Creating graphene geometry diodes through fluorination: First-principles studies

Using density functional theory in combination with Green's functional formalism we study the possibility of creating geometry diodes from monolayer graphene through spatial fluorination. The system shows better diode properties (i.e, larger current rectification and smaller differential resistance) as compared to our reference sample, where the asymmetry is created by direct structural nano-patterning. Depending on the value of the bias voltage, current rectification more than one order of magnitude can be obtained in the fluorinated system. The obtained results are explained in terms of nano-scale charge localization in the system as revealed in the analysis of transmission eigenstates and molecular projected self-consistent Hamiltonian states. These findings show the potential of fluorination in creating graphene geometry diodes for practical applications.