Reducing emissions of exhaust particles using the synergy of molybdenum disulfide and carbon nanotubes in engine oil additives

Abstract

Abstract To reduce emissions of exhaust particles, using oils with improved properties has been proposed. Nanoadditives can be used to enhance lubricating properties of engine oils. Although many additives have been developed, molybdenum disulfide and carbon nanotubes have attracted significant attention. In this study, we demonstrate that hybrid nanostructures based on these unique materials (MoS2/CNTs) positively affect lubricating properties of the engine oil. Hybrid nanostructures were produced via wet chemical synthesis in impinging jet reactor. This method is characterized by easy scalability and possible continuous operation, which are crucial in material commercialization. Various concentrations of the oil nanoadditives were tested. The application of 0.5 wt% suspension produced the best results, reducing the friction factor at the engine operating temperature by up to 26%. Nanoadditives protected the lubricated parts, causing their wear to be considerably lower than the base oil. The effect of nanoadditives on the quality of exhaust gases was also investigated. The application of the oil with MoS2/CNT reduced the emissions of solid particles in the exhaust gas of a gasoline engine. This research showed that MoS2/CNTs can be successfully used as nanoadditives in engine oils for improving tribological properties, enhancing anti-wear performance, and reducing particle emissions in exhaust gas.