Systematic study on novel catalytic activity of CO oxidation driven by strong electronic interaction between the monatomic-layered Pt30 cluster disk and the Si substrate.

Abstract

Catalytic activity of thermal CO oxidation was studied for monatomic-layered platinum cluster disks, Pt30, bonded to the (111) surface of a silicon substrate. Temperature-programmed desorption (TPD) measurements were repeated for a given cluster sample with a systematic change in the reactant amounts supplied, and the peaks observed in the TPD spectra were deconvoluted so as to obtain probabilities of individual reactions. It was concluded that this system possesses an ability of low-temperature reductive activation of oxygen molecules, which is one of the critical steps in the CO oxidation. This high performance is explained in terms of negative charges accumulated at a sub-nano interface between the cluster disk and the silicon substrate surface as a result of their strong electronic interaction.