Nano/micro tribological behaviors of a self-assembled graphene oxide nanolayer on Ti/titanium alloy substrates

In this study, reduced graphene oxide (RGO) layer is prepared on a self-assembled monolayer (SAM) of 3-aminopropyltriethoxysilane (APTES) modified surface of deposited Ti substrates or Ti–29Nb–13Ta–4.6Zr (TNTZ) alloy substrate. The surface morphology was measured by SEM and AFM. Tribological behaviors in nano scale by AFM and in micro scale by UMT-2 were investigated and compared with titanium substrate, APTES SAM and GO-APTES nanolayer. XPS, water contact angle (WCA) and ellipsometry tests were carried out as assistant methods to discuss the tribological mechanisms. In both nano and micro scale tribological tests, the prepared film holds remarkable tribological properties. It also shows good anti-wear performance in our designed bio-tribological test. Nano and micro tribological mechanisms of the film are discussed.