Solid electrolyte, method of producing same and fuel cell using same

摘要

A solid electrolyte used in a cell and represented by the following formula:
€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ La (1-x-y) Ln x A y Ga (1-z) B z O 3-0.5(x+y+z)
where Ln is at least one element selected from the group consisting of Gd, Sm and Nd; A is Ba; B is Mg; x is 0.1;y is 0.1; and z is 0.2, wherein the solid electrolyte is formed of particles whose means diameter is within a range of from 4 to 10 µm, the solid electrolyte being produced by a method comprising: (a) mixing lanthanum oxide, gallium oxide, oxide of at least one rate earth element selected from the group consisting of Gd, Sm and Nd, barium oxide and magnesium oxide to form a mixture; (b) firing the mixture in air at a temperature ranging from 1100 to 1200 °C for a time ranging from 2 to 8 hours to accomplish synthesizing a compound material; (c) pulverizing the compound material; (d) compacting the pulverized compound material; (e) adjusting mean diameter of the pulverized compound material within a range of from 0.5 to 0.8 µm; and (f) sintering the compacting compound material in air at a temperature ranging from 1400 to 1500 °C for a time ranging from 2 to 8 hours to form the solid electrolyte.