An international team of researchers from the Max Plank Institute for Polymer Research of Mainz (Germany), the Catalan Institute of Nanoscience and Nanotechnology (ICN2, Spain) and the University of Manchester (England) has found that water can interact directly with the carbon’s electrons: a quantum phenomenon that is very unusual in fluid dynamics.
A liquid, such as water, is made up of small molecules that randomly move and constantly collide with each other. A solid, in contrast, is made of neatly arranged atoms that are surrounded by a cloud of electrons. The solid and the liquid worlds are assumed to interact only through collisions of the liquid molecules with the solid’s atoms: the liquid molecules do not “see” the solid’s electrons. Nevertheless, just over a year ago, a theoretical study proposed that at the water-carbon interface, the liquid’s molecules and the solid’s electrons push and pull on each other, slowing down the liquid flow: this new effect was called quantum friction. However, the theoretical proposal lacked experimental verification.