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Atomic carbon on Co(0001), deposited by ethylene decomposition, forms islands with a (√3 × √3)R30°structure at low C coverage (∼0.2 ML), whereas a high C coverage (0.5 ML, saturation) induces a reconstruction of the cobalt surface. Atomic carbon weakens the adsorption of CO and H 2 , but even a saturated atomic carbon layer does not block the surface for adsorption. Carbon−carbon coupling, i.e., polymeric carbon formation, was not observed for temperatures ≤630 K on the close-packed cobalt surface. Polymeric carbon, in the form of small graphene islands, forms on the close-packed terraces after heating of an acetylene-saturated surface. Graphene also forms upon heating of an atomic carbon covered surface on which ethylene was dosed at low temperature. In this case, step edges act as a nucleation point of the graphene islands, while their growth proceeds via the addition of C 2 H x species. In both cases, hydrogenated forms of carbon rather than atomic carbon are key precursors for graphene growth. Graphene covers the cobalt surface, thereby inhibiting adsorption of CO and hydrogen completely. The described graphene formation mechanism is seen as a relevant, low temperature route to detrimental carbon that would deactivate a cobalt FT catalyst. Atomic carbon is more reactive than graphene, as it is oxidized at lower temperatures than graphene. The graphene islands formed at relatively low temperatures are of poor structural quality and contain (islands of) encapsulated cobalt atoms.

Recently there has been a renewed interest in Co-catalyzed Fischer−Tropsch synthesis (FTS) from natural gas, coal, and biomass, because it offers a realistic alternative to crude oil as a source of transportation fuels. Efforts to understand the FT mechanism on the atomic level have mainly focused on theoretical methods, whereas experimental surface science results have only had little impact on the understanding of the mechanism. An essential step in any FT mechanism is scission of the C−O bond. On a flat Co(0001) surface direct dissociation of the CO molecule is practically impossible at FTS conditions. We have found for the first time experimentally that the C−O bond can be broken at 350 K even on the relatively inert Co(0001) surface if a C x H y group and a hydrogen atom are attached to the C-end of the C−O moiety.

Enhanced productivity toward propene oxide in the direct propene epoxidation with hydrogen and oxygen over gold nanoparticles supported on titanium‐grafted silica was achieved by adjusting the gold–titanium synergy. Highly isolated titanium sites were obtained by lowering the titanium loading grafted on silica. The tetrahedrally coordinated titanium sites were found to be favorable for attaining small gold nanoparticles and thus a high dispersion of gold. The improved productivity of propene oxide can be attributed to the increased amount of the interfacial AuTi sites. The active hydroperoxy intermediate is competitively consumed by epoxidation and hydrogenation at the AuTi interface. A higher propene concentration is favorable for a lower water formation rate and a higher formation rate of propene oxide. Propene hydrogenation, if occurring, can be switched off by a small amount of carbon monoxide.

A nanoporous smectic liquid crystalline polymer network has been exploited to fabricate photo patternable organic-inorganic hybrid materials, wherein, the nanoporous channels control the diameter and orientational order of the silver nanoparticles.

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The addition of Re to Ni on TiO yields efficient catalysts for the hydrogenation of acids and esters to alcohols under mild conditions. Rhenium promotes the formation of atomically dispersed and sub-nanometre-sized bimetallic species interacting strongly with the oxide support.

Water electrolysis to form hydrogen as a solar fuel requires highly effective catalysts. In this work, theoretical and experimental studies are performed on the activity and stability of Ni−Mo cathodes for this reaction. Density functional theory studies show various Ni−Mo facets to be active for the hydrogen evolution reaction, Ni segregation to be thermodynamically favorable, and Mo vacancy formation to be favorable even without an applied potential. Electrolyte effects on the long‐term stability of Ni−Mo cathodes are determined. Ni−Mo is compared before and after up to 100 h of continuous operation. It is shown that Ni−Mo is unstable in alkaline media, owing to Mo leaching in the form of MoO42−, ultimately leading to a decrease in absolute overpotential. It is found that the electrolyte, the alkali cations, and the pH all influence Mo leaching. Changing the cation in the electrolyte from Li to Na to K influences the surface segregation of Mo and pushes the reaction towards Mo dissolution. Decreasing the pH decreases the OH− concentration and in this manner inhibits Mo leaching. Of the electrolytes studied, in terms of stability, the best to use is LiOH at pH 13. Thus, a mechanism for Mo leaching is presented alongside ways to influence the stability and make the Ni−Mo material more viable for renewable energy storage in chemical bonds.