Surface chemistry of graphene and graphene oxide: A versatile route for their dispersion and tribological applications

• Published in: Advances in colloid and interface science Vol. 283; p. 102215
• Main Authors: Chouhan, Ajay, Mungse, Harshal P., Khatri, Om P.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2020
• Subjects: Dispersion; Graphene; Lubrication; Materials chemistry; Surfaces and interfaces; Surfaces and interfaces; Lubrication; Graphene; Materials chemistry; Dispersion
• ISSN: 0001-8686; 1873-3727; 1873-3727
• DOI: 10.1016/j.cis.2020.102215

Graphene, the most promising material of the decade, has attracted immense interest in a diversified range of applications. The weak van der Waals interaction between adjacent atomic-thick lamellae, excellent mechanical strength, remarkable thermal conductivity, and high surface area, make graphene a potential candidate for tribological applications. However, the use of graphene as an additive to liquid lubricants has been a major challenge because of poor dispersibility. Herein, a thorough review is presented on preparation, structural models, chemical functionalization, and dispersibility of graphene, graphene oxide, chemically-functionalized graphene, and graphene-derived nanocomposites. The graphene-based materials as additives to water and lubricating oils improved the lubrication properties by reducing the friction, protecting the contact interfaces against the wear, dissipating the heat from tribo-interfaces, and mitigating the corrosion by forming the protecting thin film. The dispersion stability, structural features, and dosage of graphene-based dispersoids, along with contact geometry, play important roles and govern the tribological properties. The chemistry of lubricated surfaces is critically reviewed by emphasizing the graphene-based thin film formation under the tribo-stress, which minimizes the wear. The comprehensive review provides variable approaches for the development of high-performance lubricant systems and accentuates the lubrication mechanisms by highlighting the role of graphene-based materials for enhancement of tribological properties. [Display omitted] •A critical review on surface chemistry, dispersion aspects, and lubrication properties of graphene-based materials.•Various approaches for chemical functionalization of graphene and graphene oxide are addressed.•Enhancement of lubrication properties by application of graphene-based dispersions is critically reviewed.•Surface chemistry of lubricated interfaces is discussed and emphasized the formation of graphene-based tribo thin film.•Insights, challenges, and opportunities of graphene-based materials for tribological applications are cautiously provided.