Highly n-Type Titanium Oxide as an Electronically Active Support for Platinum in the Catalytic Oxidation of Carbon Monoxide

作者：Baker L Robert; Hervier Antoine; Seo Hyungtak; Kennedy Griffin; Komvopoulos Kyriakos; Somorjai Gabor A^*

来源：Journal of Physical Chemistry C, 2011, 115(32): 16006-16011.

DOI：10.1021/jp203151y

The role of the oxide-metal interface in determining the activity and selectivity of chemical reactions catalyzed by metal particles on an oxide support is an important topic in science and industry. A proposed mechanism for this strong metal-support interaction is electronic activation of surface adsorbates by charge carriers. Motivated by the goal of using electronic activation to drive non thermal chemistry, we investigated the ability of the oxide support to mediate charge transfer. We report an approximately 2-fold increase in the turnover rate of catalytic carbon monoxide oxidation on platinum nanoparticles supported on stoichiometric titanium dioxide (TiO(2)) when the TiO(2) is made highly n-type by fluorine (F) doping. However, for nonstoichiometric titanium oxide (TiO(x < 2)) the effect of F on the turnover rate is negligible. Studies of the titanium oxide electronic structure show that the energy of free electrons in the oxide determines the rate of reaction. These results suggest that highly n-type TiO(2) electronically activates adsorbed oxygen (O) by electron spillover to form an active O(-) intermediate.

• 出版日期2011-8-18