Mesoporous Cu‐Ce‐O_x Solid Solutions from Spray Pyrolysis for Superior Low‐Temperature CO Oxidation

Abstract

Developmento fP tg roup metal-free catalysts for low-temperature CO oxidationr emains critical. In this work, active and stable mesoporous Cu-Ce-O x solid solutions are prepared by using spray pyrolysis. The specific surface areas and pore volumes reach as high as 170 m 2 g À1 and 0.24 cm 3 g À1 ,r espectively.T he results of CO oxidation study suggest that (1) the catalysto btained by spray pyrolysis possesses much higher activity than those made by co-precipitation, sol-gel,a nd hydrothermalm ethods;( 2) the optimal Cu 0.2 -Ce 0.8 -O x solid solution presents ar eactivity over 28 times that of both single-component CuO and CeO 2 at 70 8C. Based on the study of pure-phase Cu-Ce-O x solid solutions by selectivel eaching of segregatedC uO x species, the active center for CO oxidationi sc onfirmed as the bimetallic Cu-Ce-O site, whereas the individual CuO x particles not only act as spectators but also block the active Cu-Ce-O sites. A low apparent activation energy of approximately 48 kJ mol À1 is detected for CO oxidation at the Cu-Ce-O site, making Cu-Ce-O x solid solutionsa ble to present high activity at low temperature. Furthermore, the Cu-Ce-O x catalysts exhibit excellent stabilitya nd thermal tolerance towardC Oo xidation.Scheme1.The illustration of strategy and processesfor obtainingp urephasem esoporous Cu-Ce-O x solid solution for CO oxidation.

Titania supported synergistic palladium single atoms and nanoparticles for room temperature ketone and aldehydes hydrogenation

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Hybrid chemoenzymatic heterogeneous catalyst prepared in one step from zeolite nanocrystals and enzyme–polyelectrolyte complexes

“…On the rst hand, aerosol processing is well suited for the preparation of many types of inorganic heterogeneous catalysts. [39][40][41][42][43][44][45][46][47] In fact, aerosol methods were already demonstrated to be successful and scalable to form TS-1 microspheres with a hierarchical porosity. 48 On the second hand, spray drying is also widely used to dry proteins for food and pharmaceutical applications.…”

Recent progress in use and observation of surface hydrogen migration over metal oxides

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