Oxide-supported single-atom Pt materials are prepared by combining surface organometallic chemisorption with atomic layer deposition (ALD). Here Pt is supported as a discrete monatomic "pincer" complex, stabilized by an atomic layer deposition (ALD) derived oxide overcoat, and then calcined at 400 °C under O 2 . ALD-derived Al 2 O 3 , TiO 2 , and ZnO overlayers are effective in suppressing Pt sintering and significantly stabilizing single Pt atoms. Furthermore, this procedure decreases the overall Pt nuclearity (∼1 nm average particle diameter) versus bare Pt (∼3.8 nm average diameter), as assayed by aberration corrected HAADF-STEM. The TiO 2 and ZnO overcoats are significantly more effective at stabilizing single-atom Pt species and decreasing the overall Pt nuclearity than Al 2 O 3 overcoats. Vibrational spectroscopy of adsorbed CO also shows that oxidized Pt species commonly thought to be single Pt atoms are inactive for catalytic oxidation of adsorbed CO. CO chemisorption measurements show site blockage by the ALD overcoats.

Porous CeWOx catalysts with impressive specific surface areas and deNOx activity were constructed by a rapid and solvent-free strategy.

A series of Fe/Beta@SBA‐15 core‐shell structural catalysts were designed and controllablly constructed by an ultradilute liquid‐phase coating method. Their catalytic activities were examined for ammonia selective catalytic reduction of NOx. It was found that their acidity and redox property were strongly dependent on SBA‐15 shells, Fe/Beta@SBA‐15 catalysts exhibit good propene and SO2 poisoning resistance, excellent hydrothermal stability, and wide NOx conversion temperature range (325–600°C) under a high gas hour space velocity. The kinetics results indicate that the mesoporous structure of SBA‐15 shell lowers the diffusion limitation and promotes the reactants accessing to active sites. Moreover, TGA and in situ DRIFT results reveal that SBA‐15 shell can not only prevent the generation and deposition of coke and nitrate species from blocking active sites but also serve as an effective “obstacle” to inhibit active FeOx nanoparticles from agglomerating at high temperature, leading to the higher propene resistance than Fe/Beta. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3967–3978, 2018

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