Researchers in New Zealand have designed a new synthesis process, which combines the advantages of low-depth low-concentration ion implantation and high-temperature electron beam annealing to produce surface metallic nanoclusters on silica. The method uses an electron beam to induce the selective desorption of molecules at the surface of the silica matrix. This reduces the silica surface level while the nanoclusters coalesce into bigger structures and result in bare nanoclusters on the surface. Surprisingly, the nanoparticles are not significantly oxidized when in contact with air.
http://nanotechweb.org/cws/article/lab/45389