Dip coating films

Abrishamchian, A., Hooshmand, T., Mohammadi, M., and Hajafi, F. (2013) Preparation and characterization of multi-walled carbon nanotube/hydroxyapatite nanocomposite film dip coated on Ti-6A1-4V by sol-gel method for biomedical applications an in vitro study. Mater Sci. Eng. C, 33 (4), 2002 -2010. 

Figure 2.19 SEM micrograph showing cleaved cross-section of BN film dip coated onto Si substrate under nitrogen.

Optical and electrical properties (film dip-coated from cyclohexane solution) ... 

FIGURE 4.12 PFOM film dip coated on glass slide from 2 wt% solution in FC72. 5-50 tm glass microspheres dusted on dried polymer film at indicated temperature. Excess particles removed with 60 psi (414 kPa) air gun. Film thickness 50 nm, image area 1x1 mm. (a) 50°C,... 

Fuertes and Menendez (2002) and Centeno and Fuertes (1999, 2001) have published a series of studies using this precursor. Centeno and Fuertes (1999) have spin coated a small amount of a novolak-type phenolic resin on the surface of carbon supports. The membranes were then carbonized in a tubular furnace from 500 to 1000°C in vacuum. The resulting membranes had O2/N2 selectivity of around 10 and CO2/CH4 selectivity of 160. This work was later extended and in that case (Centeno and Fuertes, 2001 Fuertes and Menendez, 2002) a novalak-type phenolic resin was deposited on the inner face of a ceramic tubular membrane used for ultrafiltration. The membrane was subsequently pyro-lyzed to 700°C. In some cases an oxidative pretreatment was used before pyrolysis or an oxidative posttreatment after pyrolysis. The resulting membranes had O2 permeabilities around 100 Barrers and O2/N2 selectivities around 12 at 25°C. Films dip coated with resin three times had lower permeability and only slightly higher selectivities than those dipped only once. For hydrocarbon mixtures, the separation performance was increased by several treatments air oxidation of the resin, air oxidation of the carbon, or chemical vapor deposition (CVD) posttreatment of the carbon. 

Table n. Refractive indices and vol% porosities for films dip-coated from B2 sols and AAB sols (diluted S l) as a function of aging time (or aging time normalized by the gelation time). Mass fractal dimension values are for sols aged for comparable norooaliz aging times. 

Solution Deposition of Thin Films. Chemical methods of preparation may also be used for the fabrication of ceramic thin films (qv). MetaHo-organic precursors, notably metal alkoxides (see Alkoxides, metal) and metal carboxylates, are most frequently used for film preparation by sol-gel or metallo-organic decomposition (MOD) solution deposition processes (see Sol-GEL technology). These methods involve dissolution of the precursors in a mutual solvent control of solution characteristics such as viscosity and concentration, film deposition by spin-casting or dip-coating, and heat treatment to remove volatile organic species and induce crystaHhation of the as-deposited amorphous film into the desired stmcture. 

Ti02 thin films for surface modification were prepared by sol-gel method and dip-coating... 

This is comparable to or slightly higher than the values reported for single crystal (11) and polycrystalline Ti02 (12), and much higher than those for the TiC>2 film electrode prepared by other methods such as chemical vapor deposition (13) and oxidation (14) and anodization (15) of Ti metal. The high efficiency of the dip-coated Ti(>2 film may be attributed to the porous nature of the film as described below. 

The Japanese scientists tested the fiber optic carbon dioxide sensor86, prepared by dip-coating method - the sol-gel film containing indicator dye, thymol blue, was deposited on unclad fiber. The sensitive film had both organic and inorganic parts with good permeability. The differences between attenuation in N2 gas and in CO2/N2 mixture gas increased with the CO2... 

After the precursor stock solution is prepared, various techniques can be used to coat the substrate, depending on the solution viscosity, required film thickness and coverage. The most common methods in the semiconductor industry are spin- and dip-coating. Other processes that are used for deposition include spray coating and stamping. A summary of the uses, limitations, and advantages of the various thin film deposition methods is reported in Table 2.2. 

Grosso, D. Babonneau, F. Albouy, P. A. Amenitsch, H. Balkenende, A. R. Brunet-Bruneau, A. Rivory, J. 2002. An in situ study of mesostructured CTAB-silica film formation during dip coating using time-resolved SAXS and interferometry measurements. Chem. Mater. 14 931-939. 

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