Plating from Nonaqueous Solutions

Electrodeposition of Pa metal has been performed from both aqueous and nonaqueous solutions. An isopropanol solution of 10-20 p,gmL Pa from 8M HCl/0.01 M HE/Pa stock was employed for quantitative electrodeposition [41]. The cell consisted of a gold-plated A1 cathode and a Pt wire anode. During deposition the current was maintained at 1 mA, which produced a potential of 400-600 V during the 90-min electrolysis. The progress of the electrolysis was externally monitored by alpha-counting of the electrolysis solution before and during the electrodeposition. Deposition studies of metal from aqueous solutions are more common. Pa was electrodeposited on platinum in 95% yield at tracer concentrations from an electrolyte of [NH4]C1/HC1 [42]. Electrochemical and chemical conditions of the plating process were described for Pu solutions, which served as a model for the other actinide elements studied. Another tracer... 

According to the definition of Brenner [43], it has become common to classify electrolytic metal deposition from nonaqueous electrolytes according to two groups, i. e., aqueous and nonaqueous . The aqueous group comprises all electrolyte systems from which metals or metallic alloys are deposited that can also be deposited from aqueous solutions. The nonaqueous group includes systems from which metals or metal alloys can be electrodeposited that cannot be plated from aqueous electrolytes. 

This chapter originates from work we have been conducting on the cathodic plating reaction of aluminum from nonaqueous solutions, a process that involves three electrons and tiiCTefore must be a multistep reaction. A particular bath for this purpose is the weU-known etheric... 

Hamadache F, Renaux C, Duvail J-L, Bertrand P (2003) Interface investigations of iron and cobalt metallized porous silicon AES and FTIR analyses. Phys Status Solidi (A) 197 168-174 Harraz FA, Tsuboi T, Sasano J, Sakka T, Ogata YH (2002) Metal deposition onto a porous silicon layer by immersion plating from aqueous and nonaqueous solutions. J Electrochem Soc 149(9) C456-C463... 

Relatively little attention has been devoted to the direct electrodeposition of transition metal-aluminum alloys in spite of the fact that isothermal electrodeposition leads to coatings with very uniform composition and structure and that the deposition current gives a direct measure of the deposition rate. Unfortunately, neither aluminum nor its alloys can be electrodeposited from aqueous solutions because hydrogen is evolved before aluminum is plated. Thus, it is necessary to employ nonaqueous solvents (both molecular and ionic) for this purpose. Among the solvents that have been used successfully to electrodeposit aluminum and its transition metal alloys are the chloroaluminate molten salts, which consist of inorganic or organic chloride salts combined with anhydrous aluminum chloride. An introduction to the chemical, electrochemical, and physical properties of the most commonly used chloroaluminate melts is given below. 

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