Coating electrochemical deposition

This chapter is intended to cover major aspects of the deposition of metals and metal oxides and the growth of nanosized materials from metal enolate precursors. Included are most types of materials which have been deposited by gas-phase processes, such as chemical vapor deposition (CVD) and atomic layer deposition(ALD), or liquid-phase processes, such as spin-coating, electrochemical deposition and sol-gel techniques. Mononuclear main group, transition metal and rare earth metal complexes with diverse /3-diketonate or /3-ketoiminate ligands were used mainly as metal enolate precursors. The controlled decomposition of these compounds lead to a high variety of metal and metal oxide materials such as dense or porous thin films and nanoparticles. Based on special properties (reactivity, transparency, conductivity, magnetism etc.) a large number of applications are mentioned and discussed. Where appropriate, similarities and difference in file decomposition mechanism that are common for certain precursors will be pointed out. 

There are several wet deposition procedures, including sedimentation, spin coating, electrochemical deposition, self assembly, and the Langmuir-Blodgett technique. Common for all these methods is that no ordered films of unsubstituted pure oligothiophenes can be prepared. 

Beyond PVD and CVD, there are techniques from the liquid/solution phase such as sol-gel, spray coating, spin coating, electrochemical deposition and liquid phase epitaxy. The sol-gel process is the most widely used method for the deposition of metal oxide for gas sensors. 

Several approaches have been used to create coatings made of ICPs, including casting soluble ICPs to form coatings, electrochemically depositing ICPs on the metal substrate, or blending with insulated polymers to form electrically conductive composite coatings [6, 7]. However, the application of ICPs is limited, not only for... 

Finishes for aluminum products can be both decorative and useful. Processes in use include anodic oxidation, chemical conversion coating, electrochemical graining, electroplating (qv), thin film deposition, porcelain enameling, and painting. Some alloys respond better than others to such treatments. 

Chemical Vapor Deposition Electrochemical Deposition Molecular Beam Epitaxy Atomic Layer Deposition Thermal Oxidation Spin Coating... 

Nanocarbons can also be deposited onto surfaces via electrochemistry, such as electrophoretic deposition described earlier. A method for one-step electrochemical layer-by-layer deposition of GO and PANI has been reported by Chen et al. [199]. A solution of GO and aniline was prepared and deposited onto a working electrode via cyclic voltammetry. GO was reduced on the surface when a potential of approx. -1 V (vs. SCE) was applied compared to the polymerization of aniline which occurred at approx. 0.7 V (vs. SCE). Repeated continuous scans between -1.4 to 9 V (vs. SCE) resulted in layer by layer deposition [199]. A slightly modified method has been reported by Li et al. who demonstrated a general method for electrochemical RGO hybridization by first reducing GO onto glassy carbon, copper, Ni foam, or graphene paper to form a porous RGO coating [223]. The porous RGO coated electrode could then be transferred to another electrolyte solution for electrochemical deposition, PANI hybridization was shown as an example [223]. 

Shahrokhian, S. and S. Rastgar, Electrochemical deposition of gold nanoparticles on carbon nanotube coated glassy carbon electrode for the improved sensing oftinidazole. Electrochimica Acta, 2012. 78(0) p. 422-429. 

Also, other metal oxide coatings are possible, for example, electrochemically deposited manganese dioxide. Moreover, further electrocatalytically active oxides are research objectives, for example, oxides with spinel structure such as CoMu204 [36]. 

LiMii204) electrochemical kinetics ensure that all of the surfaces of the nanotubules remain accessible to solvent and electrolyte. The polypyrrole coat was deposited by simply applying 5 al of a solution that was 1 M in HCIO4 and 0.2 M in pyrrole to the LiMn204 surface. This results in oxidative polymerization of all of the pyrrole, yielding 0.065 mg of polypyrrole per cm of Pt substrate surface [125]. 

Fuel electrode Ni-Zr02(Y2Q3) 100 pm Slurry coat-electrochemical vapour deposition... 

Spectroscopic Measurements. A Beckman Model 5230 spectrophotometer was used to record in situ UV-visible spectra of the PPy films, which were electrochemically deposited on the indium-tin oxide (ITO) coated glass (Delta Technologies). For Raman measurements a Spex Model 1403 double spectrometer, a DM IB Datamate, and a Houston Instrument DMP-40 digital plotter were employed. Details of the experimental setup for in situ Raman spectroscopy are described elsewhere (26). 

The electrochemical method is also used for the synthesis of fullerene derivatives, among them C6o fullerene salts with alkali metals crystallized at the cathode [11, 12]. No evidence on the electrochemical deposition of fullerenes on the electrodes from organic solvents is available although this method for producing fullerene coatings on metals is of indubitable practical interest. 

ZnS nanotubes have been prepared by sulfidizing ZnO templates obtained in columnar form by electrochemical deposition.77 Heating the ZnO column in H,S above 400 °C gave the ZnS coated ZnO columns. The ZnO cores were then etched out giving hollow ZnS lubes. 

All electrodes react with their environment via the surfaces in ways which will determine their electrochemical performance. Properly selected surface modification can effectively enhance the electrode heterogeneous catalysis property, especially selectivity and activity. The bulk materials can be chosen to provide mechanical, chemical, electrical, and structural integrity. In this part, several surface modification methods will be introduced in terms of metal film deposition, metal ion implantation, electrochemical activation, organic surface coating, nanoparticle deposition, glucose oxidase (GOx) enzyme-modified electrode, and DNA-modified electrode. 

HMDE (hanging mercury drop electrode) [71, 72], gold-foil [73], copper-wire [74], tungsten-wire [75, 76] and pyrolytic graphite-coated tube [78] have been used as the electrodes for electrochemical deposition, and successfully applied to the determination of Cu, Cd, Pb, Zn, Hg and so forth. In atomic absorption analysis the electrodes are usually heated directly for atomization of metals. 

A French paper described direct electrolytic deposition of molybdenum disulphide and molybdenum sesquisulphide from a mixed aqueous bath of ammonium molybdate and ammonium sulphide. G W Rowe and his co-workers produced a molybdenum disulphide coating on molybdenum wire by electrochemical deposition from a... 

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