Jump to main content
Jump to site search

Ionized water confined in graphene nanochannels

Author affiliations


When confined between graphene layers, water behaves differently from the bulk and exhibits unusual properties such as fast water flow and ordering into a crystal. The hydrogen-bonded network is affected by the limited space and by the characteristics of the confining walls. The presence of an extraordinary number of hydronium and hydroxide ions in narrow channels has the following effects: (i) they affect water permeation through the channel, (ii) they may interact with functional groups on the graphene oxide surface and on the edges, and (iii) they change the thermochemistry of water, which are fundamentally important to understand, especially when confined water is subjected to an external electric field. Here we study the physical properties of water when confined between two graphene sheets and containing hydronium and hydroxide. We found that: (i) there is a disruption in the solvation structure of the ions, which is also affected by the layered structure of confined water, (ii) hydronium and hydroxide occupy specific regions inside the nanochannel, with a prevalence of hydronium (hydroxide) ions at the edges (interior), and (iii) ions recombine more slowly in confined systems than in bulk water, with the recombination process depending on the channel height and commensurability between the size of the molecules and the nanochannel height – a decay of 20% (40%) in the number of ions in 8 ps is observed for a channel height of h = 7 Å (bulk water). Our work reveals distinctive properties of water confined in a nanocapillary in the presence of additional hydronium and hydroxide ions.

Graphical abstract: Ionized water confined in graphene nanochannels

Back to tab navigation

Publication details

The article was received on 06 Jan 2019, accepted on 18 Mar 2019 and first published on 22 Mar 2019

Article type: Paper
DOI: 10.1039/C9CP00075E
Citation: Phys. Chem. Chem. Phys., 2019, Advance Article

  •   Request permissions

    Ionized water confined in graphene nanochannels

    B. R. H. de Aquino, H. Ghorbanfekr-Kalashami, M. Neek-Amal and F. M. Peeters, Phys. Chem. Chem. Phys., 2019, Advance Article , DOI: 10.1039/C9CP00075E

Search articles by author