Ti3C2TX derived layered MXenes as friction and wear reducing additives in lubricating oils: a detailed review.

Abstract

Friction and wear are critical factors that significantly impact the efficiency and durability of mechanical systems. The demand for improved lubricating oils capable of reducing friction and wear has spurred the exploration of advanced additives. Two-dimensional (2D) transition metal carbides, nitrides, and carbonitrides (MXenes), a new class of materials, have emerged as promising additives with exceptional tribological properties. This review paper aims to understand the usability of MXenes, specifically the ones derived from Ti3C2TX as anti-friction and antiwear additives in lubricating oils. A brief discussion is presented about the synthesis and characterization techniques employed in the synthesis of Ti3C2TX MXenes, emphasizing their unique structural and surface properties that could contribute to their tribological performance, followed by their influence on the lubricant's tribological properties is thoroughly discussed. The underlying anti-friction and antiwear mechanisms, their ability to form tribofilms on sliding surfaces, reduce direct metal-to-metal contact, and minimize wear are also highlighted. Additionally, the role of MXenes in modifying the lubricant's chemical and physical interactions with sliding surfaces is analyzed. This review also attempts to identify and address the roadblocks hindering the use of Ti3C2TX MXenes in lubricating oils, such as their aggregation tendencies, stability under extreme conditions, and potential side effects on lubricant properties along with the tentative strategies to overcome these hurdles. Relevant experimental findings in which Ti3C2TX derived 2D nano-sheets have been explored as friction and wear-reducing additives in different lubricating oils are critically assessed. Although these MXenes are claimed to be highly effective as lubricant additives in lubricating oils owing to their unique properties and versatile chemistry, further research is required to address the challenges and optimize the formulation and integration of MXenes into lubricating oils for practical implementation. This article presents a comprehensive discussion about Ti3C2TX MXenes as friction and wear-reducing additives in lubricating oils, will be crucial in understanding what has been done and needs to be done.