Core@shell bimetallic nanoparticle synthesis via anion coordination.

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.