Anatase titania, deposition

X-ray diffraction conducted on the codeposited powder revealed that the deposit obtained from a suspension of gamma alumina, which had been partially converted to the alpha phase, contained both phases of alumina. Whereas, the powder codeposited from a suspension having a 50 50 mixture of alpha to gamma alumina powder, consisted only of the alpha phase. Using a parallel plate electrode configuration, Chen et al. [31] concluded that only alpha alumina can be codeposited. Chen also observed a difference in codeposition with copper when using two different phases of the titanium oxide particle system rutile readily codeposited but anatase titania did not... 

Au/TiOz Deposition precipitation onto anatase titania 60 80 90 88... 

The deposition-precipitation method is applied to pure anatase titanias with high surface areas and silica mesostructures doped with Ti/Ti02. The effect of the type and density of surface functionalities both on the deposition of gold and on the catalytic properties of the resulting materials in the oxidation of CO in the presence of H2 are discussed. 

The decrease in activity of heterogeneous Wacker catalysts in the oxidation of 1-butene is caused by two processes. The catalyst, based on PdS04 deposited on a vanadium oxide redox layer on a high surface area support material, is reduced under reaction conditions, which leads to an initial drop in activity. When the steady-state activity is reached a further deactivation is observed which is caused by sintering of the vanadium oxide layer. This sintering is very pronounced for 7-alumina-supported catalysts. In titania (anatase)-supported catalysts deactivation is less due to the fact that the vanadium oxide layer is stabilized by the titania support. After the initial decrease, the activity remains stable for more than 700 h. 

LPD deposition of ceramic thin films is a potentially general approach to improving the abrasion resistance and thermo-oxidative stability of polymers. Dutschke et al.14,15 have deposited titania on variously treated polystyrene (PS). Continuous, adherent anatase films form on PS either after hydroxylation in... 

Though Method 2 had been reported12 to give adherent titania films only on sulfonated surfaces, we compared PMR-15 with and without CISO3H activation in a 22-h deposition. In both cases, adherent anatase films with significant (004) orientation formed, 660-690 nm on the sulfonated surface and 520-630 nm thick on the untreated substrate (Table 1). In a similar study on PS,15 films formed with or without grafted sulfonic acid groups on the surface, but were only adherent on the sulfonated surface. 

Sclafani, A. and J.M. Herrmann (1998). Influence of metallic silver and of platinum-silver bimetallic deposits on the photocatalytic activity of titania (anatase and rutile) in organic and aqueous media. Journal of Photochemistry and Photobiology A-Chemistry, 113(2), 181-188. 

Very high deposition rates of titania were observed with the mono- or dinuclear titaninm S-diketoesters Ti(mpd)(mdop)2 (28, 17-28 nmmin ) and [Ti(mpd)(mdop)(p,-OMe)]2 (9-24 nmmin ), 5 to 6 times higher than those of Ti(thd)2(OPr-/)2 (26b) °. The higher deposition rates can be explained by a weaker bonding of an ester moiety to titaninm compared to that from a ketone. The films obtained from the dimeric species were crystalline (anatase) and showed some carbon impnrity (<3%). Dimerization of complex 28 was observed when dilnting with methanol, as shown in equation 12. 

The XRD pattern of the mix-TiSi sample showed distinct titania anatase peaks due to the Ti02 component, but no XRD detectable peaks of TiOz crystallites (d > 5 nm) were observed for the ALD samples, even above the theoretical monolayer coverage of 5.5 Ti atoms/nm upport [4,10]. The deposition of highly dispersed titania only caused intensity masking of the broad amorphous line of silica centered at 29 = 23° [10], Nevertheless,... 

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