Importance

Loading Importance Indicators...

Abstract

Proton conductive material comprising a compound of a monoclinic crystal structure which is in a reversibly reduced state from a compound of a similar monoclinic crystal structure represented by the general formula: Na.sub.x Al.sub.y Ti.sup.3+.sub.x-y Ti.sup.4+.sub.8-x O.sub.16, in which 1.5.ltoreq.x.ltoreq.2, 1.5.ltoreq.y.ltoreq.2, x.gtoreq.y. The compund of a monoclinic crystal structure, represented by the general formula: Na.sub.x Al.sub.y Ti.sup.3+.sub.x-y Ti.sup.4+.sub.8-x O.sub.16 is changed reversibly to a compound of a monoclinic crystal structure in a reduced state by a reducing treatment at a temperature within a range from 600.degree..degree.C. to 1000.degree. C. Such a compound of a monoclinic crystal structure which is in a reduced state is changed reversibly back to the compound of a monoclinic crystal structure, represented by the general formula: Na.sub.x Al.sub.y Ti.sup.3+.sub.x-y Ti.sup.4+.sub.8-x O.sub.16 by applying heat treatment in air at a temperature within a range from 1200.degree. C. to 1300.degree. C. A method of producing such proton conductive material comprises the steps of mixing starting alumina material, starting titania material and a sodium salt, sintering at a temperature within a range from 1000.degree. C. to 1300.degree. C. and then applying a reducing treatment in a hydrogen atmosphere at a temperature within a range from 600.degree. C. to 1000.degree. C.

Loading the Abstract Image...

First Claim