First Principles Calculation of Current-Voltage Characteristics of Defected Zigzag Graphene Nanoribons

Interesting phenomena in the electronic transport of ultra-narrow zigzag graphene nanoribbons (ZGNRs) has been demonstrated in previous works. It has been reported that although the two classes of ZGNRs, with odd and even number of transversal layers, have similar electronic structures, but they show very different I-V characteristics. In this work, we present the results of our calculations based on a combination of density functional theory and non-equilibrium Green’s function for the defected ZGNRs. The favored sites for carbon vacancies are determined according to the defect formation energies. It has been shown that the peculiar difference between the I-V characteristics of two ZGNRs classes has been removed in the presence of defects.