We made precipitated nano-ceria(~5 nm) on the surface of the catalyst by heat treatment of Cesupersaturated amorphous CeTiOxto improve the oxygen storage properties of CeO_2. The catalysts were prepared by sol-gel met...We made precipitated nano-ceria(~5 nm) on the surface of the catalyst by heat treatment of Cesupersaturated amorphous CeTiOxto improve the oxygen storage properties of CeO_2. The catalysts were prepared by sol-gel methods and TiO_2 nanoparticles were preferentially generated as a core material to form selective Ce-supersaturated structure on the catalyst surface. Reaction temperature and amount of doping element are optimized to induce selective crystallization of CeO_2. Cee Ce(2 nd shell)bond around 0.38 nm of Ce L3-edge extended X-ray absorption fine structure is reduced and nanostructure of precipitated ceria on the surface is observed by HREM. The catalyst is present as amorphous with precipitated nano-CeO_2 on the surface. The de-NOxefficiency of the catalyst, which has precipitated CeO_2, improves by ~50% owing to the simultaneous reactions of the nano CeO_2 and the amorphous CeTiO_x.展开更多
基金Project supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)through GCRC-SOP(2011-0030013)
文摘We made precipitated nano-ceria(~5 nm) on the surface of the catalyst by heat treatment of Cesupersaturated amorphous CeTiOxto improve the oxygen storage properties of CeO_2. The catalysts were prepared by sol-gel methods and TiO_2 nanoparticles were preferentially generated as a core material to form selective Ce-supersaturated structure on the catalyst surface. Reaction temperature and amount of doping element are optimized to induce selective crystallization of CeO_2. Cee Ce(2 nd shell)bond around 0.38 nm of Ce L3-edge extended X-ray absorption fine structure is reduced and nanostructure of precipitated ceria on the surface is observed by HREM. The catalyst is present as amorphous with precipitated nano-CeO_2 on the surface. The de-NOxefficiency of the catalyst, which has precipitated CeO_2, improves by ~50% owing to the simultaneous reactions of the nano CeO_2 and the amorphous CeTiO_x.
