文摘
Ceria-alumina particles of a wide variety of structures, from micrometer-sized hollow spheres to nanoparticles,were produced from aerosols of different natures, but all derived from nitrate salts passed through a low power (<1000W) atmospheric pressure plasma torch. The amount of water present with the nitrate salts was found to significantlyaffect the morphology of the resulting material. A model was proposed that explains the mechanism in which wateracts as a blowing agent to create hollow metal oxide spheres that then shatter to form metal oxide nanoparticles. Furtherexamination of the nanoparticles revealed that they display a core/shell morphology in which the core material iscrystalline CeO2 and the shell material is amorphous Al2O3. These unique core/shell materials are interesting candidatesfor catalyst support materials with high thermal durability. In addition, experiments have shown that the nanoparticlescan be readily converted into CeAlO3 perovskite.