Core@shell structured bimetallic nanoparticles are currently of immense interest due to their unique electronic, optical and catalytic properties. However, their synthesis is non-trivial. We report a new supramolecular route for the synthesis of core@shell nanoparticles, based on an anion coordination protocol--the first to function by binding the shell metal to the surface of the pre-formed primary metal core before reduction. The resultant gold/palladium and platinum/palladium core@shell nanoparticles have been characterized by aberration-corrected scanning transmission electron microscopy (as well as other techniques), giving striking atomic-resolution images of the core@shell architecture, and the unique catalytic properties of the structured nanoparticles have been demonstrated in a remarkable improvement of the selective production of industrially valuable chloroaniline from chloronitrobenzene.

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Au/CeZrO 4 catalysts have shown very low temperature activity for the WGS reaction. Characterisation of the as-prepared catalysts shows Au is present primarily as isolated Au 3+ atoms. It has been found that a higher proportion of Au 3+ present in the as-prepared catalyst leads to a higher WGS activity, although under reaction conditions reduction to Au 0 is observed. Use of TPR and iso-thermal H 2 O re-oxidation has shown that Au reacts with H 2 O at lower temperatures than an equivalent Pt/CeZrO 4 catalyst, indicating that H 2 O activation is key in the onset of low temperature WGS activity.

Picture perfect: Information about the local topologies of active sites on commercial nanoparticles can be gained with atomic resolution through spherical‐aberration‐corrected transmission electron microscopy (TEM). A powder of Pt nanoparticles on carbon black was examined with two advanced TEM techniques based on recent developments in hardware (aberration correction) and computation (exit wavefunction restoration).

Significant effects on catalytic activity in the epoxidation of cyclohexene with alkyl hydroperoxides are observed when the surface of mesoporous silica (MCM-41) is modified with either Ge(IV) or Sn(IV) prior to the grafting of tetracoordinated Ti(IV). Titanium centers attached via oxygen to two silicons and one germanium show an increase in turnover frequency of up to 140% compared to centers attached via three Si−O bonds to a purely siliceous MCM-41. The tin-modified catalyst, in contrast, shows poor activity. The environments of the Ti, Ge, and Sn centers were probed directly by in situ X-ray absorption spectroscopy and also by ex situ transmission electron microscopy. The germanium-modified silica contains evenly distributed, anchored tetrahedral Ge(IV) species, whereas the tin-containing material forms extraframework particles of SnO2.