Formation of titania/hydroxyapatite composite films by pulse electrolysis

Abstract

The aim of this study was to examine the formation of titania (TiO 2)hydroxyapatite (HAp) composite films on a titanium substrate using anodic-cathodic pulse electrolysis. The TiO2/HAp composites were coated on commercially pure titanium plates (surface area: 1.0cm2) using pulse electrolysis in an autoclave in an aqueous solution that consisted of 0.3 mM Ca(H2PO4)2 and 0.7 mM CaCl 2 and pH = 5.5 at 120°C. The pulse potentials were applied at +8.7 V vs. Ag/AgCl sat. KCl as anodic potential and -9.3 V as cathodic. The total electrolysis time was 1800 s. We examined the effects of the electrolysis cycle (60-600 s) and duty ratio on such properties of the coatings as the surface morphology, the amount of precipitated HAp, and the size of the HAp crystals. Prior to the pulse electrolysis, cathodic and anodic electrolysis experiments were also conducted. With pulse electrolysis, we could obtain TiO2/HAp composite films with fine HAp particles dispersed uniformly on a thin TiO2 coating. © 2007 The Japan Institute of Metals.