Sintering and electronic conducting properties of La_0.7 Ca_0.3 CrO₃ perovskite synthesized by a glycine-nitrate process

Abstract

La_0.7 Ca_0.3 CrO₃ powder consisting of superfine and uniform particles (100-200 nm) were synthesized using a glycine-nitrate process (GNP). The sintering and electronic conducting properties of La_0.7 Ca_0.3 CrO₃ were investigated in the sintering temperature range of 1 200–1450 °C. The desired morphology of the powder significantly improved its sinterability. La_0.7 Ca_0.3 CrO₃ ceramics sintered at 1 250–1450 °C show high relative densities above 95%. The ceramics sintered at 1 250–1400 °C have very similar electronic conducting properties, providing electronic conductivities around 55 Ω⁻¹ cm⁻¹ at a measuring temperature of 800 °C. Further increasing the sintering temperature to 1450 °C led to an apparent degradation of electronic conducting properties. This research demonstrates the advantage of the GNP in producing La_0.7 Ca_0.3 CrO₃ with respect to the enhanced sintering properties and superior electronic conducting properties.

Keywords

sintering / glycine-nitrate process / electrical conductivity / perovskites

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