(617gs) Sputter Deposition of Silver-Copper Nanoparticles for the Oxygen Reduction Reaction

The co-sputtering of bimetallic nanoparticles opens up exciting new directions in the field of heterogeneous catalysis. In addition to precise control over nanoparticle size, composition, and loading, this vapor phase deposition technique could allow for the â??freezing-inâ? of phases which are not thermodynamically stable in the bulk and which may have interesting properties beyond those of their parent materials. These nanoparticulate alloy phases are of interest to researchers in heterogenous catalysis, as they allow for more precisely tuned adsorbate binding energies than are offered by bulk phase materials. Alloying copper into silver nanoparticles, for example, has been predicted to enhance silverâ??s activity for the electrochemical oxygen reduction reaction (ORR). Here we demonstrate the ability to deposit size selected silver-copper nanoparticles from 5 to 20 nm across a full range of silver-copper compositions, and we show an enhancement in catalytic activity of the bimetallic nanoparticles for the ORR in base compared to pure silver.