CHARGE TRANSPORT IN CONJUGATED MOLECULAR JUNCTIONS

Abstract

This Thesis studies the charge transport mechanisms in the junctions made of conjugated molecular backbones with a ferrocene head group. We used a eutectic gallium-indium (EGaIn) alloy as the top electrode to fabricate junctions and investigate their electronic properties. The effect of molecular structure, anchoring group, and the bottom electrode, are explored. The results show that Marcus Inverted Region (MIR) transport can be achieved by tuning the molecule-electrode coupling strength. The dynamics of charge transfer on the metal-molecule interfaces are also studied via synchrotron-based core-hole clock spectroscopy. The timescales of the electron transfer indicate that both the molecular structure and the bond dipole of the metal-sulphur linkage are important factors determining how fast an electron can tunnel through a molecule. The findings in this Thesis contribute to our understanding of the working principles and may inspire the design rules of future generation molecular electronic devices.