Charge Transport in Pentacene-Graphene Nanojunctions

TL;DR

This study explores how the electronic properties of graphene, especially edge states, influence charge transport in pentacene-graphene nanojunctions, revealing the impact of molecular and chemical modifications on conductance.

Contribution

It provides a detailed analysis of charge transport mechanisms in pentacene-graphene nanojunctions using DFT and Landauer formalism, highlighting the role of graphene edge states and chemical modifications.

Findings

Edge states in zigzag graphene electrodes create additional transport channels.

Molecular linker groups and chemical substitutions significantly affect conductance.

Transport properties are sensitive to molecule-lead coupling and energy level alignment.

Abstract

We investigate charge transport in pentacene-graphene nanojunctions employing density functional theory (DFT) electronic structure calculations and the Landauer transport formalism. The results show that the unique electronic properties of graphene strongly influence the transport in the nanojunctions. In particular, edge states in graphene electrodes with zigzag termination result in additional transport channels close to the Fermi energy which deeply affects the conductance at small bias voltages. Investigating different linker groups as well as chemical substitution, we demonstrate how the transport properties are furthermore influenced by the molecule-lead coupling and the energy level lineup.