Electroless Deposition of TiO2 ∕ Ti onto Aluminum Substrates

Abstract

The stability of titanium-based biomaterials has been linked to film covering the Ti metal. However, the conventional techniques for depositing render its surface modification very difficult. A unique alternative approach appears to be the use of electroless plating. This work discusses an approach for designing membrane using electroless deposition. Deposition was achieved via the chemical reduction of titanium(IV) isopropoxide on aluminum substrates in aqueous-alcoholic media (80% propanol:20% water) using anthracene as reducing agent. The aluminum substrates were initially sensitized and activated with and in that order, to induce the selective reduction of titanium metal ions. Ethylenediaminetetraacetic acid was used as complexing agent while 2-mercaptobenzothiazole served as stabilizer. Subsequent characterization using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy, and energy dispersive spectroscopy and electrochemical techniques confirmed that titanium oxides/titanium metals have been electrolessly deposited. Note that aluminum substrates that were not sensitized did not show any evidence of the presence of titanium, indicating that the sensitization and activation steps were necessary to initiate the electroless deposition of titanium. XPS confirmed that the electrolessly deposited surfaces contained Ti atoms in two different chemical environments, specifically atoms.