Ultrahigh Electron Thermal Conductivity in T?Graphene, Biphenylene, and Net?Graphene

Although isolated nonhexagonal carbon rings in graphene are associated with strain relaxation and curvature, dense ordered arrangements of four-, five-, eight-membered strained carbon–carbon bonds can tile 2D planar layers. Using the Boltzmann transport equation formalism combination density functional theory calculations, how presence impacts thermal conductivity three allotropes: T-graphene (four eight rings), biphenylene (four, six, net-graphene is investigated. The phonon (?ph), which captures three-phonon, four-phonon, phonon–electron interactions, significantly lowered respect to pristine graphene. In compensation, electron (?e), electron–phonon enhanced record high values, such that room-temperature total ?total = ?ph + ?e approaches values allotropes could be interest for applications requiring energy transfer by a diffusion electrons vibrations.