Electrode spin coating

Tetrathiafulvalene (TTE) has also been used in electrochromic devices. TTE-based polymers spin-coated onto transparent electrode surfaces form stable thin films with reproducible electrochromic properties (100). The slow response of these devices has been attributed to the rate of ion movement through the polymer matrix. 

The rqjroducibility of polymer film formation is greatly improved by the spin coating technique where the polymer solution is applied by a microsyringe onto the center of a rapidly rotated disk electrode Rather thick films can be produced by repeated application of small volumes of stock solution. A thorough discussion and detailed experimental description of a reliable spin coating procedure was given recently... 

The clay mineral bentonite (sodium montmorillonite) has an excellent ion exchange and adsorption capacity. Films can be applied to electrode surfaces from colloidal clay solutions by simple dip or spin coating that become electroactive after incorporation of electroactive cations or metal particles 136-143)... 

The synthesis and electrochemical properties of carbon films prepared from positive photoresist have been reported.The initial direction for this work was the fabrication of carbon interdigitated electrodes. In this work, positive photoresist was spin coated on a silicon substrate, patterned by photolithography, and pyrolyzed to form the carbon electrode. In more recent work, laser excitation has been used to both pyrolyze the film and to write the electrode pattern. ... 

In an attempt to combine band-Uke charge carrier motion realized in an -inevitably fragile - crystalline FET structure with structural robustness and flexibility, Sakanoue and Sirringhaus [167] prepared FETs using spin coated films of 6,13-bis(triisopropylsilylethynyl)(TIPS)-pentacene films in contact with a perfluorinated, low dielectric-constant polymer gate electrode. The (linear) hole mobility at room temperature is 0.8 cm /V s with tendency of an apparent band-like negative temperature coefficient of the mobility (d/i/dT < 0). 

Schafer and coworkers [23] developed a QCM-IL sensor for use as an artificial nose using the ubiquitous [C4Cilm][PFg]. The IL was spin coated onto the surface of a 10 MHz AT-cut quartz crystal with gold electrodes. The work specifically studied the response of the sensor to ethyl acetate. The deposition of the IL on the surface of the electrode decreased the resonance frequency of the QCM by 2017 Hz. Exposure to increasing amounts of ethyl acetate vapor produced a linear increase in frequency, which was attributed to a progressive decrease in viscosity of the IL upon adsorption of the analyte. The response time, given as the time to full saturation of the... 

A polymer thin film having a thickness of 50 nm containing the step 5 product was formed by a spin coating method. The polymer thin film contained an Au electrode that had been vapor deposited and where the source electrode and drain electrode had a channel width of 2 mm and a channel length of 20 pm. 

Gratzel and co-workers reported an N3-dye-sensitized nanocrystalline Ti02 solar cell using a hole-transport material such as 2,2, 7,7 -tetrakis (N, N-di-p-methoxyphenyl-amine) 9,9 -spirobifluorene (OMeTAD) as shown in Fig. 17, as a solid electrolyte [143]. OMeTAD was spin-coated on the surface of the N3 dye/Ti02 electrode and then Au was deposited by vacuum evaporation as the counterelectrode. The cell efficiency was 0.7% under 9.4 mW/cm2 irradiation, and 3.18 mA/cm2 of Jsc was obtained under AM 1.5 (100 mW/cm2) [143]. The maximum IPCE was 33% at 520 nm. The rate for electron injection from OMeTAD into cations of N3 dyes has been estimated as 3 psec, which is faster than that of the I ion case [144]. 

A number of different methods can be used to prepare polymer film-coated electrodes. The simplest is to dip the surface to be coated into a solution of the polymer, remove the electrode from the solution, and allow the solvent to evaporate. While this method is simple, it is difficult to control the amount of material that ends up on the electrode surface. Alternatively, a measured volume of solution can be applied to the surface to be coated. This allows for accurate control of the amount of polymer applied. The polymer film may also be spin-coated onto the electrode surface. Spin-coating is used extensively in the semiconductor industry and yields very uniform film thicknesses. 

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