Lonely atoms with special gifts: breaking linear scaling relationships in heterogeneous catalysis with single-atom alloys. Selective hydrogenation of 1,3-butadiene on platinum-copper alloys at the single-atom limit. Self-hydrogenated shell promoting photocatalytic H 2 evolution on anatase TiO 2. Increasing solar absorption for photocatalysis with black hydrogenated titanium dioxide nanocrystals. Surface chemistry of Au/TiO 2: thermally and photolytically activated reactions. Titania supported gold nanoparticles as photocatalyst. Promotion of atomic hydrogen recombination as an alternative to electron trapping for the role of metals in the photocatalytic production of H2.
Hydrogen spillover and its relation to hydrogenation: observations on structurally defined single-atom sites. Catalyst support effects on hydrogen spillover. This study provides a quantitative assessment of how hydroxyl surface chemistry impacts spillover thermodynamics, and contributes to the general understanding of spillover phenomena. Increased H* adsorption correlates with the associated changes in titania surface zwitterion concentration. Second, the number of spillover sites increases with temperature, due to increasing hydroxyl acid–base equilibrium constants. First, entropically favourable adsorption results from high proton mobility and configurational surface entropy.
This unexpected adsorption behaviour has two origins. In stark contrast to traditional gas adsorption systems, H* adsorption increases with temperature. The spillover species (H*) is best described as a loosely coupled proton/electron pair distributed across the titania surface hydroxyls. Here we measure weak, reversible H 2 adsorption on Au/TiO 2 catalysts, and extract the surface concentration of spilled-over hydrogen. While well documented, H spillover is poorly understood and largely unquantified. Hydrogen spillover involves the migration of H atom equivalents from metal nanoparticles to a support.
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