Nickel electrodeposited

A. W. HothersaH, "The Adhesion of Electrodeposited Nickel to Brass," paper presented to Electroplaters and Depositors Technical Society, Northampton Polytechnic Institute, London, UK, May 18, 1932. 

Despite the large differences in respect of other mechanical properties, it has been established that the wear resistance of copper deposits, which is markedly inferior to, for example, that of electrodeposited nickel, is not significantly affected by either type of bath or addition agents. 

A major advantage of the electroless nickel process is that deposition takes place at an almost uniform rate over surfaces of complex shape. Thus, electroless nickel can readily be applied to internal plating of tubes, valves, containers and other parts having deeply undercut surfaces where nickel coating by electrodeposition would be very difficult and costly. The resistance to corrosion of the coatings and their special mechanical properties also offer advantages in many instances where electrodeposited nickel could be applied without difficulty. 

Preparation of basis metals for plating Preliminary cleaning of various basis metals follows the broad principles used for electrodeposited nickel. 

Apply an external current briefly so as to electrodeposit nickel. 

Resistance to corrosion Most authors who compare resistance to corrosion of electroless nickel with that of electrodeposited nickel conclude that the electroless deposit is the superior material when assessed by salt spray testing, seaside exposure or subjection to nitric acid. Also, resistance to corrosion of electroless nickel is said to increase with increasing phosphorus level. However, unpublished results from International Nickel s Birmingham research laboratory showed that electroless nickel-phosphorus and electrolytic nickel deposits were not significantly different on roof exposure or when compared by polarisation data. 

Electroless nickel-phosphorus should not be used with either fused or hot, strong, aqueous caustic solutions because the coating offers lower resistance to attack than does electrodeposited nickel. As-deposited electroless nickel-boron, however, offers good resistance to hot aqueous caustic solutions It is also resistant to solutions of oxidising salts such as potassium dichromate, permanganate, chlorate and nitrate. 

A wide range of applications for hard, wear-resistant coatings of electroless nickel containing silicon carbide particles have been discussed by Weissenberger . The solution is basically for nickel-phosphorus coatings, but contains an addition of 5-15 g/1 silicon carbide. Hiibner and Ostermann have published a comparison between electroless nickel-silicon carbide, electrodeposited nickel-silicon carbide, and hard chromium engineering coatings. 

Electroless nickel coatings containing PTFE particles have been discussed by Tulsi, and non-stick coatings of electrodeposited nickel containing 30% by volume PTFE particles are described by Naito and Otaka . They found that the addition of organic additives to increase the hardness of the nickel matrix to 500-600 Hy reduced the incorporation of the PTFE to 10-15% by volume. 

Tubes and Perforated Tubes Electrodepositing nickel non-adherently all over the curved surface of a cylinder, and then sliding off the coating, produces a tubular nickel product. Some tubes manufactured in this way are plain, but most are perforated. They are used industrially for screen printing textiles, carpets and wall paper . 

Chonglun F., Piron D.L., Paradis R, Hydrogen evolution on electrodeposited nickel-cobalt-molybdenum in alkaline water electrolysis, Electrochim. Acta, 39(18), 2715-2722,1994. 

Figure 12.6. Resistance-temperature curves for electrodeposited nickel films about 20 [xm thick.

Sulfur impurities can be detrimental to nickel deposits. Specifically, an increase in sulfur couteut is known to reduce the fracture resistance of electroformed nickel. Since sulfur has a direct influence on the properties of electrodeposited nickel, if no other impurities are present in the deposit, hardness by itself can be used as an indicator of sulfur impurity content. 

In general, one can expect systems like these to have properties different from those in bulk materials, where most ions are in a crystalline enviromnent that is, they do not see the surface. Here, most atoms know they are near an interface specifically, in a noncrystaUine, nonperiodic enviromnent. As shown in Table 17.1 and Figure 17.4, the Knoop hardness of these films is increased from 2.9 to 5.6 times the value for the harder of the two comp)onents, the electrodeposited nickel. 

Kirkendall void formation can, however, be prevented from occurring by choosing the right metal species. For example, whereas platinum coating on copper is subject to the Kirkendall void creation process, the same coating on electrodeposited nickel is free of it even if heated to as high as 600°C for many hours (more than 10 hours ). 

Enones are selectively hydrogenated electrochemically at the conjugated alkene bond. A high degree of selectivity is achieved at an electrodeposited nickel surface... 

A Raney nickel surface is also suitable for electrocatalytic hydrogenation [205]. This surface is prepared by electrodepositing nickel from a solution containing suspended Raney nickel alloy (Ni 50% A1 50%). Some alloy particles stick to the surface, which is then activated by leaching the aluminium using hot aqueous sodium hydroxide. Cyclohexanone, acetophenone and benzil have been converted to the corresponding alcohol and there is no stereoselectivity for the formation of hydrobenzoin from benzil. 

THE PROBLEM OF HYDROGEN PERMEATION INTO THE BORON DOPED ELECTRODEPOSITED NICKEL FILMS... 

Figure 28. CVs of GOx /NiOx modified GC electrode at various scan rate in pH 7 PBS, from inner to outer, 10, 20, 30, 40, 50, 60, 70, 80, 90 and lOOmVs 1. Reprinted from Biosensors and Bioelectronics, 22, ASalimi, E. Sharifi, A. NoorBakhash, S. Soltanian, Immobilization of glucose oxidase on electrodeposited nickel oxide nanoparticles Direct electron transfer and electrocatalytic activity,3148,Copy eight (2007), with permission from Elsevier.

S. Soltanian, Immobilization of glucose oxidase on electrodeposited nickel oxide nanoparticles Direct electron transfer and electrocatalytic activity,3151, Copyeight (2007), with permission from Elsevier. 

Xia YQ, Sasaki S, Murakami T et al (2007) Ionic liquid lubrication of electrodeposited nickel-SijN composite coatings. Wear 262 765-771... 

Goods SH, Kelly JJ, Yang NYC (2004) Electrodeposited nickel-manganese an alloy for microsystem applications. Microsyst Technol Micro Nanosyst Inf Storage Process Syst 10 498-505... 

A literally nanoarchitectured electrode was reported by Owen et al. [64,65], who electrodeposited nickel/nickel oxide, which is regarded an electrochemi-cally extremely important material whenever applications like fuel cells, the electrolysis of water, batteries or catalysts for the electrochemical hydrogenation of organic species are concerned. Mesoporous nickel electrodes have been electrodeposited by reduction of a nickel(II) solution dissolved within the aqueous... 

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