Hydrogen-Bond Ionic Conductive Gel Lubricant with Integrated Thixotropy, Lubricity, and Electrotunable Performances for Electrified Equipment

Conductive lubricants are crucial to resolving the conflict between friction wear and signal transmission in electrically powered components. Here, the excellent conductivity of ionic liquids was used to design and prepare an ionic supramolecular gel lubricant. An ionic liquid and urea-based functional groups were combined into an ionic gelator, which formed a 3D network in the base oil to form a gel that prevented migration of the base oil at the interface. The ionic supramolecular gel lubricant displayed exceptional mechanical and thermal responsiveness that facilitated reversible gel-to-sol transitions through modulation of the shear stress and temperature. Rheological tests demonstrated that the lubricant possessed high viscoelasticity, shear-thinning behavior, and creep recovery properties. The lubricant also demonstrated an exceptional tribological performance both with and without an applied electric field. Without the electric field, the lubricant reduced the friction coefficient by 42.1% and decreased the wear volume by 95.6%. Under the current-carrying conditions of 3 and 6 A, the lubricant maintained a stable friction coefficient demonstrating excellent adaptability. During carrier-driven friction tests, the ionic gelator accumulated extensively on the friction-pair surface, which resulted in enhanced adsorption properties and the formation of a denser lubricating film. The high conductivity and excellent tribological performance of the developed lubricant render it highly applicable to ensuring the stability of critical components in electronic devices and energy components.