Metal Ion Substitution Effect and Component Regulation of Perovskite-Type La1-xCaxCrO3 Nanomaterials

Perovskite-type La1-xCaxCrO3 nanostructures were synthesized by a combustion method and the crystalline structures, sinterability, electrical properties and thermal expansion of the materials was studied with different Ca2+ substitution. It was found that the introduction of Ca2+ reduced structural stability of La1-xCaxCrO3, especially a high degree of substitution, even though enhanced sintering of the ceramics and simultaneously increased the electronic conductivity and optimizing the thermal expansion of the materials. In view of the structural stability, sinterability, electrical properties and thermal expansion, the preferred Ca2+ substitution was ascertained to be x = 0.2, at which the sample not only obtains a relatively stable perovskite-type structure and adequate density, but also attains higher electrical conductivity of 53.6 S . cm(-1) and a compatible thermal expansion coefficient (TEC) of 10.7 x 10(-6) K-1 at 800 degrees C.