Patent ID: 7670585

Claim:
A method for preparing an electroconductive compound, which comprises a step of subjecting a precursor to heat treatment, wherein the precursor contains CaO and/or SrO, and Al 2 O 3 , the molar ratio of a total of CaO and SrO:Al 2 O 3 is from 12.6:6.4 to 11.7:7.3 as calculated as oxides, the total content of CaO, SrO and Al 2 O 3 in the precursor is at least 50 mol %, and the precursor is a vitreous or crystalline material; and wherein the heat treatment is carried out by holding a mixture of the precursor and a reducing agent at 600-1,415° C. in an inert gas or vacuum atmosphere with an oxygen partial pressure of at most 10 Pa, where the reducing agent is selected from the group consisting of a metal, an intermetallic compound and a metallic compound.