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Chemical control over the energy-level alignment in a two-terminal junction.

ABSTRACT: The energy-level alignment of molecular transistors can be controlled by external gating to move molecular orbitals with respect to the Fermi levels of the source and drain electrodes. Two-terminal molecular tunnelling junctions, however, lack a gate electrode and suffer from Fermi-level pinning, making it difficult to control the energy-level alignment of the system. Here we report an enhancement of 2 orders of magnitude of the tunnelling current in a two-terminal junction via chemical molecular orbital control, changing chemically the molecular component between a stable radical and its non-radical form without altering the supramolecular structure of the junction. Our findings demonstrate that the energy-level alignment in self-assembled monolayer-based junctions can be regulated by purely chemical modifications, which seems an attractive alternative to control the electrical properties of two-terminal junctions.

SUBMITTER: Yuan L

PROVIDER: S-EPMC4963472 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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Chemical control over the energy-level alignment in a two-terminal junction.

Yuan Li L Franco Carlos C Crivillers Núria N Mas-Torrent Marta M Cao Liang L Sangeeth C S Suchand CSS Rovira Concepció C Veciana Jaume J Nijhuis Christian A CA

Nature communications 20160726

The energy-level alignment of molecular transistors can be controlled by external gating to move molecular orbitals with respect to the Fermi levels of the source and drain electrodes. Two-terminal molecular tunnelling junctions, however, lack a gate electrode and suffer from Fermi-level pinning, making it difficult to control the energy-level alignment of the system. Here we report an enhancement of 2 orders of magnitude of the tunnelling current in a two-terminal junction via chemical molecula ...[more]

PMID: 27456200

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