Phononic band gap engineering in graphene

Using ab initio and molecular dynamics simulations with semi-empirical potentials, the phonon density of states (PnDOS) of graphene with different types of defects such as substitution atoms (Si), carbon isotopes (C-12 and C-14), and vacancies was calculated. The main interest was to investigate the possibility to generate phononic band gaps (PBGs) in the PnDOS of graphene, since the derived structures may have sufficiently low thermal conductivity and find applications in improved thermoelectric materials. From all the studied defect types, the silicon substitution is the only one that creates PBGs. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4763479]