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arXiv · 1507.01680

Observation of Electrically Tunable van der Waals Interaction in Graphene-Molecule Complex

Manoharan Muruganathan·Jian Sun·Tomonori Imamura·Hiroshi Mizuta
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Abstract

van der Waals (vdW) interaction plays a fundamental role in the surface-molecules related phenomena. Tuning of the correlated charge fluctuation in the vdW complex is a plausible way to modulate the molecules interaction at the atomic surface. We report vdW interaction tunability of the graphene-CO$_2$ complex by combining the first principle calculations with the vdW exchange correlation density functionals and the time evaluation measurements of CO$_2$ molecules adsorption/desorption on graphene under an external electric field. The field-dependent charge transfer within the complex unveils the controllable tuning of CO$_2$ from acceptor to donor. Meanwhile the configuration of the adsorbed molecule - the equilibrium distance from graphene and O-C-O bonding angle - is modified accordingly. The range of electrical tunability is a unique feature for each type of molecules.

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Manoharan Muruganathan, Jian Sun, Tomonori Imamura, Hiroshi Mizuta. 2015-07-07. Observation of Electrically Tunable van der Waals Interaction in Graphene-Molecule Complex. https://doi.org/10.1021/acs.nanolett.5b03653

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