Nanocomposite of functionalized graphene and molybdenum disulfide as friction modifier additive for lubricant

Increasing transportation and other industrial activities since the beginning of the last century have been consuming much of our non-renewable energy resources (like petroleum) day by day, and a significant portion of the energy produced is spent overcoming friction in moving mechanical systems. More importantly, much of the fuel used to generate energy turns into CO2, which contributes to climate change and could have dire consequences. Accordingly, more effective control or reduction of friction in moving mechanical systems is very important for a sustainable future. In this contribution, a novel friction modifier has been introduced via functionalization of graphene oxide (GO) by click chemistry to increase the dispersibility of this solid additive in oil while providing advantages in properties of the oil. Furthermore, functionalized reduced graphene oxide (FrGO) has been composited with molybdenum disulfide (MoS2) and the dispersibility and also the tribological behavior of the product investigated. According to the Fourier-Transform Infrared (FTIR) and Raman spectroscopy results, GO successfully functionalized and dispersibility test confirms the highly oil dispersed nanocomposite, supported by TEM image, which shows the distribution of MoS2 nanoparticles at graphene surface. Tribology test indicates the good reduction of friction coefficient, which confirms the anti-friction behavior of the prepared nanocomposite.