The surface of graphene-like structures placed in an electric field with a strength of 1−10 V/μm is found to undergo considerable deformation. This effect is observed in both a direct field (emission current is present) and a reverse field (emission current is absent). The deformation of the surface of cathodes facilitates low-threshold electron emission. The qualitative model proposed here to explain the effect of low-energy electron emission is based on the idea of surface reconstruction and the formation of centers with negative correlation energies (negative-U centers).