Optimization of Cu and Zn co-doped PEO titania coatings produced in a novel borate-based electrolyte for biomedical applications

Plasma Electrolytic Oxidation is gaining an increasing interest as surface modification technique for the fine tuning of both the chemical composition and the morphology of the surface of medical devices. Here, we propose a novel alkaline electrolyte, mainly composed of sodium tetraborate, to produce compact coatings with a high surface porosity and a Cu- and Zn-doped titania microstructure. A systematic exploration of the process parameters led to the identification of the optimal conditions to produce highly homogeneous coatings with micrometric pores and the doping of the outermost oxide layers. The obtained coatings show optimal chemical and topographical features for potential use for bone-contact applications.