Chemical silver plating

Cheng and co-workers have coated carbon fiber by chemical silver plating [49]. 

Cheng HM, Zhou BL, Zheng ZG, Wang ZM, Shi CX, Chemical silver plating on carbon-fibers. Plating and Surface Finishing, 77(5), 130-132, 1990. 

Potassium cyanide is primarily used for fine silver plating but is also used for dyes and specialty products (see Electroplating). Electrolytic refining of platinum is carried out in fused potassium cyanide baths, in which a separation from silver is effected. Potassium cyanide is also a component of the electrolyte for the analytical separation of gold, silver, and copper from platinum. It is used with sodium cyanide for nitriding steel and also in mixtures for metal coloring by chemical or electrolytic processes. 

In a related study, silver microtubules were produced by chemical deposition [38]. Similar to electrochemical deposition, the surface of the membrane must first be modified, not with a silane but with a catalyst such as Sn ions. Initially, one side of the membrane is protected by tape (Figure 1.12b) and then the surface is activated with SnCh (Figure 1.12c). The activated membrane was then placed into a solution of silver-plating solution (Figure 1.12d). This resulted in the deposition of silver over the activated surface finally the alumina membrane was dissolved away. 

The stabihty and excellent conductivity of silver helped foster the early development of silver plating in the electrochemical industry (6). Although silver is perceived to be and designated a precious metal, it is actually more abundant and less costly than most other late transition metals (5). Silver metal and silver-based compounds are utilized as catalysts, additives, oxidants, and ligand-transfer reagents in various chemical transformations (7-11). 

The same molecule has been used as probe to evaluate the SERS efficiency of substrates where ligand molecules are located in a sandwich configuration between two metal surfaces both SERS active [10]. The first one belongs to a silver plate, whose surface roughening was produced via chemical etching with ammonia and hydrogen peroxide the second is a layer of silver colloidal particles deposited after chemisorption of the ligand molecules, as shown in Fig. 20.16. 

A redox reaction involving silver is used in a chemical test to determine whether an unknown organic compound is an aldehyde. This test is called a Tollen s test. It is also sometimes called the silver mirror test because a spectacular shiny layer of elemental silver plates out on the inside of a test tube if an aldehyde is present. In this test, a silver nitrate solution is mixed with a solution of the unknown substance, and the mixture is observed to see whether the mirror forms. 

Silver is used in the mannfacture of photographic film chemicals snch as silver nitrate, as an analytic reagent in organic chemistry, as a catalyst in photo-oxidation reactions, in electrochemical reactions, in nuclear magnetic resonance and analyses, and in silver plating. 

The conventional mirror, a glass plate which is silver-plated on the rear surface by a chemical process, is a rear surface mirror. Radiation first passes through the glass substrate and is then reflected on its rear surface. 

OTHER COMMENTS silver metal and soluble silver compounds have applications in the following list of common operations used in the manufacture of silver nitrate for use in photography, mirrors, inks, dyes, and porcelain used in the manufacture of silver salts as catalysts in oxidation-reduction and polymerization reactions also utilized in chemical synthesis, in glass manufacture, in silver-plating, in photography, as laboratory reagents, and in medicine. 

FIGURE 245. From Humphry Davy, Elements of Chemical Philosophy (Philadelphia New York, 1812 first English, London, 1812) (a) Davy s voltaic pile consisting of alternating zinc and silver plates separated by moistened cloth (b) another gun-barrel experiment. In the white-hot gun barrel (free of air), potash yields metallic potassium potassium was first generated using the voltaic pile. When he discovered potassium Davy .. . actually bounded about the room in ecstatic joy. ... 

Silverlon is a knitted fabric dressing that has been silver-plated by a chemical plating technique through reduction and oxidation. This technique coats the entire surface of each individual fiber from which the dressing is made, resulting in a very large surface area for the release of ionic silver. 

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