ELECTROCONDUCTIVE 12CaO.7Al sb 2 /sb O sb 3 /sb AND COMPOUND OF SAME TYPE, AND METHOD FOR PREPARATION THEREOF

摘要

In a solid solution system of Al 2 O 3 and CAO or SrO, it has been difficult to obtain a material having a high electrical conductivity (>10 -4 S·cm - ) at room temperature. A compound is provided in which electrons at a high concentration are introduced into a 12CaO·7Al 2 O 3 compound, a 12SrO·7Al 2 O 3 compound, or a mixed crystal compound containing 12CaO·7Al 2 O 3 and 12SrO·7Al 2 O 3 . The compound formed by substituting all the free oxygen ions with electrons is regarded as an electride compound in which [Ca 24 Al 28 O 64 ] 4+ (4e - ) or [Sr 24 Al 28 O 64 ] 4+ (4e - ) serves as a cation and electrons serve as anions. When a single crystal or a hydrostatic pressure press molded material of a fine powder thereof is held at approximately 700°C in an alkaline metal vapor or an alkaline earth metal vapor, melt of a hydrostatic pressure press molded material of a powder is held at approximately 1,600°C in a carbon crucible, followed by slow cooling for solidification, or a thin film of the compound held at approximately 600°C is implanted with rare gas ions, a great number of the free oxygen ions can be substituted with electrons.