Abstract
In this study, we fabricated and characterized vertical molecular junctions consisting of self-assembled monolayers of benzenedithiol (BDT) with a p-doped multilayer graphene electrode. The p-type doping of a graphene film was performed by treating pristine graphene (work function of ∼4.40 eV) with trifluoromethanesulfonic (TFMS) acid, producing a significantly increased work function (∼5.23 eV). The p-doped graphene-electrode molecular junctions statistically showed an order of magnitude higher current density and a lower charge injection barrier height than those of the pristine graphene-electrode molecular junctions, as a result of interface engineering. This enhancement is due to the increased work function of the TFMS-treated p-doped graphene electrode in the highest occupied molecular orbital-mediated tunneling molecular junctions. The validity of these results was proven by a theoretical analysis based on a coherent transport model that considers asymmetric couplings at the electrode-molecule interfaces.
Original language | English |
---|---|
Pages (from-to) | 42043-42049 |
Number of pages | 7 |
Journal | ACS Applied Materials and Interfaces |
Volume | 9 |
Issue number | 48 |
DOIs | |
Publication status | Published - 2017 Dec 6 |
Keywords
- benzenedithiol (BDT)
- charge transport
- coherent transport model
- graphene doping
- interface engineering
- molecular electronics
- self-assembled monolayer
- transition voltage spectroscopy
ASJC Scopus subject areas
- Materials Science(all)