Novel formulations for scalable multilayer nanoporous graphene-based membranes for use in efficient water detoxification revisited

Gupta, Sanju; Henson, Alex; Evans, Brendan

doi:10.5004/dwt.2019.24688

Cited by 4 publications

(11 citation statements)

References 53 publications

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“…This effect becomes significant for lower concentration due to increase of Debye length. This finding agrees with experiments for alkali ion and chlorine ion diffusion in nanopores and with models based on size exclusion effect [13,14] (ii) second, when ethanol-treated membrane is impregnated with GA, ion diffusion recovers from the level measured for the non-impregnated membrane. The primary interpretation of this outcome is that GA strongly influences the effective ion diffusion when there is a critical loading of proteins inside the nanopores.…”

Section: Ion Transport Through Artificial Biological Ion Channel Memb...supporting

confidence: 89%

“…Then, 1.5 μM of GA in methanol was created. Dilution of 1.5 μM to 20 mL of 100 nM was achieved by adding 18.7 mL of methanol to 1.3 mL of 1.5 μ M GA. Graphene oxide (GO) was prepared following modified Hummers' method [14,39]. The hydroxyl, ester, and epoxide groups were converted to carboxylic (-COOH) group by treating as-prepared GO with appropriate chemicals.…”

Section: Preparation Of Track-etched Polymer Membrane and Materials D...mentioning

confidence: 99%

“…We also report the permeability and salt rejection of the membranes examined by evaluating the selected mono-and di-valent (NaCl, KCl, CaCl2, and MgCl2) chloride electrolytes. To minimize the concentration polarization effect on the retention performance, the feed solution was continuously stirred at 500 rpm during the dead-end filtration (Model HP4750, Sterlitech Inc., Auburn, WA) described in detail elsewhere [14]. The retention performance of membranes for the electrolyte ions were calculated using equation:…”

Section: Membrane Performance (Ion Transport/diffusion Tests and Uv-v...mentioning

confidence: 99%

“…Current water purification technologies include reverse osmosis (RO), nanofiltration (NF), and recently resurged forward osmosis (FO) processes that utilize membranes to achieve significant removal of contaminants [9,10,11,12,13]. RO is a pressuredriven process where unwanted impurities is forced through a semi-permeable membrane, selectively transporting monovalent ions (Na + , K + , Cl − ) and water molecules while rejecting 2 multivalent ions, dissolved organic compounds and micro-organisms (e.g., bacteria) [3,14,15,16]. The membranes used are based on conventional thin film polymer (polyamide; PA, cellulose acetate; CA, polysulfone; PS), polymeric composites, and ceramics that have salient advantages such as good separation capability, structural stability (mechanical robustness), anti-biofouling, and wide pH tolerance [17,18,19].…”

Section: Introductionmentioning

confidence: 99%

“…With reasonable understanding of such complex systems, the next step is to design better membranes and develop understanding of membrane processes. To this end, graphene oxide, GO (graphene layer with oxygen/hydroxyl functional groups at basal and edge planes) is an emergent material for solid-state membrane and selective ion transport through stacked GO layers with holes in the basal plane and interlayer spacing has been reported [14,37,38,39]. It was first realized by molecular dynamic (MD) simulations where nanopores were theorized on the graphene monolayer (basal plane) to allow water to permeate while rejecting or retaining undesired substances proficiently [24,24,40].…”

Section: Introductionmentioning

confidence: 99%

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Bioinspired and Biomimetic Membranes Using Ion Channel Pro-teins and Designer Peptides Conjugated With Graphene Oxide for Selective Ion Transport

Gupta¹,

Robinson²,

Evans³

2023

Preprint

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Recent advances in synthetic membranes allow their use in fields as diverse as food and agriculture, biotechnology, industrial wastewater treatment, and potable water production. Among the newly developed technologies, nanofiltration for liquids and more particularly for desalination of seawater or saline aquifers are actively pursued. However, current solid-state membranes performance is limited, which calls for the development of novel formulations for membranes offering both high permeability (ion and water flux) and ion differentiation (selectivity), usually considered antagonist features. We report the development of hybrid nanoporous membranes made of solid-state polymeric carbonate track-etched (PCTE) thin films in which biological ion channels such as Gramicidin A (GA), alpha-hemolysin (α-HL), and outer-membrane protein F (OmpF) aquaporin are confined and graphene oxide (GO) conjugated cobalt ion selective binding peptide motifs (Copep) are adsorbed, referring as bioinspired and biomimetic approaches, respectively. These solid-state nanoporous membranes are attracting widespread attention since they offer scalability, mechanical robustness, selectivity, controlled pore dimension and shape, for water sustainability. The ion permeability, ion diffusion coefficient and selective ion recognition are evaluated via nanofiltration, cell diffusion kinetics, and UV-Visible absorption spectroscopy to gain insights into the role of key performance parameters including effective ion confinement in track-etched pores, rich surface chemistry, and peptide-induced channel for selective ion transport. These findings provide new avenues for artificial ion channels by synergistic combination of eco-friendly material design such as GO enabled by bio-molecular recognition chemistry.

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Section: Ion Transport Through Artificial Biological Ion Channel Memb...supporting

confidence: 89%

Section: Preparation Of Track-etched Polymer Membrane and Materials D...mentioning

confidence: 99%

Section: Membrane Performance (Ion Transport/diffusion Tests and Uv-v...mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Bioinspired and Biomimetic Membranes Using Ion Channel Pro-teins and Designer Peptides Conjugated With Graphene Oxide for Selective Ion Transport

Gupta¹,

Robinson²,

Evans³

2023

Preprint

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Desalination Performance in Janus Graphene Oxide Channels: Geometric Asymmetry vs Charge Polarity

Li,

Zhang,

2024

ACS Appl. Mater. Interfaces

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Improving the desalination performance of membranes is always in the spotlight of scientific research; however, Janus channels with polarized surface charge as nanofiltration membranes are still unexplored. In this work, using molecular dynamics simulations, we demonstrate that Janus graphene oxide (GO) channels with appropriate geometry and surface charge can serve as highly efficient nanofiltration membranes. We observe that the water permeability of symmetric Janus GO channels is significantly superior to that of asymmetric channels without sacrificing much ion rejection, owing to weakened ion blockage and electrostatic effects. Furthermore, in symmetric Janus GO channels, the transport of water and ions is sensitive to the charge polarity of the channel inner surface, which is realized by tuning the ratio of cationic and anionic functionalization. Specifically, with the increase in cationic functionalization, the water flux decreases monotonously, while ion rejection displays an interesting maximum behavior that indicates desalination optimization. Moreover, the trade-off between water permeability and ion rejection suggests that the Janus GO channels have an excellent desalination potential and are highly tunable according to the specific water treatment requirements. Our work sheds light on the key role of channel geometry and charge polarity in the desalination performance of Janus GO channels, which paves the way for the design of novel desalination devices.

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Control one-dimensional length of rectangular pore on graphene membrane for better desalination performance

Chen¹,

Ding²,

Li³

et al. 2022

Nanotechnology

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At present, there is a general contradiction between permeability and selectivity of reverse osmosis (RO) membranes for desalination; a membrane with higher water permeability will give a lower salt rejection or selectivity, and vice versa. In this work, single-layer nanoporous graphene is used as RO membrane to investigate the effects of pore shape to reduce this contradiction by molecular dynamics (MD) simulations. Two kinds of pores (round and rectangular pores) with different sizes are simulated. For round pore, although the water permeability increases with the increase of the pore size, the salt rejection rate drops rapidly. For rectangular pore, reasonable designed pore structure can achieve improved water permeability and high salt rejection of graphene membrane by keeping one-dimensional length (i.e., the width) of the pore less than the size of the hydrated ions and increasing the other dimensional length. The restriction of one dimension can prevent the passage of hydrated ions through the pore effectively. This “one-dimensional restriction” provides a simple strategy for designing RO membrane with variable pore structures to obtain a better desalination performance.

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Novel formulations for scalable multilayer nanoporous graphene-based membranes for use in efficient water detoxification revisited

Cited by 4 publications

References 53 publications

Bioinspired and Biomimetic Membranes Using Ion Channel Pro-teins and Designer Peptides Conjugated With Graphene Oxide for Selective Ion Transport

Bioinspired and Biomimetic Membranes Using Ion Channel Pro-teins and Designer Peptides Conjugated With Graphene Oxide for Selective Ion Transport

Desalination Performance in Janus Graphene Oxide Channels: Geometric Asymmetry vs Charge Polarity

Control one-dimensional length of rectangular pore on graphene membrane for better desalination performance

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