Hydrothermal synthesis and sintering of lanthanum chromite powders doped with calcium

Precursor La–Ca gels of LaCrO3, La0.9Ca0.1CrO3 and La0.8Ca0.2CrO3 were prepared by coprecipitation and then crystallized under hydrothermal conditions. Under these conditions, mono dispersed nanosized (<300 nm) powders of LaCrO3 and its solid solutions doped with calcium were obtained at temperatures between 350 and 425 °C. The powders were sintered in air at a temperature range of 1200–1500 °C for intervals between 1 and 5 h. A maximum apparent density of 97.66% was preferentially achieved by pellets with the larger amount of Ca, La0.8Ca0.2CrO3, sintered at 1400 °C for 5 h in air atmosphere. The average grain size measured on sintered specimens was of 6 μm.