SSLiP · Scaling-up SuperLubricity into Persistence

Friction between moving parts and the associated wear are estimated to be directly responsible for 25% of the world's energy consumption. SSLiP seeks to establish a radically new way to drastically reduce friction, with potentially enormous technological and societal impact. The driving concept is structural superlubricity, extremely low friction that takes place at a lattice misfit between clean, flat, rigid crystalline surfaces. Structural superlubricity is currently a lab curiosity limited to micrometer scale and laboratory times. SSLiP will bring this to the macroscale to impact real-life products. The key idea is the use of tribo-colloids: colloidal particles coated in 2D materials, that will produce a dynamic network of superlubric contacts. Structural incompatibility between arrays of colloids allows us to replicate the low friction on bigger length scales and overcome the statistical roughness of real surfaces. We will leverage our breakthrough result to regenerate the 2D coatings themselves during sliding. Through careful design of these coatings, carrier fluid, and the mechanical properties of the core particles, the chemistry of sliding and collective behaviour of the colloids can be controlled. Synthesis and experiments of individual contacts will be combined with visualisation of colloid dynamics during sliding on larger scales and in-site chemical characterisation. These will be combined with multiscale simulations and theory to bridge the different length scales into a coherent framework. The developed ultra-low friction technology will drastically reduce loss of energy, for example in passenger cars (responsible for around 2 billion tonnes of CO2 per year) and increase the lifetime of parts. It will also enable radically new technologies that are impossible with current lubrication, thus paving the way for e.g. much higher writing speeds in harddisks, where the writing tip will be able to move in full contact with the disk.