Enhanced ordering reduces electric susceptibility of liquids confined to graphene slit pores.
The behaviours of a range of polar and non-polar organic liquids (acetone, ethanol, methanol, N-methyl-2-pyrrolidone (NMP), carbon tetrachloride and water) confined to 2D graphene nanochannels with thicknesses in the range of 4.5 Å to 40 Å were studied using classical molecular dynamics and hybrid density functional theory. All liquids were found to organise spontaneously into ordered layers parallel to the confining surfaces, with those containing polar molecules having their electric dipoles aligned parallel to such surfaces. In particular, monolayers of NMP showed remarkable in-plane ordering and low molecular mobility, suggesting the existence of a previously unknown 2D solid-like phase. Calculations for polar liquids showed dramatically reduced static permittivities normal to the confining surfaces; these changes are expected to improve electron tunnelling across the liquid films, modifying the DC electrical properties of immersed assemblies of carbon nanomaterials.
Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom.
Jeronimo
J
Terrones
Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom.
Patrick J
PJ
Kiley
Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom.
James A
JA
Elliott