Processing and Characterization of Biocompatible Titania Coatings by Electrophoretic Deposition

Abstract

The electrophoretic deposition (EPD) technique was developed for depositing TiO2 films on stainless steel (SS) and titanium substrates. Titania coatings were obtained in conditions of optimal solution stability using acetylacetone suspensions of TiO2 nanoparticles and I2 at pH≈ 5. Deposition tests were carried out at 10V for varying times. The deposit thickness was seen to increase with EPD time, revealing that the deposits grew quickly for times <120 s, reaching a saturation value at longer times. The substrates were treated by physical and chemical methods before EPD in order to improve the adhesion of the films. The EPD coatings were sintered at 700, 800 and 900 °C under controlled argon atmosphere or in vacuum to study the influence of sintering atmosphere on crystalline phase transformation. The TiO2 coatings were characterized by XRD using Rietveld analysis. The results showed that TiO2 films on Ti substrates (chemically leached before deposition) had better adherence, homogeneity and density than those on SS. The coatings sintered al 700°C in vacuum resulted in a major proportion of anatasa phase. The porosity of the titania coatings sintered at 700°C (2 hr) in vacuum was calculated to be 19% .

Application of the Multi-Step EPD Technique to Fabricate Thick TiO2 Layers: Effect of Organic Medium Viscosity on the Layer Microstructure

“…8 The TiO 2 based layers have also been employed in biomaterials-related applications such as implants. 9 In most industrial applications of TiO 2 , crack-free thick or thin films with a uniform microstructure are required. In order to obtain such high quality levels, numerous methods such as sputtering, 10 sol gel, 11 doctor blade, 12 screen printing, 13 plasma spray, 14 atomic layer deposition, 15 and chemical vapor deposition 16 have been employed.…”

“…TiO 2 has been widely used as a photocatalyst, dye sensitized solar cell (DSSC) film, gas sensor, and protective coating . The TiO 2 based layers have also been employed in biomaterials-related applications such as implants . In most industrial applications of TiO 2 , crack-free thick or thin films with a uniform microstructure are required.…”

Titanium Oxide (TiO2) Coatings on NiTi Shape Memory Substrate Using Electrophoretic Deposition Process

“…In order to reduce releasing of Ni 3+ ions, to increase bone adhesion to the metal implant surface, and minimize their direct contact with body fluids, TiO 2 coatings have been used on metallic implants. TiO 2 coating has proper anti-bacterial and biocompatibility properties [4].…”

“…Rutile is desirable phase in clinical applications due to the high corrosion protection of metallic implants and high biocompatibility. Also anatase phase has bioactivity properties [4].…”