Synthesis of Core-Shell Al/tiO2 Nanotube Composites by Electrochemical Methods

Abstract

In many material applications such as energy storage, photovoltaic, optoelectronic devices, etc., there is a need for complex structures prepared with low cost and simple techniques such as electrochemical methods. In this paper, the electrochemical growth process of aluminium nanostructure on TiO2 nanotubes from room temperature ionic liquid containing AlCl3 electrolyte has been investigated. Firstly, the TiO2 nanotubes were formed by electrochemical anodization of Ti foil, and then the nanotubes coated with Al by electrodeposition, for the formation of Al/TiO2 nanotube nanocomposites. The effect of the AlCl3 concentration in electrolyte on the nucleation and growth process of Al has been studied. The loading of the deposit has been well controlled by the electrochemical charge measured during deposition process. The morphology, structure and compositions of the composites have been characterized by X-ray diffraction, Scanning Electronic Microscopy coupled with Energy Dispersive X-ray Spectroscopy, and Transmission Electronic Microscopy. It is shown that polycrystalline aluminium grains are successfully deposited on the surface of the nanotubes filling the spacing in-between nanotube walls. Since both Al and TiO2 nanotubes have several interesting properties, the synthesis of their nanocomposites expects to gain great interest of various technological applications.