Oxides TiO2 structure

For rutile, as a more complex oxide crystal structure, STM of TiO2(110) (Figure 15.23b) reveals also the occurrence of monoatomic steps only however, in this case, several different step directions and step terminations are possible [104]. 

Onishi, H., Fukui, K. and Iwasawa, Y. (1995) Atomic-scale surface structures of TiO2(110) determined by scanning tunneling microscopy A new surface-limited phase of titanium oxide. Bull. Chem. Soc. Jpn., 68, 2447—2458. 

Figure 3.11 shows the rates of CO oxidation over model catalytic systems, Au/TiO2(110) and well-ordered Au mono- and bilayer structures. The maximum... 

Materials. The titanium dioxide powders were rutile in structure (obtained from the Titanium Division, National Lead Co., Amboy, N. J.), with nominal specific surface areas of 10 and of 100 sq. meters per gram. Chemical analysis by the supplier showed negligible impurities except for 0.8% sodium oxide in the Ti02-100 and traces of iron in both the TiO2-10 and the TiO2-100. The presence of iron was confirmed by the nature of the decay of the neutron irradiation—induced radioactivities. 

Although the Ti02(l 10)1x1 surface is considered the best-characterized, prototypical metal oxide surface, the above summary clearly shows that its atomic-level structure is significantly more complex than originally assumed. The recent STM results clearly indicate that both the oxidation conditions and the history of the TiO2(110) sample have significant influence on the morphology of the surface, the presence of strands, rosettes. 

Thallium(I) oxide, H2O, is a well-characterized compound and a useful source of Tl salts. Matrix isolation studies of the solid gave structural data in agreement with spectroscopic results. The so-called peroxide TIO2 is obtained electrochemically from aqueous TI2SO4, but the properties include insolubility in water, alkali and some dilute acids, and treatment with dilute HCl yields oxygen. The stoichiometry suggests that the compound is in fact a superoxide, and this has been confirmed by spectroscopic studies on frozen matrices. 

The addition of a second oxide to the titania surface produces new nucleation sites for Au and improves the dispersion of the admetal. " In the CeO /TiOgCllO) systems, the Ce cations adopt a structural geometry (Fig. 6.2A) and an oxidation state (-1-3) which are quite different from those seen in bulk ceria or for ceria nanoparticles deposited on metal substrates. On TiO2(110), one has CegOg dimers that join forming wire-like structures on the terraces of the titania substrate. ... 

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