Discriminating sensing of explosive molecules using graphene-boron nitride-graphene heteronanosheets.

Since the synthesis of graphene-boron nitride heterostructures, their interesting electronic properties have attracted huge attention for real-world nanodevice applications. In this work, we combined density functional theory (DFT) with a Green's function approach to examine the potential of graphene-boron nitride-graphene heteronanosheets (h-NSHs) for discriminating single molecule sensing. Our result demonstrates that the graphene-boron nitride-graphene (h-NSHs) can be used for discriminate sensing of the 2,4-dinitrotoluene (DNT), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), pentaerythritol tetranitrate (PENT), and 2,4,6-trinitrotoluene (TNT) molecules. We demonstrate that as the length of the BN region increases, the sensitivity of the heteronanosheets to the presence of these explosive substances increases.

Electronic properties of linear carbon chains: resolving the controversy.

Literature values for the energy gap of long one-dimensional carbon chains vary from as little as 0.2 eV to more than 4 eV. To resolve this discrepancy, we use the GW many-body approach to calculate the band gap E(g) of an infinite carbon chain. We also compute the energy dependence of the attenuation coefficient ß governing the decay with chain length of the electrical conductance of long chains and compare this with recent experimental measurements of the single-molecule conductance of end-capped carbon chains. For long chains, we find E(g) = 2.16 eV and an upper bound for ß of 0.21 Å(-1).