Lewis acids chloroaluminate electrodeposition

The Lewis acidic chloroaluminate ILs are suitable for the electrodeposition of aluminum-containing alloys. Many examples have been published but those that have been reviewed in detail by Stafford and Hussey [1] will not be included in this section. 

Chloroaluminate(III) ionic liquid systems are perhaps the best established and have been most extensively studied in the development of low-melting organic ionic liquids with particular emphasis on electrochemical and electrodeposition applications, transition metal coordination chemistry, and in applications as liquid Lewis acid catalysts in organic synthesis. Variable and tunable acidity, from basic through neutral to acidic, allows for some very subtle changes in transition metal coordination chemistry. The melting points of [EMIM]C1/A1C13 mixtures can be as low as -90 °C, and the upper liquid limit almost 300 °C [4, 6]. 

The electrodeposition of metals and alloys has been investigated extensively in the chloroaluminate ionic liquids. Many kinds of metal salts, mostly chlorides, can be dissolved in ionic liquids with their Lewis acidity or basicity controlled by changing the composition of AICI3. In the case of acidic ionic liquids that contain AICI3 at more than 50 mol%, a dimeric chloroaluminate anion, AI2CI7, acts as a Lewis... 

Callium Elemental gallium can be electrodeposited from both chloroaluminate [17] and chlorogallate [18] ionic liquids. In the latter case l-ethyl-3-methylimidazohum chloride was mixed with GaQs, thus giving a highly corrosive ionic liquid that was studied for GaAs thin film electrodeposition. In the chloroaluminates Ga can be deposited from Lewis acidic systems. It was found that the electroreduction from... 

Zheng Y, Zhang S, Lii X, Wang Q, Zuo Y, Liu L (2012) Low-temperature electrodeposition of aluminium from lewis acidic l-allyl-3-methylimidazolium chloroaluminate ionic liquids. Chin J Chem Eng 20(1) 130-139. doi 10.1016/S1004-9541(12)60372-3... 

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