Perfect proton selectivity in ion transport through two-dimensional crystals

Defect-free monolayers of graphene and hexagonal boron nitride are surprisingly permeable to thermal protons, despite being completely impenetrable to all gases. It remains untested whether small ions can permeate through the two-dimensional crystals. Here we show that mechanically exfoliated graphe...

Full description

Saved in:
Bibliographic Details
Published in:Nature communications 2019-09, Vol.10 (1), p.4243-5, Article 4243
Main Authors: Mogg, L., Zhang, S., Hao, G.-P., Gopinadhan, K., Barry, D., Liu, B. L., Cheng, H. M., Geim, A. K., Lozada-Hidalgo, M.
Format: Article
Language:English
Subjects:
147/135
147/3
639/301/299
639/766/94
639/925/918
Boron
Boron nitride
Chloride ions
Crystal defects
Crystals
Gas permeation
Gases
Graphene
Humanities and Social Sciences
Hydrochloric acid
Ion transport
Ions
Monolayers
multidisciplinary
Protons
Science
Science (multidisciplinary)
Selectivity
Two dimensional materials
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Defect-free monolayers of graphene and hexagonal boron nitride are surprisingly permeable to thermal protons, despite being completely impenetrable to all gases. It remains untested whether small ions can permeate through the two-dimensional crystals. Here we show that mechanically exfoliated graphene and hexagonal boron nitride exhibit perfect Nernst selectivity such that only protons can permeate through, with no detectable flow of counterions. In the experiments, we use suspended monolayers that have few, if any, atomic-scale defects, as shown by gas permeation tests, and place them to separate reservoirs filled with hydrochloric acid solutions. Protons account for all the electrical current and chloride ions are blocked. This result corroborates the previous conclusion that thermal protons can pierce defect-free two-dimensional crystals. Besides the importance for theoretical developments, our results are also of interest for research on various separation technologies based on two-dimensional materials. Defect-free monolayers of graphene and hexagonal boron nitride are highly permeable to thermal protons, but are impenetrable to gases. Here the authors show that mechanically exfoliated crystals exhibit perfect proton selectivity, corroborating proton transport through the bulk without atomic-scale defects.
ISSN:2041-1723
2041-1723
DOI:10.1038/s41467-019-12314-2