Formation, sintering, and electrical conductivity of (Nd1−xCax)CrO3 (0≤x≤0.25) using citric acid as a gelling agent

In Ca2+-substituted NdCrO3, single-phase perovskite compounds (Nd1−xCax)CrO3, where x=0–0.25, have been formed by a citric acid processing. (Nd1−xCax)CrO3 powders consisting of submicrometer-size particles are sinterable; dense materials can be fabricated by sintering for 2 h at 1700°C under atmospheric pressure. The relative densities, grain sizes, and electrical conductivities increase with increased Ca2+ content. (Nd0.75Ca0.25)CrO3 materials show an excellent electrical conductivity of 1.9×10 S m−1 at 1000°C.