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Register a new userDramatic effect of a transverse electric field on frictional properties of graphene
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Zhao Wang
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We study the influence of transverse electric fields on the interfacial forces between a graphene layer and a carbon nanotube tip by means of atomistic simulations, in which a Gaussian regularized charge-dipole potential is combined with classical force fields. A significant effect of the field-induced electric charge on the normal force is observed. The normal pressure is found to be sensitive to the presence of a transverse electric field, while the friction force remains relatively invariant for the here-used field intensities. The contact can even be turned to have a negative coefficient of friction in a constant-distance scenario when the field strength reaches a critical value, which increases with decreasing tip-surface distance. These results shed light on how the frictional properties of nanomaterials can be controlled via applied electric fields.
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