Transport properties of Ag decorated zigzag graphene nanoribbons as a function of temperature: a density functional based tight binding molecular dynamics study

The systemic study of the electronic transport (ET) properties of transition metal (TM) functionalized graphene was done with the aid of self-consistent charge density functional based tight binding (DFTB) method. Results show that among the TM considered, Silver metal adsorbed in the surface of graphene and its lower dimensional analogue zigzag graphene nanoribbon (ZGNR) can open its gapless bandstructure. This can be attributed to the breaking of bond and inversion symmetry. Further, the inherent effect of phonons (lattice vibrations) on the transport properties Ag-adsorbed ZGNR were investigated based on DFTB molecular dynamics (MD) simulation. Results show that excellent ET properties can be attributed to the Ag and ZGNR interaction. In addition, due to the unceasing lattice vibration of the Ag/ZGNR, the ET changes. Knowledge about the quantum of vibration at temperature T is quite important to elucidate its role governing the resulting ET. As the phonon having shorter wave length significantly increases at elevated temperatures, the corresponding forward bias voltage across the Ag/ZGNR increases. There is an increase in the conductance of vibrating Ag/ZGNR at elevated temperatures. A single-gated field effect transistor based on Ag-adsorbed ZGNR can act as a potential semiconductor for modern electronic applications.