Enabling ultra-low friction in lubricated contacts using tribocatalytic principles

• Applicants: Professor Dr. Martin Dienwiebel; Professor Dr. Michael Moseler
• Subject Area: Coating and Surface Technology ; Engineering Design, Machine Elements, Product Development ; Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 556195707

The research project's central objective is to explore the lubrication mechanism of sustainable lubricants in the context of liquid supralubricity. One working hypothesis is that a common mechanism for all carbon-containing lubricants is given by the the varying functional groups in the lubricant molecules. Understanding this mechanism is essential for optimizing the molecular structure of future lubricant molecules. To achieve the goals, the project involves testing reference compounds under different tribological conditions to identify conditions leading to superlubricity. The study involves a detailed examination of both the counterbodies and the lubricant solutions to analyze degradation products and friction properties. The research focuses on understanding the behavior and reactions of functional groups, such as OH, COOH, double bonds, and their impact on friction. The project also investigates the role of double bonds and their configuration (cis vs. trans) in the formation of tribolayers. In this respect, atomistic simulations represent an invaluable tool to shed light on the details of the tribofilm formation and the mechanisms behind superlubricity. Parametric studies encompassing different chemistries and tribological conditions are performed both with quantum-mechanical methods and with non-reactive MD to guide the experiments and deepen the understanding of the experiments. Furthermore, the project distinguishes between mechanical wear, which arises from abrasion or deformation, and chemical wear. The study explores the formation of tribological layers over time, influenced by mechanical load and temperature. The goal is to develop additives that can catalyze the formation of tribolayers to accelerate the process. Finally, the project will explore whether the addition of catalytically active metal salts can enable this behavior in various material pairings.

• DFG Programme: Research Grants