Facile fabrication of nanoparticles in the nanospace of ultrathin TiO ₂-gel films: Composition, morphology and catalytic activity

In this article, we present in-situ synthesis of nanoparticles of various compositions and morphologies in the nanospace of ultrathin TiO₂-gel films using low temperature H₂ and O₂ plasmas as reductant and oxidant, respectively. Parameters that influence the formation of nanoparticles were investigated and discussed. Reversible chemical transformation was found to give monodisperse nanoparticles. Catalytic activities of Pd monometallic and Ag-core/Pd-shell bimetallic nanoparticles were tested for hydrogenation of methyl acrylate. The much enhanced catalytic activity is attributed mainly to a large ratio of the surface Pd atoms.