Thermo-osmotic flows: toward hot or cold?

Post date: Nov 22, 2017 8:20:31 PM

Li, Samy and Laurent have just published a paper entitled "What controls thermo-osmosis? Molecular simulations show the critical role of interfacial hydrodynamics" in Physical Review Letters. Waste heat harvesting is one of the greatest challenges of our society. Nanofluidic systems could play a role thanks to thermo-osmotic flows, generated at surfaces by temperature gradients. In this article, the authors use atomistic simulations to explore the underlying molecular mechanisms, and understand the effect of the wetting properties of the liquid on the solid surfaces. They show the critical role of interfacial hydrodynamics, which can reverse the direction of the flow, and strongly amplify it. In particular, they predict giant thermos-osmotic flows at the water-graphene interface. These theoretical results open many perspectives for the efficient generation of flows using waste heat, with could be applied for instance to sea water desalination.