Electroplating, sonoelectrochemistry

Sonoelectrochemistry has been employed in a number of fields such as in electroplating for the achievement of deposits and films of higher density and superior quality, in the deposition of conducting polymers, in the generation of highly active metal particles and in electroanalysis. Furtlienuore, the sonolysis of water to produce hydroxyl radicals can be exploited to initiate radical reactions in aqueous solutions coupled to electrode reactions. 

Apphcations of ultrasound to electrochemistry have also seen substantial recent progress. Beneficial effects of ultrasound on electroplating and on organic synthetic apphcations of organic electrochemistry (71) have been known for quite some time. More recent studies have focused on the underlying physical theory of enhanced mass transport near electrode surfaces (72,73). Another important appHcation for sonoelectrochemistry has been developed by J. Reisse and co-workers for the electroreductive synthesis of submicrometer powders of transition metals (74). 

Lee C-W, Compton RG, Eklund JC et al (1995) Mercury-electroplated platinum electrodes and microelectrodes for sonoelectrochemistry. Ultrason Sonochem 2 S59-S62... 

Sonoelectrochemistry can be considered as the interaction of sound (hence SONO) with electrochemistry which is itself the interconversion of electrical and chemical energies. Whilst this chapter will concentrate on the application of ultrasound to important industrial processes such electrodeposition (or electroplating) and electo-or-ganic synthesis, it is important to first introduce the concept of electrochemistry, for those who are unfamiliar, so that we will have a better understanding as to what precisely happens in an electrochemical or electroplating process and how the application of ultrasound will be of benefit. 

The simultaneous application of ultrasonic irradiation to an electrochemical reaction which has been termed sonoelectrochemistry has been shown to produce a variety of benefits in almost any electrochemical process. These include enhanced chemical yield in electrosynthesis and the control of product distribution improved electrochemical efficiency in terms of power consumption, improved mixing, and diffusion in the cell minimization of electrode fouling accelerated degassing and often a reduction in the amount of process-enhancing additives required. In a major chapter devoted to this topic, Suki Phull and Dave Walton have attempted to cover the majority of applications of ultrasound in electrochemistry including electrochemical synthesis, electroanalytical chemistry, battery technology, electrocrystallization, electroinitiated polymerization, and electroplating. 

Prominent applications of sonoelectrochemistry are electroplating [296], since very smooth layers have been generated this way, furthermore production of nanomaterials, nanoparticles and very line metallic powders [297-299]. Among the latest achievements was sonoelectrochemical generation of quantum dots [300]. 

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