Study on friction properties of polydopamine modified graphene oxide as lubricant additive

Abstract

In this study, polydopamine-modified graphene oxide (PGO) nanomaterials were prepared based on the self-polymerization of dopamine in a weakly alkaline environment. In the friction experiment, the lubricants with 0.15 wt% PGO nanomaterials have optimal friction properties. Subsequently, X-ray photoelectron spectroscopy (XPS), X-ray energy spectroscopy (EDS), and laser Raman spectroscopy were performed on the wear scar. Compared to pure oil, the friction coefficient was reduced by 31%, and the trace width was reduced by 47.69%. In addition, molecular dynamics simulations showed that PGO has the lowest diffusion coefficient among n-hexadecane and the interaction energy between PGO and n-hexadecane molecules was the largest, and oil droplets containing PGO exhibited the best adsorption performance on the surface of the Si3N4/GCr15. The results showed that compared with other additives, PGO as a lubricant additive can play a significant role in reducing friction and anti-wear.

Keywords:

• Polydopamine
• graphene oxide
• friction and wear
• molecular dynamics simulations

Disclosure statement

Authors have no conflict of interest to declare.

Additional information

Funding

This work was financially supported by National Natural Science Foundation of China (no.51805336) and Educational Department of Liaoning Province (no. LJKZ0599).