The science of friction on graphene
Graphene, a two-dimensional form of carbon in sheets just one atom in thick, has been the subject of widespread research, in large part because of its unique combination of strength, electrical conductivity, and chemical stability. But despite many years of study, some of graphene’s fundamental properties are still not well-understood, including the way it behaves when something slides along its surface. Now, using powerful computer simulations, researchers at MIT and elsewhere have made significant strides in understanding that process, including why the friction varies as the object sliding on it moves forward, instead of remaining constant as it does with most other known materials. The findings are presented this week in the journal Nature, in a paper by Ju Li, professor of nuclear science and engineering and of materials science and engineering at MIT, and seven others at MIT, the University of Pennsylvania, and universities in China and Germany. Graphite, a bulk material...