochemical performance attributable to an improved interface on the cathode layer derived from reactive sintering. We also found that the novel low-temperature synthesis method effectively yields bulk bodies of perovskite materials such as BaZrO3 at temperatures below 100 °C in atmospheric pressure.
