Electrochemical characterisation of oxide films formed on Ti-6Al-4V alloy implanted with Ir for bioengineering applications

Iridium oxide anodically grown on pure iridium is known to have excellent properties for use as neural stimulating electrodes. Its mechanical properties, however, make pure iridium difficult to fabricate into small electrodes. In this work, the commercial Ti-Al-4V alloy surface modified by ion implantation with iridium is tested for its electrochemical properties, aiming at its use as a stimulating electrode. The results show that an oxide film with good charge storage capacity is formed on the surface of the material. The properties of the electrode are compared with those of pure iridium. Characterisation was made by cyclic voltammetry, electrochemical impedance spectroscopy and XPS.