Templated synthesis of crystalline mesoporous CeO_(2) with organosilane-containing polymers: balancing porosity, crystallinity and catalytic activity

摘要

We report the synthesis of ordered mesoporous ceria(mCeO_(2))with highly crystallinity and thermal stability using hybrid polymer templates consisting of organosilanes.Those organosilane-containing polymers can convert into silica-like nanostructures that further serve as thermally stable and mechanically strong templates to prevent the collapse of mesoporous frameworks during thermal-induced crystallization.Using a simple evaporation-induced self-assembly process,control of the interaction between templates and metal precursors allows the co-self-assembly of polymer micelles and Ce^(3+)ions to form uniform porous structures.The porosity is well-retained after calcination up to 900℃.After the thermal engineering at 700℃ for 12 h(mCeO_(2)-700-12 h),mCeO_(2) still has a specific surface area of 96 m^(2) g^(−1) with a pore size of 14 nm.mCeO_(2) is demonstrated to be active for electrochemical oxidation of sulfite.mCeO_(2)-700-12 h with a perfect balance of crystallinity and porosity shows the fastest intrinsic activity that is about 84 times more active than bulk CeO_(2) and 5 times more active than mCeO_(2) that has a lower crystallinity.