Enhanced Thermoelectric Properties of Armchair Graphene Nanoribbons with Pore Passivation

Abstract

There is a need to discover efficient thermoelectric materials that can generate electricity from waste heat and could play an important role in a global sustainable energy solution. Graphene Nanoribbons have been explored for a range of pore dimensions in order to achieve better thermoelectric performance. In this paper, we investigate the thermoelectric properties of porous armchair graphene nanoribbons by introducing hydrogen atoms as passivators at the pore surfaces. The aim of this work is to study the influence of pore passivation on the thermoelectric parameters as a function of pore geometry so as to open the possibility for an optimal pore engineering which can significantly improve the thermoelectric efficiency. The results show that the phonon thermal conductivity has a very little dependence on the pore edge passivation. An improvement in thermoelectric figure of merit is achieved due to the increased values of the power factor with consistent values of thermalconductivity. The unique thermoelectric properties of graphene nanoribbons with pore passivation suggest their great potentials for nanoscale thermoelectric applications. Within ballistic transport regime, semi-empirical extended Huckel method has been used for electrical properties while Tersoff potential has been employed for phononic calculations.