Tunable, Strain-Controlled Nanoporous MoS₂ Filter for Water Desalination

Abstract

The deteriorating state of global fresh water resources represents one of the most serious challenges that scientists and policymakers currently face. Desalination technologies, which are designed to extract potable water from the planet's bountiful stores of seawater, could serve to alleviate much of the stress that presently plagues fresh water supplies. In recent decades, desalination methods have improved via water-filtering architectures based on nanoporous graphene filters and artificial membranes integrated with biological water channels. Here, we report the auspicious performance (in simulations) of an alternative nanoporous desalination filter constructed from a MoS2 nanosheet. In striking contrast to graphene-based filters, we find that the "open" and "closed" states of the MoS2 filter can be regulated by the introduction of mechanical strain, yielding a highly tunable nanopore interface. By applying lateral strain to the MoS2 filter in our simulations, we see that the transition point between "open" and "closed" states occurs under tension that induces about 6% cross-sectional expansion in the membrane (6% strain); the open state of the MoS2 filter demonstrates high water transparency and a strong salt filtering capability even under 12% strain. Our results thus demonstrate the promise of a controllable nanoporous MoS2 desalination filter, wherein the morphology and size of the central nanopore can be precisely regulated by tensile strain. These findings support the design and proliferation of tunable nanodevices for filtration and other applications.

Nanoporous two-dimensional MoS2 membranes for fast saline solution purification

“…40 They found that the diameter of pore is too small to allow the water molecule pass through, unless the mechanical strain is applied. 40 Water-MoS 2 LJ parameters were obtained by applying the Lorentz-Berthelot mixing rules, 39 Although nanopore in MoS 2 membrane with only Mo-or S-terminators is energetically favorable, the dimension of nanopore is difficult in calculating.…”

“…32 Meanwhile, the MoS 2 membrane has superior elasticity and flexibility, 33,34 and a monolayer of MoS 2 is stronger than the bulk crystal. 38,39 Recently, Li et al 40 35,36,37,38 Past studies have already shown that nanoporous MoS 2 membrene has potential application in DNA sequencing.…”

Mechanosensitive Ion Permeation across Subnanoporous MoS2 Monolayers

“…Molecular dynamics (MD) simulations of tensile strain applied to a non-ionconducting pore in MoS 2 have shown that it was impermeable to water for small strains and highly permeable to water above a strain of 6% while maintaining robust ion rejection. 16 Given its ability to sustain strains of up to 6 to 11% before breaking, 17 MoS 2 overall is a very promising material for straincontrolled permeation in liquid environments. Here we propose the use of tensile strain to tune the ion permeation properties of sub-nanoporous single-layer MoS 2 membranes.…”

Design, Synthesis and High HER Performances of 3D Ni/Mo Sulfide on Ni Foam

“…[19][20][21] Its HER performance is far behind that of Pt-based catalysts, however, because the poor conductivity and the fact that the active sites are mainly concentrated on Mo edges with only fewer ones on the plane. Many approaches have been attempted to improve the catalytic activity of MoS 2 , such as morphology and structure regulation to expose more active sites, [22][23][24] introducing defects as active sites, and compositing with other materials to accelerate electron transport. [25] Ni 3 S 2 is another transition metal sulfide material that is a potential candidate as an alternative to noble-metal materials awing to its resource's abundance, high conductivity and low cost.…”