| 摘要 |
<p>A first C12A7 compound which includes an OH- ion, an On- ion radical and the like in a concentration of 2 X 1019 cm-3 or less; and a method for preparing the first C12A7 compound which comprises subjecting a mixed material containing Ca and Al to a solid phase reaction at a firing temperature not lower than 1200˚C and lower than 1449˚C in a dry oxygen atmosphere having an oxygen partial pressure of 0.1 atm or more and a steam partial pressure of 10-3 atm or less, keeping the resultant product at a temperature of 1200˚C or higher and then cooling rapidly. A second C12A7 compound which includes an OH- ion in a concentration of 2 X 1019 cm-3 or less and an On- in a high concentration of more than 2 X 1019 cm-3; and a method for preparing the second C12A7 compound which comprises subjecting the first C12A7 compound to a heat treatment. The second C12A7 compound is capable of reversibly including or releasing an On- ion radical through the elevation or lowering of the temperature thereof in a temperature region of 300 to 850˚C. The above C12A7 compounds may include an X- ion such as an active oxygen radical selectively and reversibly with improved controllability, and thus are useful for an oxidation catalyst, an anti-bacterial agent, an ion conducting material, an electrode for a solid electrolyte fuel cell, and the like.</p> |
