We showed that alumina (Al(2)O(3)) overcoating of supported metal nanoparticles (NPs) effectively reduced deactivation by coking and sintering in high-temperature applications of heterogeneous catalysts. We overcoated palladium NPs with 45 layers of alumina through an atomic layer deposition (ALD) process that alternated exposures of the catalysts to trimethylaluminum and water at 200°C. When these catalysts were used for 1 hour in oxidative dehydrogenation of ethane to ethylene at 650°C, they were found by thermogravimetric analysis to contain less than 6% of the coke formed on the uncoated catalysts.
View Article and Find Full Text PDF(18)O isotope labelling studies of the CO oxidation-assisted epoxidation of propene, catalyzed by a mixture of Au/TiO(2) and TS-1, using a methanol-H(2)O solvent showed the O in the epoxide was exclusively from O(2) and not H(2)O or methanol.
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