A fair number of semiconductors superconduct too (such as SrTiO3). The notable thing about graphene superconductivity is graphene&#x27;s electrons, not its ability to semiconduct. Because of graphene&#x27;s crystal structure, electrons propelled by a voltage will travel at constant speed, rather than accelerating. In this sense, the electrons are &#x27;massless&#x27; (photons are massless, so they always travel at the speed of light and cannot be accelerated).