Electroless Deposition of Aluminum from AlCl₃/LiAlH₄/Ether Solvents (1)~ Optimization of deposition conditions ~

In this study, electroless deposition of aluminum (Al) was examined with baths of AlCl₃/LiAlH₄/ether solvents and catalysts formed on substrate surfaces. To deposit an electroless thick Al layer, a Cu substrate, a Ti compound catalyst and diethyl ether or dibutyl ether solvents should be used for the deposition process. Al deposits with a thickness of 15 µm for a deposition time of 2 h were obtained. The rate of Al deposition was 15±2 µm h^-1. The addition of dicarboxylic acids to the bath, such as glutaric acid and thiomalic acid, could improve the brightness of the deposited Al surface. As an example of an application for electroless Al, the deposition of Al on the surface of cup-stacked carbon nanotubes with diameters from 30-50 nm was successfully conducted with a bath comprising AlCl₃/LiAlH₄/diethyl ether and a Ti catalyst.