High active platinum clusters on titanium dioxide supports toward carbon monoxide oxidation

Highly dispersed single metal atom or cluster catalysts have attracted increasing attention because of improved atomic efficiency, higher reactivity and better selectivity. However, these catalysts on oxide supports often sinter to form large particles at high temperatures, which can lead to reduced surface areas and decreased catalytic activities, and are a major challenge to the development of optimal low temperature-active and sinter-resistant catalysts. Two kinds of platinum (Pt) clusters on titanium dioxide (TiO2) supports are successfully prepared in this study to investigate the low temperature activity towards carbon monoxide (CO) oxidation as well as thermal stability of the resulting catalyst; highly oxidized Pt clusters demonstrated higher catalytic activity and thermal stability towards CO oxidation as compared with lower oxidized Pt clusters, since the high oxidation state of the catalytic metal active sites is believed to be highly correlated with the electronic metal-support interactions (EMSI) between Pt and TiO2 support, and the results suggest that EMSI tailors the unoccupied 5d state of Pt species, thus greatly leading to the high activity and thermal stability.