Twin Octagonal‐Graphene: A New Two‐Dimensional Semiconducting Carbon with Intriguing Features

Earlier and recent findings on 2D carbon allotropes have advocated that a free standing 2D carbon form where atoms are distributed in different planes have mostly manifested themselves as semiconducting carbon allotropes. In this work, Twin Octagonal‐graphene is proposed which is a hybridized 2D semiconducting form of carbon in symmetry class where the carbon atoms are distributed in three planes. This material satisfies all stability conditions and expresses direct band gap of 1.14 eV in its band structure at the gamma point in the first Brillouin zone. The material belongs to the class of elastically soft and anisotropic category. It is observed that the material can uniquely undergo change in its electronic behavior under strain from semiconducting to metallic to semimetallic form within a range of equi‐biaxial strain without undergoing any change in its morphology. However, further increase in strain transforms the material into another stable direct semiconductor of different morphology within 10% compressive strain. The hole mobility of the original material under the acoustic–phonon approximation has been found to be ten times higher than the electron mobility of this material. The optical properties of the material for different polarization render extremely interesting features. The material has potential application in electronics, sensor, infrared detectors, night vision devices, thermophotovoltaics and optical materials.