Preparation and Tribological Properties of a Multilayer Graphene-Reinforced TiO₂ Composite Nanolubricant Additive

Abstract

The unique structure and physical properties of graphene and anatase TiO2 make them suitable for use as additives for engine lubricants. This study describes the use of dielectric barrier discharge plasma-assisted ball milling to synthesize a multilayer graphene-reinforced TiO2 composite nanolubricant additive (MGTC). A variety of physical and chemical tests were performed to characterize the resulting experimental materials, including X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Raman, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Four-ball friction and wear testing machines were used to study the tribological properties and extreme pressure anti-wear properties of a base oil containing 0.1, 0.5, 1.0, and 1.5 wt % of the modified TiO2. Raman spectroscopy, XPS, SEM, and energy-dispersive spectrometry (EDS) analyses were used to examine and analyze the microstructure of the friction pairs. As a result of the plasma-assisted ball milling process, expanded graphite was successfully separated into multilayer graphene nanosheets, and spherical TiO2 was successfully bonded to the nanosheets of the multilayer graphene. The 1.0 wt % composite oil was found to provide good friction reduction and wear resistance. It had a film thickness of 27.5 nm, which was 167% thicker than base oil. Due to its excellent dispersion stability, the MGTC nanocomposite exhibited excellent lubrication performance, which was attributed to the formation of carbon protective films, titanium dioxide deposition films, transfer films, and the occurrence of nano ball effects on the surface of friction pairs.

Tribochemistry of mercaptoimidazoline as an additive in emulsion between self-mated GCr15 ball interfaces and its friction-reduction mechanism

“…Figure 11 shows the XPS analysis of 2-MBTA. The peaks of C 1s at 284.8 eV, 286.44 eV, and 288.17 eV correspond to the C-C, C-O, and C=O bond [31], respectively. This indicated the 2-MBTA adsorption onto the metal surface and subsequent oxidation.…”

Brown TiO2-Based Fe–Ni Thiospinel Binary Nanocomposite as a Sustainable Catalyst with Synergistic Improvement Assisted by H2O2 and Ascorbic Acid for Round-the-Clock Removal of Rhodamine B

“…Four characteristic peaks at 131, 371, 484, and 605 cm −1 were detected in the SDFNSBT materials, well assigned to the anatase-phase Raman vibration mode of E g , B 1g , A 1g , and E g , respectively. 52 Therefore, the blue shift in Raman bands caused by the breaking of the original symmetry of the TiO 2 lattice confirmed the presence of defective TiO 2−x NCs in the SDFNSBT NCP. 42 3.2.…”