Low temperature synthesis of spherical lanthanum aluminate nanoparticles

Abstract

Lanthanum aluminate powders could be prepared by a novel ultrasonic assisted combined gel synthesis from metal chloride solutions with ammonia destabilization. The decomposition and crystallization behavior of the gel was studied by DTA/TGA. The washed and powdered gel was calcined at different temperatures and the phase evolution was studies by X-ray diffractometry. Phase pure lanthanum aluminate was obtained for powders calcined at a temperature as low as 600 °C for 4 h. NMR studies confirmed that the Al in the powders were octahedrally coordinated. SEM study revealed that the powders were uniformly distributed with occasional primary agglomerates. TEM micrographs show that the powders were spherical nanoparticles with sizes in the range of 25–40 nm.