Characterization of chemically treated titanium using soft X-ray fluorescence

High energy resolution soft X-ray fluorescence measurements of commercially pure (cp-Ti) and chemically treated Ti (Ti + HCl and Ti + HCl + NaOH) are presented. They show the formation of thick hydrogen-(TiH2) and oxygen-passivated (TiO2) layers on Ti + HCl and Ti + HCl + NaOH, respectively; it is shown that the oxygen-passivated layer has primarily anatase structure. A bone-like carbonated apatite layer is found to be formed on the surface of chemically treated Ti after exposure to simulated body fluid (SBF). The spectroscopic results indicate that (CO3)2− substitutes both OH− (type A substitution) and (PO4)3− (type B substitution) sites in the apatite structure.