Water transport through subnanopores in the ultimate size limit: Mechanism from molecular dynamics

Jiyu Xu, Chongqin Zhu, Yifei Wang, Hui Li, Yongfeng Huang, Yutian Shen, Joseph S. Francisco, Xiao Cheng Zeng, Sheng Meng

Research output: Contribution to journalArticle

3 Scopus citations

Abstract

Ab initio and classical molecular dynamics simulations show that water can flow through graphdiyne—an experimentally fabricated graphene-like membrane with highly dense (2.4 × 10 18 pores/m 2 ), uniformly ordered, subnanometer pores (incircle diameter 0.57 nm and van der Waals area 0.06 nm 2 ). Water transports through subnanopores via a chemical-reaction-like activated process. The activated water flow can be precisely controlled through fine adjustment of working temperature and pressure. In contrast to a linear dependence on pressure for conventional membranes, here pressure directly modulates the activation energy, leading to a nonlinear water flow as a function of pressure. Consequently, high flux (1.6 L/Day/cm 2 /MPa) with 100% salt rejection efficiency is achieved at reasonable temperatures and pressures, suggesting graphdiyne can serve as an excellent membrane for water desalination. We further show that to get through subnanopores water molecule must break redundant hydrogen bonds to form a two-hydrogen-bond transient structure. Our study unveils the principles and atomistic mechanism for water transport through pores in ultimate size limit, and offers new insights on water permeation through nanochannels, design of molecule sieving and nanofluidic manipulation.

Original languageEnglish (US)
Pages (from-to)587-592
Number of pages6
JournalNano Research
Volume12
Issue number3
DOIs
StatePublished - Mar 1 2019

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Keywords

  • desalination
  • graphdiyne
  • molecular dynamics
  • subnanopore
  • water transport

ASJC Scopus subject areas

  • Materials Science(all)
  • Electrical and Electronic Engineering

Cite this

Xu, J., Zhu, C., Wang, Y., Li, H., Huang, Y., Shen, Y., Francisco, J. S., Zeng, X. C., & Meng, S. (2019). Water transport through subnanopores in the ultimate size limit: Mechanism from molecular dynamics. Nano Research, 12(3), 587-592. https://doi.org/10.1007/s12274-018-2258-7