Elucidating graphene-ionic liquid interfacial region: A combined experimental and computational study

Citation:

Vijayakumar, M. ; Schwenzer, B. ; Shutthanandan, V. ; Hu, J. Z. ; Liu, J. ; Aksay, I. A. Elucidating graphene-ionic liquid interfacial region: A combined experimental and computational study. Nano Energy 2014, 3 152-158.

Date Published:

Jan

ISBN Number:

2211-2855

Accession Number:

WOS:000330915300018

Abstract:

Graphene and ionic liquids are promising candidates for electrode materials and electrolytes, respectively, for modern energy storage devices such as supercapacitors. Understanding the interactions at the interfacial region between these materials is crucial for optimizing the overall performance and efficiency of supercapacitors. The interfacial region between graphene and an imidazolium-based ionic liquid is analyzed in a combined experimental and computational study. This dual approach reveals that the imidazolium-based cations mostly orient themselves parallel to the graphene surface due to pi-pi stacking interaction and form a primary interfacial layer, which is subsequently capped by a layer of anions from the ionic liquid. However, it also becomes apparent that the molecular interplay at the interfacial region is highly influenced by functional group defects on the graphene surface, in particular by hydroxyl groups. (C) 2012 Elsevier Ltd. All rights reserved.