▎ 摘　　要

Graphene oxide (GO) nanosheets were decorated with copper borate (CuB) nanoparticles via a liquid phase-based ultrasonic-assisted stripping method to afford CuB/GO nanocomposites. The as-prepared nanocomposites were characterized using FT-IR, XRD, Raman, UV-vis, TEM and AFM techniques, revealing CuB nanoparticles anchored on the surface of GO nanosheets. To inhibit the agglomeration and improve the dispersion stability of the nanocomposites in the base oil, the CuB/GO nanocomposites were modified with oleic diethanolamide (OD), to obtain oleic diethanolamidecapped copper borate/graphene oxide nanocomposites (OD-CuB/GO). The tribological properties of these nanocomposites, when used as an additive in base oils with different viscosities, were evaluated with a four-ball friction and wear tester. The results showed that when the OD-CuB/GO nanocomposites were added into the base oil at a mass fraction of up to 4.0%, the friction coefficient and wear scar diameter of the OD-CuB/GO-based oil were respectively about 43.6% and 49.3% lower than those of the base oil. This indicates that the OD-CuB/GO nanocomposites can significantly improve the tribological properties of the base oil and possess a good anti-wear ability and loadcarrying capacity.