Graphene Oxide Coating And Apatite Formation Behavior On Titanium Surface

Metal material occupies more than 70% of the entire market of medical materials. Among all the metal materials, titanium has the most excellent performance, and has been widely used as a surgical implant material. However, the corrosion resistance and biological activity of the titanium material should be further improved. In the current study, graphene oxide(GO) was coated on the surface of titanium(Ti) by two different methods. The corrosion resistance and apatite formation behaviors of modified Ti was systematically evaluated.Firstly, the GO layer on the surface of Ti was prepared by using electrodeposition. Acid and alkali treatment was carried out before the electrodeposition to remove the oxide layer and gain an active layer on Ti surface. After that, Ti and platinum were used as the anode and the cathode, respectively, to fabricate a GO layer by electrodeposition. The composition, chemical structure and surface property were characterized by Scanning Electron Microscope(SEM), Raman and contact angle measurements, respectively. The results of EIS indicated that GO coating drastically improved the corrosion resistance. The biomineralization process was evaluated by determing the apatite formation ability of Ti in simulated body fluid(SBF). More apatite was observed on GO coated surface, which suggested that GO coating could induce the mineralization.In addition, dopamine(Dopa) was used to modify the Ti surface and enhance the adhesion between GO and Ti. Dopa and Dopa-GO layers were coated on Ti surface by immersion. The composition, chemical structure and surface property were characterized by Scanning Electron Microscope(SEM), Raman, X ray photoelectron spectroscopy(XPS), fourier transform infrared spectroscopy(FT-IR) and contact angle test, respectively. The results indicated that GO coatings could considerably improve the corrosion resistance and apatite formation ability of Ti.