Electronic Properties of Molecular-Adsorbed Monolayer Graphene

The band structure and density of state (DOS) of freestanding monolayer graphene with molecular adsorption were simulated by using Quantum ESPRESSO (QE) and a quantum chemical simulation tool called DV-Xα. It was found that the Dirac cone structure in band structure collapsed as the carbon monoxide molecules approached graphene surface. The density of states also confirmed the change of band structure. The adsorption of large molecules such as glucose on graphene surface was also investigated. Glucose adsorption resulted in the appearance of a band gap as in the case of carbon monoxide adsorption. The results from this study shows that DV-Xα can be used along with other DFT tools such as QE to study the sensitivity and selectivity of changes in density of states, which may contribute to the development of molecular sensors.