TiO2 catalysis

The Genesis and Principle of Catalysis at Oxide Surfaces Surface-Mediated Dynamic Aspects of Catalytic Dehydration and Dehydrogenation on TiO2(110) by STM and DFT 317... 

Fig. 2. Structure of the unreconstructed TiO2(001) surface. Black and grey spheres are Ti and O atoms, respectively. H. Idriss and M.A. Barteau, Advances in Catalysis, v. 45 (2000). Reproduced by permission of Academic Press.

The most common reaction at the anodic side of biofuel cells is the oxidation of sugars which relies on the catalytic properties of oxidases. This class of enzymes has, however, usually poor potential for direct ET. Direct ET on the anodic site was, however, described for a number of hydrogenases [235, 236] and cellobiose dehydrogenase [225, 237, 238]. Enzymatic catalysis by means of direct ET was also realized on conducting graphite or TiO2 particles [239, 240]. 

As it appears from the scheme, this process is stoichiometric in light, well different from the above mentioned chain processes. The use of the term photocatalyst in this meaning is not common, since this term is rather referred to the oxidation and mineralization of organic pollutants caused by irradiation in the presence of semiconductor (e.g. TiO2, ZnS, CdS) powders. However, the mechanism in Scheme 4 seems strictly analogous to the usual concept of catalysis, with the additional requirement of photo activation and thus joining the two words and defining the process as photocatalytic seems to us natural, as illustrated in a recent review. ... 

E. Vogt, A. van Dillen, J. Geus and F. Janssen, "Selective Catalytic Reduction of NOx with NH3 over a V205/TiO2 on Silica Catalyst", Catalysis Today. 1988,2.569-579. 

CONTROLLING FACTORS IN HETEROGENOUS CATALYSIS AND THE MESOSCALES IN MESOPOROUS TIO2... 

F ure 9.17 Amount of Hj produced by the WGS reaction on catalysts generated by depositing 0.15 ML of Au, Cu, or Pt on CeOyTiO2(110) surfaces in which 12-14% of the titania was pre-covered with CeO nanoparticles. For comparison, we also include data for the deposition of the metals on TiO2(110). The reported values for the production of H2 were obtained after exposing the catalysis to 20 torr of CO and 10 torr of HjO at 625 K for 5 min. The number of H2 molecules produced is normalized by the sample surface area. Copyright 2010 the American Chemical Society. 

Chretien S, Metiu H Density functional study of the CO oxidation on a doped rutile TiO2(110) effect of ionic Au in catalysis, Catal Lett 107 (3-4) 143-147, 2006. 

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