Title: Ultra high stiffness and thermal conductivity of graphene like C3N,
Abstract: Recently, single crystalline carbon nitride 2D material with a C3N
stoichiometry has been synthesized. In this investigation, we explored the
mechanical response and thermal transport along pristine, free-standing and
single-layer C3N. To this aim, we conducted extensive first-principles density
functional theory (DFT) calculations as well as molecular dynamics (MD)
simulations. DFT results reveal that C3N nanofilms can yield remarkably high
elastic modulus of 341 GPa.nm and tensile strength of 35 GPa.nm, very close to
those of defect-free graphene. Classical MD simulations performed at a low
temperature, predict accurately the elastic modulus of 2D C3N with less than 3%
difference with the first-principles estimation. The deformation process of C3N
nanosheets was studied both by the DFT and MD simulations. Ab initio molecular
dynamics simulations show that single-layer C3N can withstand high temperatures
like 4000 K. Notably, the phononic thermal conductivity of free-standing C3N
was predicted to be as high as 815 W/mK. Our atomistic modelling results reveal
ultra high stiffness and thermal conductivity of C3N nanomembranes and
therefore propose them as promising candidates for new application such as the
thermal management in nanoelectronics or simultaneously reinforcing the thermal
and mechanical properties of polymeric materials.