Morphology-dependent properties and adsorption performance of CeO2 for fluoride removal

Three kinds of CeO2 materials with different morphologies (nanorods, octahedron and nanocube) were prepared by simple hydrothermal method. Adsorption behaviors of fluoride onto the three CeO2 materials were investigated. Three CeO2 materials exhibited different adsorption performance for fluoride. The CeO2 nanorods mainly exposed {1 0 0} and {1 1 0} planes had the highest adsorption capacity for fluoride, whereas the CeO2 nanocubes with {1 0 0} planes exposed showed the lowest adsorption capacity. Characterization results showed that the three CeO2 materials with different morphologies showed different physical and chemical properties, which may result in big difference in their removal mechanism for fluoride, and thus displayed different adsorption performances for fluoride removal. The removal mechanism of fluoride on the three CeO2 mainly included Ce3+-O defect, ion exchange, surface adsorption and pore filling.