Double layer graphene oxide-PVP coatings on the textured Ti6Al4V for improvement of frictional and biological behavior

Mahbobeh Sadeghi, Mahshid Kharaziha, Hamidreza Salimijazi

In this study, double-layer coatings of graphene oxide (GO)-poly(vinyl pyrrolidone) (PVP) (PGO) were deposited on the micro-textured Ti6Al4V substrates by electrophoretic deposition. Results revealed that the combination of micro-dimples and bi-layer PGO coatings significantly reduced the friction coefficient of textured Ti6Al4V from 0.5 to <0.03. PGO layer provided both relatively smooth surface of PVP for suitable adhesion and a rigid layer of GO for load bearing. Moreover, the textured micro-dimples acted as sinks to preserve the PVP and GO fragments and wear debris leading to sustain low friction coefficient for a long period of operation. In addition, our results demonstrated that the bi-layer PGO coating on the micro-textured Ti6Al4V substrate resulted in significant improvement of MG63 cell attachment and proliferation. In summary, PGO coated textured Ti6Al4V with simultaneously improved wear resistance and biological function have the potential for orthopedic implants.