Ormosils films

FIGURE 16.6 Scanning electron microphotos of (a) ormosil, (b) MWNTs/ormosil composite, and (c) FMC-BSA conjugate/ormosil films (adapted from [69]). 

Scanning electron microscopy (SEM) used to investigate the structure of similar organically modified silicate (ORMOSIL) films shows that certain [Ru(dpp)3]2+-doped octyl-triethylorthosilicate (triEOS)-tetra-ethylorthosilicate (TEOS) composites form uniform, crack-free xerogel films (Figure 6.6) that can be used to construct high-sensitivity oxygen... 

Metroke et al. (2002) studied the corrosion resistance properties of spray- and dip-coated 3-glycidoxypropyltrimethoxysilane (GLYMO)-tetraethoxysilane (TEOS) Ormosil films using salt spray analysis and and H- Si CP/MAS NMR (Figure 1.301). The latter indicated that organic... 

Martucci A., Innocenzi P., Pick J., Mackenzie J.D. Zirconia ormosil films doped with PbS quantum dots. J. Non-Cryst. Solids 1999 244 55-62... 

Figure 22.8 IR spectra of ormosil films doped with Er, on Si wafers, for light guiding. (After Ref. [17].)...

Tadanaga, K., Ellis, B., and Seddon, A.B. (2000) Near- and mid-infi ared spectroscopy of sol-gel derived ormosil films for photonics fi om tetramethoxysilane and trimethoxysilylpropylmethacrylate. 

The dielectric constant (k) of the resulting ORMOSIL decreases with organic content with values as low as 1.9 for films entirely made of... 

The electrochemical deposition of doped silica, ORMOSIL and related nanocomposite thin films at the surface of electrodes is opening a whole new field of applications. In the latter case, a potential is applied to an alkoxide solution which alters the pH on the electrode surface and thus enhances the rate of condensation.40 The resulting single-step... 

Figure 1.18 Electrochemical applications of ORMOSIL are due to the accessible porosity and the possibility to coat in thin films. (Reproduced from ref. 39, with permission.)...

Figure 4.5 Photodegradation of rhodamine films (A) uncoated (B) coated with an ORMOSIL coating without UV absorber (C) coated with a UV-protec-tive ORMOSIL coating.6 (Reproduced from ref. 6, with permission.)...

Thin sol gel ORMOSIL-zirconia films successfully inhibit magnesium corrosion (Figure 4.11). The film obtained by combining sol-gel monomers phenyltrimethoxysilane (PTMOS) and zirconium(iv) tetra-1-propoxide (ZrTPO) exhibits superior corrosion inhibition as compared with other films,13 while the ZrTPO-based film alone does not show significant corrosion inhibition, and the PTMOS-based film provides only moderate protection. The films are prepared by the traditional acid-or base-catalysed hydrolysis and condensation, depositing first the PTMOS film followed by the ZrTPO-based film. 

Homogeneity of dispersion and the homogeneous nature of the hybrid ORMOSIL systems result in intensely coloured films even at low thickness. Compared to organic polymers, the coloured hybrid films have enhanced mechanical properties such as greater hardness and stronger abrasion resistance. With respect to inorganic sol-gel films, hybrid films also have several advantages such as much better adhesion,... 

G. Palmisano, E. Le Bourhis, R. Ciriminna, D. Tranchida and M. Pagliaro, ORMOSIL thin films tuning the mechanical properties via a nanochemistry approach, Langmuir, 2006, 22, 11158. 

Ormosil spin-coated thin films obtained from vinyltriethoxysilane and doped with jS-di-ketonates have been recently investigated by H. Wang and collaborators. Both hydrated chelates and temaiy complexes with phen and tppo were doped at a concentration of 5 mol% (relative to Si) by a multi step sol-gel method. Out of the 12 compounds tested, [Nd(tta)3(tppo)2] yielded the best results but no quantitative luminescence data are given, preventing comparison with materials of known properties (Wang et al., 2005). 

In form of thin films Ormosils are superior to pure oxides in their lower tendency to fracture because of the presence of organic groups in their structure. The films are flexible although the Si02 content may be about 70 wt%. They have already been successfully used as matrix in solid-state dye lasers [484]. 

Marino IG, Bersani D, Lottici PP. 2000. Photo induced birefringence in drl doped sol gel silica and ormosils thin films. Opt Mater 15 175 180. 

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