Issue 21, 2020

Exact matrix treatment of the statistical mechanics of adsorption of large aromatic molecules on graphene

Abstract

Experimental studies of adsorption from solution of the large aromatic molecules 1,2-dihydroxybenzene (catechol) and phenyl hydroquinone on graphene nanoplatelets show that at low coverage adsorption is followed by a transition which occurs from adsorbed molecules in flat to more vertically oriented states. Catechol adsorption isotherms exhibit 2 plateaus while phenyl hydroquinone shows 3 plateaus indicating 2 and 3 active conformers respectively participating in the adsorption process. Modelling such adsorption isotherms presents a challenge. Here, an exact matrix treatment of the statistical mechanics of a one-dimensional model of adsorption of catechol and dihydroquinone on graphene nanoplatelets is presented. The theoretical adsorption isotherms successfully reproduce all the features of both the catechol and dihydroquinone experimental adsorption isotherms. As suggested by the experimentalists, our theoretical model demonstrates that adsorbed phenyl hydroquinone molecules adopt a flat orientation at low concentrations and an edge orientation at higher coverage before eventually adopting a vertical configuration. Both catechol and phenyl hydroquinone can be described by our interconvertible monomer–dimer–trimer model. The theoretical adsorption isotherms obtained show several plateaus reflecting the types of conformer on the graphene surface.

Graphical abstract: Exact matrix treatment of the statistical mechanics of adsorption of large aromatic molecules on graphene

Article information

Article type
Paper
Submitted
15 Jan 2020
Accepted
15 May 2020
First published
16 May 2020

Phys. Chem. Chem. Phys., 2020,22, 12113-12119

Exact matrix treatment of the statistical mechanics of adsorption of large aromatic molecules on graphene

L. J. Dunne and G. Manos, Phys. Chem. Chem. Phys., 2020, 22, 12113 DOI: 10.1039/D0CP00255K

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements