Appropriate and precise selective sensing of highly reactive materials, especially nitroaromatic explosives, is critical for various essential security applications, such as airport security screening and strengthening homeland security. Detection of these compounds can be substantially improved with the advent of new nanoscale systems, such as two-dimensional materials. Among these materials, graphene stands out due to its excellent physical properties, attracting signifcant interest from researchers in several areas, and especially those related to real-world nanodevice applications. In this work, density functional theory along with a non-equilibrium Green’s function scattering approach has been used to examine the capability of graphene for selective sensing of single molecules. It was found that both graphene nanosheets and graphene nanodevices can be used for discriminative detection of four types of explosive molecules: 2,4-dinitrotoluene, 2,4,6-trinitrotoluene, tetryl, and picric acid. The results show that each explosive molecule affects the electronic properties of graphene differently, producing characteristic and unique features in the density of states and the electronic transport properties. In particular, the addition of explosive molecules leads, on the one hand, to the opening of an energy gap around the Fermi energy (EF) and to the emergence of peaks in the density of states, especially below the Fermi energy, and, on the other hand, to dips in the electronic transmission. Moreover, the presence of the explosive molecules also gives rise to an enhancement of the Seebeck coefficient (S), which can be used as well for discriminating between the targeted molecules. These results corroborate that it would be feasible to design and manufacture graphene-based nanosensors to discriminate between different types of compounds, particularly between explosive molecules which could have significant implications in the design of new security applications.

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