Texture stability of mesoporous ceria made from nanoparticles assembly

摘要

A supramolecular templating approach to crystalline ceria mesoporous materials had been developed, using inorganic colloidal CeO_2 nanoparticles as building blocks and HF or HC1 as binding reagent. Calcination of the supramolecular-templated mesostructures yielded mesoporous ceria materials with high surface areas. The density of the surface hydroxyls was affected by the assembly process adopted as detected by D_2-OH exchange. Structural changes under various treatment conditions were investigated in order to assess the thermal or hydrothermal stability of the obtained materials. The mesoporous ceria with HF as binding reagent exhibited an exceptionally high thermal and hydrothermal stability, which was attributed to the combination of large wall thickness and the surface fluoride ions. The surface F ions prevented the meso-ceria from sintering of nanoparticles.