Preparation, Characterization and Photocatalysis Properties of Ultrafine Perovskite-Type LaCoO₃

Abstract:

Using La₂O₃ and Co(NO₃)₂•6H₂O as raw material, ultrafine perovskite-type oxides LaCoO₃ was prepared by Supercritical Fluid Drying Technology and Sol-Gel method. The prepared materials’ crystal structure and morphology were characterized by TG-DTA、XRD、FT-IR and TEM. The photocatalytic activity of ultrafine LaCoO₃ powders was evaluated by degradation of methyl orange (MO) solution under 15W UV light irradiation. The results show: At 250°C , the amorphous ultrafine La-Co particles with the size less than 10 nm can be obtained by Supercritical Fluid Drying Technology. At 850°C , the size of the particles increased to 15-35nm, the nanocrystalline LaCoO₃ had a perfect rhombohedral perovskite structure. At 900°C , the crystalline phases of the lanthanum-cobalt mixed oxides were LaCoO₃ and La₂O₃, and the amorphous component is Co₂O₃, the presence of lanthanum affects the crystallization of cobalt oxides. The LaCoO₃ has excellent photocatalytic activities and 100% MO solution was decolorized only after 4h.

• Periodical: Advanced Materials Research (Volumes 197-198)
• Pages: 935-942
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.197-198.935
• Online since: February 2011
• Authors: Xia Fu, Yang Chen, Gao Qi Yu, Chao Yu, Hou Zhi Wang, Guang De Zhang
• Keywords: LaCoO₃, Photocatalytic, Sol-Gel (SG), Supercritical Fluid Drying, Ultrafine

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