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Title: Templated synthesis of crystalline mesoporous CeO 2 with organosilane-containing polymers: balancing porosity, crystallinity and catalytic activity
Abstract We report the synthesis of ordered mesoporous ceria ( m CeO 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 °C. After the thermal engineering at 700 °C for 12 h ( m CeO 2 -700-12 h), m CeO 2 still has a specific surface area of 96 m 2 g −1 with a pore size of 14 nm. m CeO 2 is demonstrated to be active for electrochemical oxidation of sulfite. m CeO 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 m CeO 2 that has a lower crystallinity.  more » « less
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Materials Futures
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Medium: X
Sponsoring Org:
National Science Foundation
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