SEM and EDS Analysis of Surface Layer Formed on Titanium After Plasma Electrolytic Oxidation in H3PO4 with the Addition of Cu(NO3)2

Abstract
Plasma Electrolytic Oxidation—PEO (Micro Arc Oxidation—MAO) as a surface layer modification method is increasingly being used for biomaterials. The surface after that oxidation is more biocompatible than that after other electrochemical treatments. The analyses of the titanium surface after PEO treatment show that the thickness of the surface layer is about 10 μm, and it contains oxygen (43.8 wt%), titanium (26.26 at%) and phosphorus (25.08 wt%) with some amount of copper (4.85 wt%). The depth analysis by a cross section shows there are three phases: the first one is the matrix as a pure titanium, the second one is an amorphous phase consisting of titanium (34.64 wt%), oxygen (42.13 wt%) and phosphorous (23.23 wt%), and the third outer layer composed of titanium (40.98 wt%), oxygen (40.59 wt%), phosphorus (16 wt%) and copper (2.43 wt%).