Lubrication performance of MXene/Brij30/H2O composite lamellar liquid crystal system

The lamellar liquid crystal (LLCS) system constructed by surfactant aggregation was demonstrated to exhibit superior tribological properties due to its unique lamellar structure and creep recovery properties. However, the lubrication performance of this kind of liquid crystal system was greatly hindered by its soft nature. Emerging as two-dimensional material, MXene has been promising candidate in tribology on account of its unique layer structure and versatile composition . Taking account of the above fact, herein, nonionic surfactant polyoxyethylene lauryl ether (Brij30), MXene (Ti 3 C 2 T x ), and H 2 O were employed to construct a triple-component composite LLCS system and the related tribological properties were systematically investigated. The results demonstrated that the lubrication performance of the liquid crystal system formed in the presence of Ti 3 C 2 T x was significantly improved compared with that of Brij30/H 2 O LLCS. The average friction coefficient of the composite LLCS system was in the range of 0.1155–0.1266, and the best lubrication performance was achieved when the Ti 3 C 2 T x content was kept as 6 mg/mL. MXene is also able to achieve good dispersion in liquid crystal systems. The enhanced lubrication performance of the composite LLCS system was mainly due to the synergistic effect of MXene nanosheets and LLCS. In addition, the iron oxides generated by the reaction during the friction process also promote lubrication. It is believed that the current work provides an alternative method for the development of MXene/LLCS-lubricating materials.