Tribological behaviors of OA-ZIF-8/GO as additives of the lubricating oil

Abstract

In this paper, oleic acid surface-modified zeolitic imidazolate framework-8/graphene oxide (OA-ZIF-8/GO) nanocomposites were prepared by a facile in-situ synthetic method. The as-prepared composite samples were analyzed and characterized by means of transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermal gravimetric analysis (TG). The tribological behaviors of the OA-ZIF-8/GO with different GO contents as the lubricanting oil additives were investigated comparatively by a four-ball tribological machine. The results showed that compared with the base oil, the addition of the OA-ZIF-8/GO with different GO contents all can reduce friction and wear. The oil sample with 1.0 wt% of OA-ZIF-8/GO (53%) nanocomposite had the lowest friction coefficient and wear scar diameter. The reduction of friction coefficient and wear scar diameter is attributed to a stable protective film formed on the worn surface via physical deposition and a complicated tribochemical reaction. The study provides a strategy for fabricating graphene-based nanocomposites that were used for lubricating oil additives.