Excellent corrosion inhibition and lubrication properties of carbon dot-based ionic liquids as water-based additives

Ionic liquids (ILs) and carbon dots (CDs) have gained more attention as versatile materials. Noticeably, the carbon dot-based ionic liquids (CDILs), a novel ionic combination of the two materials, will be endowed with superior performance and promote the application of CDs in fields of corrosion inhibition and lubrication. In this work, three CDILs with different alkyl chain numbers were synthesized as water-based multifunctional additives. CDILs show excellent corrosion inhibition effect in corrosive aqueous solution and superior lubricating behavior in water. Interestingly, CDILs with medium numbers of alkyl chains in cationic moiety exhibits optimal corrosion inhibition and lubrication performance. Both the physical adsorption of CDILs and the structures of cations influence the quality of adsorption and lubricating film.