Development of an AlCl3-Urea Ionic Liquid for the Electroless Deposition of Aluminum on Carbon Nanotubes

Unlike the easy electroless deposition of other metals, the deposition of aluminum can be challenging. This is because the standard reduction potential of aluminum lies outside the electrochemical window (EW) of water. Ionic liquids such as AlCl3-1-ethyl-3-methylimidazolium chloride (EMIC) have been used because of their wide EW. Here, we introduce a novel ionic liquid for electroless deposition of aluminum by reacting AlCl3 and urea, with lithium aluminum hydride (LAH) as a reducing agent. Additionally, we report the first successful effort in coating carbon nanotubes (CNTs), as an example of nanostructures with high surface area to volume ratio, with aluminum using electroless deposition. The produced aluminum coating was found to be nanostructured, uniformly covering the CNTs and in close contact with their surfaces.