TiO2 , stoichiometric

We have previously demonstrated the stoichiometric cyclotrimerization of a variety of alkynes on reduced TiO2(001) surfaces in UHV using TPD [1,2]. A... 

Okazawa T, Kohyama M, Kido Y. 2006. Electronic properties of Au nano-particles supported on stoichiometric and reduced TiO2(110) substrates. Surf Sci 600 4430-4437. 

Fig. 9 Electron transfer per bond A as a function of the difference SV ad in the Madelung potentials (in Hartree per electron) acting on the Ti and O in neutral stoichiometric clusters (filled circles), in bulk rutile Ti02 (plus), and on the TiO2(110) surface (diamonds) (from Ref. 243).

The local geometry of the K adsorption site in TiO2(100)c(2x2)K has been probed using K -edge SEXAFS [106]. To form the c(2x2) overlayer 0.5 ML of K was deposited onto a stoichiometric TiO2(100)lxl surface, cleaned as described above. SEXAFS measurements were performed at normal and... 

The formation of formaldehyde from formic acid is not expected to occur on stoichiometric TiO2(110) because the surface cations are exclusively five-coordinate, and formaldehyde formation in the absence of reduced surface sites has been shown to be dependent on the presence of low-coordinate metal cations on titanium dioxide surfaces. Iwasawa et al. noted the absence of formaldehyde from the product slate of formic acid reaction products in their studies on the TiO2(110) surface [43]. 

Recently ALISS experiments and simple classical theory have been used to directly get the surface structure of TiO2(110) [41]. Figure 20 shows an unrelaxed stoichiometric Ti02 surface with bridging oxygen rows. 

Figure 35 STM image (14 x 14nm ) of a stoichiometric 1x1 rutile TiO2(H0) surface. Dark rows on the terraces correspond to bridging oxygen rows, while the bright rows are due to titanium rows. The inset shows a ball-and-stick model of the rutile TiO2(H0)-(l x 1) surface. Large balls represent oxygen atoms, and small balls represent titanium atoms. (From Ref. 68.)...

Wang, Q., Biener, J., Guo, X.C., Farfran-Arribas, E. and Madix, R.J. (2003) Reactivity of stoichiometric and defective TiO2(110) surfaces toward DCOOD decomposition. J. Phys. Chem. B, 107, 11709-11720. 

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. ... 

Stoichiometric amounts of Fe, Fe2O3, and TiO2 were milled and sintered under various conditions. 

Properties Peak-to-valley height 1.5 nm [1821], 25 nm layer, pure and stoichiometric TiO2 [1821,2673]. 

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