Induced codeposition

Induced Codeposition of Alloys of Tungsten, Molybdenum and Rhenium with Transition Metals... 

In this section, the process of electrodeposition is reviewed briefly, and its place in the general context of electrode reactions and charge transfer across the metal/solution interface is set (Section 1.1). In Section 1.2, special emphasis is given to deposition of alloys, and particularly to anomalous deposition of alloys (Sections 1.2.3 and 1.2.4). Next, the phenomenon of induced codeposition is defined, and possible mechanisms are discussed briefly (Section 1.2.5). Several electroless (Section 1.2.6) and electrodeposition processes, in which induced codeposition plays a role, are mentioned. A more extensive discussion of electrodeposition of W-, Mo- and Re-based alloys is included in Section 2. Typical... 

Although this chapter is about induced codeposition, and is not meant to deal specifically with anomalous alloy deposition, a few general comments would seem to be appropriate. 

Certain elements, such as W, Mo, Ge and P cannot be deposited alone from their aqueous solutions. Nevertheless, they may readily be codeposited with iron-group elements. The term induced codeposition was coined by Brenner in 1963 to describe a situation where... 

Electroless deposition, or autocatalytic plating, may be defined as deposition of a metal coating by a controlled chemical reduction, catalyzed by the metal or alloy being deposited. Electroless deposition has been known for a long time. One of its early uses was the deposition of a mirror-like layer of silver on the internal surfaces of Dewar flasks for improved thermal isolation, and as the back coating of mirrors. Later, it was used for deposition of different metals and alloys, and even for induced codeposition of alloys. 

With respect to the last type of mechanism, Gileadi and coworkers recently studied the induced codeposition of W-Ni from moderately alkaline baths containing citrate as a complexing agent, with or without ammonia. The range of bath compositions and operating conditions is shown in Appendix A. The working hypotheses in these studies were that ... 

Further support for the role of the mixed-metal complex in induced codeposition of W is the measured effect of mass transport. Gileadi et al. used rotating cylinder electrode (RCE) experiments to study this effect in two ways - by varying the rotation rate at a... 

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