1
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Zhu H, Szymczyk A, Ghoufi A. Multiscale modelling of transport in polymer-based reverse-osmosis/nanofiltration membranes: present and future. DISCOVER NANO 2024; 19:91. [PMID: 38771417 PMCID: PMC11109084 DOI: 10.1186/s11671-024-04020-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 04/22/2024] [Indexed: 05/22/2024]
Abstract
Nanofiltration (NF) and reverse osmosis (RO) processes are physical separation technologies used to remove contaminants from liquid streams by employing dense polymer-based membranes with nanometric voids that confine fluids at the nanoscale. At this level, physical properties such as solvent and solute permeabilities are intricately linked to molecular interactions. Initially, numerous studies focused on developing macroscopic transport models to gain insights into separation properties at the nanometer scale. However, continuum-based models have limitations in nanoconfined situations that can be overcome by force field molecular simulations. Continuum-based models heavily rely on bulk properties, often neglecting critical factors like liquid structuring, pore geometry, and molecular/chemical specifics. Molecular/mesoscale simulations, while encompassing these details, often face limitations in time and spatial scales. Therefore, achieving a comprehensive understanding of transport requires a synergistic integration of both approaches through a multiscale approach that effectively combines and merges both scales. This review aims to provide a comprehensive overview of the state-of-the-art in multiscale modeling of transport through NF/RO membranes, spanning from the nanoscale to continuum media.
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Affiliation(s)
- Haochen Zhu
- State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, 1239 Siping Rd., Shanghai, 200092, China.
| | - Anthony Szymczyk
- CNRS, ISCR (Institut des Sciences Chimiques de Rennes) - UMR 6226, Univ Rennes, 35000, Rennes, France.
| | - Aziz Ghoufi
- CNRS, ICMPE (Institut de Chimie et des Matériaux Paris-Est) - UMR 7182, Univ Paris-East Creteil, 94320, Thiais, France.
- CNRS, IPR (Institut de Physique de Rennes) - UMR 6251, Univ Rennes, 35000, Rennes, France.
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2
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Ye K, Chin SY, Xi NL, Sharma B, Lu Y, Xue K. Characterizing the Behavior of Water Interacting with a Nano-Pore Material: A Structural Investigation in Native Environment Using Magnetic Resonance Approaches. Chemphyschem 2024:e202400053. [PMID: 38706399 DOI: 10.1002/cphc.202400053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 04/28/2024] [Accepted: 05/03/2024] [Indexed: 05/07/2024]
Abstract
The study of fluid absorption, particularly that of water, into nanoporous materials has garnered increasing attention in the last decades across a broad range of disciplines. However, most investigation approaches to probe such behaviors are limited by characterization conditions and may lead to misinterpretations. In this study, a combined MRI and MAS NMR method was used to study a nanoporous silica glass to acquire information about its structural framework and interactions with confined water in a native humid environment. Specifically, MRI was used for a quantitative analysis of water extent. While MAS NMR techniques provided structural information of silicate materials, including interactive surface area and framework packing. Analysis of water spin-spin relaxation times (T2) suggested differences in water confinement within the characterized framework. Subsequent unsuccessful delivery of paramagnetic molecule into the pores enabled a quantitative assessment of the dimensions that "bottleneck" the pores. Finally, pore sizes were derived from the paramagnetic molecular size, density function theory (DFT) simulation and characterizations on standard samples. Our result matches with Brunauer-Emmett-Teller (BET) analysis that the pore size is less than 1.3 nm. The use of a paramagnetic probe for pore size determination introduces a new approach of characterization in the liquid phase, offering an alternative to the conventional BET analysis that uses gas molecule as probes.
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Affiliation(s)
- Kai Ye
- Center of High Field NMR Spectroscopy and Imaging, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639789, Singapore
| | - Sze Yuet Chin
- Center of High Field NMR Spectroscopy and Imaging, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Nicole Lin Xi
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639789, Singapore
| | - Bhargy Sharma
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639789, Singapore
| | - Yunpeng Lu
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639789, Singapore
| | - Kai Xue
- Center of High Field NMR Spectroscopy and Imaging, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
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3
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Yang W, Yu R, Zhu S, Wang G, Zhang B, Li J, Xue S, Qi S, Zhang L, Zhao K. Artificial Hydrophilic Organic and Dendrite-Suppressed Inorganic Hybrid Solid Electrolyte Interface Layer for Highly Stable Zinc Anodes. ACS APPLIED MATERIALS & INTERFACES 2024; 16:10218-10226. [PMID: 38380613 DOI: 10.1021/acsami.3c18641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
Aqueous zinc-ion batteries (AZIBs) have gained significant attentions for their inherent safety and cost-effectiveness. However, challenges, such as dendrite growth and anodic corrosion at the Zn anode, hinder their commercial viability. In this paper, an organic-inorganic coating layer (Nafion-TiO2) was introduced to protect the Zn anode and electrolyte interface. Briefly, Nafion effectively shields against the corrosion from water molecules through the hydrophobic wall of -CF3 and guided zinc deposition from the -SO3 functional group, while TiO2 particles with a higher Young's modulus (151 GPa vs 120 GPa from Zn metal) suppress the zinc dendrite formation. As a result, with the protection of Nafion-TiO2, the symmetrical Zn∥Zn battery shows an improved cycle life of 1,750 h at 0.5 mA cm-2, and the full cell based on Zn∥MnO2 shows a long cycle life over 1,500 cycles at 1 A g-1. Our research offers a novel approach for protecting zinc metal anodes, potentially applicable to other metal anodes such as those in lithium and sodium batteries.
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Affiliation(s)
- Weijie Yang
- The Sanya Science and Education Innovation Park of Wuhan University of Technology, Sanya 572000, PR China
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, PR China
| | - Ruohan Yu
- The Sanya Science and Education Innovation Park of Wuhan University of Technology, Sanya 572000, PR China
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, PR China
| | - Shaohua Zhu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, PR China
| | - Guan Wang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, PR China
| | - Bomian Zhang
- The Sanya Science and Education Innovation Park of Wuhan University of Technology, Sanya 572000, PR China
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, PR China
| | - Jinghao Li
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, PR China
| | - Shiyan Xue
- The Sanya Science and Education Innovation Park of Wuhan University of Technology, Sanya 572000, PR China
| | - Siyuan Qi
- The Sanya Science and Education Innovation Park of Wuhan University of Technology, Sanya 572000, PR China
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, PR China
| | - Lei Zhang
- The Sanya Science and Education Innovation Park of Wuhan University of Technology, Sanya 572000, PR China
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, PR China
| | - Kangning Zhao
- Laboratory of Advanced Separations, École Polytechnique Fédérale de Lausanne, Sion 1950, Switzerland
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Unexpectedly Spontaneous Water Dissociation on Graphene Oxide Supported by Copper Substrate. J Colloid Interface Sci 2023; 642:112-119. [PMID: 37001450 DOI: 10.1016/j.jcis.2023.03.093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 03/10/2023] [Accepted: 03/15/2023] [Indexed: 03/22/2023]
Abstract
Water dissociation is of fundamental importance in scientific fields and has drawn considerable interest in diverse technological applications. However, the high activation barrier of breaking the OH bond within the water molecule has been identified as the bottleneck, even for the water adsorbed on the graphene oxide (GO). Herein, using the density functional theory calculations, we demonstrate that the water molecule can be spontaneously dissociated on GO supported by the (111) surface of the copper substrate (Copper-GO). This process involves a proton transferring from water to the interfacial oxygen group, and a hydroxide covalently bonding to GO. Compared to that on GO, the water dissociation barrier on Copper-GO is significantly decreased to be less than or comparable to thermal fluctuations. This is ascribed to the orbital-hybridizing interaction between copper substrate and GO, which enhances the reaction activity of interfacial oxygen groups along the basal plane of GO for water dissociation. Our work provides a novel strategy to access water dissociation via the substrate-enhanced reaction activity of interfacial oxygen groups on GO and indicates that the substrate can serve as an essential key to tuning the catalytic performance of various two-dimensional material devices.
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Cui R, Li S, Yu C, Zhou Y. The Evolution of Hydrogen Bond Network in Nafion via Molecular Dynamics Simulation. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c02106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Affiliation(s)
- Rui Cui
- School of Chemistry & Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Shanlong Li
- School of Chemistry & Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Chunyang Yu
- School of Chemistry & Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Yongfeng Zhou
- School of Chemistry & Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
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Ouinten ML, Szymczyk A, Ghoufi A. Molecular Dynamics Simulation Study of Organic Solvents Confined in PIM-1 and P84 Polyimide Membranes. J Phys Chem B 2023; 127:1237-1243. [PMID: 36696629 DOI: 10.1021/acs.jpcb.2c05796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Organic solvent nanofiltration (OSN) has recently proved to be a promising separation process thanks to the development of membrane materials with suitable resistance toward organic solvents. Among those materials, P84 polyimide membranes are currently the most used in OSN while PIM-1 membranes have recently attracted attention due to their high permeance in apolar solvents and alcohols. Both P84 and PIM-1 membranes have nanosized free volumes, and their separation performance is finely connected to polymer/solvent interactions. Consequently, modeling OSN membranes at the molecular scale is highly desirable in order to rationalize experimental observations and gain a deeper insight into the molecular mechanisms ruling solvent and solute permeation. A prerequisite for understanding solvent transport through OSN membranes is therefore to characterize the membrane/solvent interactions at the molecular level. For that purpose, we carried out molecular simulations of three different solvents, acetone, methanol, and toluene in contact with P84 and PIM-1 membranes. The solvent uptake by both membranes was found to be correlated to the degree of confinement of the solvent, the polymer swelling ability and polymer/solvent interactions. The translational dynamics of the solvent molecules in the PIM-1 membrane was found to be correlated with the solvent viscosity due to the relatively large pores of this membrane. That was not the case with the P84 membrane, which has a much denser structure than the PIM-1 membrane and for which it was observed that the translational dynamics of the confined solvent molecules was directly correlated to the affinity between the P84 polymer and the solvent.
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Affiliation(s)
- Mohammed-Lamine Ouinten
- Université Rennes, CNRS, IPR (Institut de Physique de Rennes) - UMR 6251F-35000Rennes, France.,Université Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes) - UMR 6226F-35000Rennes, France
| | - Anthony Szymczyk
- Université Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes) - UMR 6226F-35000Rennes, France
| | - Aziz Ghoufi
- Université Rennes, CNRS, IPR (Institut de Physique de Rennes) - UMR 6251F-35000Rennes, France
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7
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Liu Z, Wu Y, Lan F, Xie G, Zhang M, Ma C, Jia J. Improvement of permeability and antifouling performance of PVDF membranes via dopamine-assisted deposition of zwitterionic copolymer. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.130505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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8
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Development of a Soft Robotic Bending Actuator Based on a Novel Sulfonated Polyvinyl Chloride–Phosphotungstic Acid Ionic Polymer–Metal Composite (IPMC) Membrane. MEMBRANES 2022; 12:membranes12070651. [PMID: 35877854 PMCID: PMC9322641 DOI: 10.3390/membranes12070651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 06/11/2022] [Accepted: 06/22/2022] [Indexed: 12/10/2022]
Abstract
This work presents the development of a cost-effective electric-stimulus-responsive bending actuator based on a sulfonated polyvinyl chloride (SPVC)–phosphotungstic acid (PTA) ionic polymer–metal composite (IPMC), using a simple solution-casting method followed by chemical reduction of platinum (Pt) ions as an electrode. The characterizations of the prepared IPMC were performed using Fourier-transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques, Thermogravimetric analysis (TGA), and Energy-dispersive X-ray (EDX) analysis. Excellent ion-exchange capacity (IEC) and proton conductivity (PC), with values of ca. 1.98 meq·g−1 and ca. 1.6 mS·cm−1, respectively, were observed. The water uptake (WU) and water loss (WL) capacities of the IPMC membranes were measured at 25 °C, and found to have maxima of ca. 48% for 10 h, and ca. 36% at 6 V DC for almost 9 min, respectively. To analyze the actuation performance of the developed membrane, tip displacement and actuation force measurements were conducted. Tip displacement was found to be ca. 15.1 mm, whereas bending actuation was found to be 0.242 mN at 4 V DC. The moderate water loss, good proton conductivity (PC), high thermal stability, and good electrochemical properties of the developed IPMC membrane actuator position it as a cost-effective alternative to highly expensive conventional perfluorinated polymer-based actuators.
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9
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Kiyohara K, Tamura M. Transport coefficients of gel electrolytes: A molecular dynamics simulation study. J Chem Phys 2022; 156:084905. [DOI: 10.1063/5.0081118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The responses of gel electrolytes to stimuli make them useful in applications such as sensors and actuators. However, few studies have explored their transport properties from a molecular viewpoint. We studied the transport coefficients of gel electrolytes based on perfluorinated sulfonic acid using molecular dynamics simulations. The transport coefficients for electric and pressure fields, namely, the ionic conductivity, Darcy permeability, and cross coupling constant, were calculated based on Kubo’s linear response theory from the corresponding velocity correlation functions and mean square displacements. The effects of the water content of the gel electrolyte and those of the monovalent cationic species were also analyzed. The calculated transport coefficients qualitatively agree with the reported experimental results. The role of the cross coupling constants in determining the functional efficiency of gel electrolytes as pressure sensors or electroactive actuators is discussed.
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Affiliation(s)
- Kenji Kiyohara
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan
| | - Minagi Tamura
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan
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10
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Santo KP, Neimark AV. Effects of metal-polymer complexation on structure and transport properties of metal-substituted polyelectrolyte membranes. J Colloid Interface Sci 2021; 602:654-668. [PMID: 34147755 DOI: 10.1016/j.jcis.2021.06.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 11/30/2022]
Abstract
Morphological and transport properties of hydrated metal-substituted Nafion membranes doped with metal ions of different valency and coordination strength are explored using coarse-grained dissipative particle dynamics simulations. To incorporate the effects of metal-polymer complexation, we introduce a novel metal ion complexation model, in which the charged central metal ion is surrounded by dummy sites that coordinate with ligands. The model parameters are determined by matching the metal-ligand running coordination numbers and the diffusion coefficients obtained from atomistic simulations and/or experiments. The increase of valency and coordination strength is found to strongly influence both the morphology and transport characteristics of the membrane at all hydration levels. The membrane segregation into hydrophobic and hydrophilic sub-phases is affected by metal-sulphonate coordination induced crosslinking at the hydrophilic/hydrophobic interface. The simulation results indicate that the interfacial crosslinking influences the interfacial tension and thereby affect the growth and coalescence of water clusters upon the increase of hydration. Multivalent complexation hinders water and ion mobility and causes anomalous sub-diffusion and dramatic decrease of the water permeability and ionic conductivity. Our DPD model is found efficient in elucidating the mechanisms of coordination-induced cross-linking and complexation and predicting on a semi-quantitative level the morphological and transport properties of metal-substituted Nafion membranes depending on the ion valency and coordination strength. The proposed model can be further advanced and adopted for other polyelectrolyte systems, such as sulfonated block-copolymers, polysaccharide solutions and composites, and biopolymer assemblies.
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Affiliation(s)
- Kolattukudy P Santo
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey, 98 Brett Rd, Piscataway, NJ 08854, USA
| | - Alexander V Neimark
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey, 98 Brett Rd, Piscataway, NJ 08854, USA.
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11
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Ionic Liquid in Phosphoric Acid-Doped Polybenzimidazole (PA-PBI) as Electrolyte Membranes for PEM Fuel Cells: A Review. MEMBRANES 2021; 11:membranes11100728. [PMID: 34677494 PMCID: PMC8541579 DOI: 10.3390/membranes11100728] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/17/2021] [Accepted: 09/20/2021] [Indexed: 11/17/2022]
Abstract
Increasing world energy demand and the rapid depletion of fossil fuels has initiated explorations for sustainable and green energy sources. High-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) are viewed as promising materials in fuel cell technology due to several advantages, namely improved kinetic of both electrodes, higher tolerance for carbon monoxide (CO) and low crossover and wastage. Recent technology developments showed phosphoric acid-doped polybenzimidazole (PA-PBI) membranes most suitable for the production of polymer electrolyte membrane fuel cells (PEMFCs). However, drawbacks caused by leaching and condensation on the phosphate groups hindered the application of the PA-PBI membranes. By phosphate anion adsorption on Pt catalyst layers, a higher volume of liquid phosphoric acid on the electrolyte-electrode interface and within the electrodes inhibits or even stops gas movement and impedes electron reactions as the phosphoric acid level grows. Therefore, doping techniques have been extensively explored, and recently ionic liquids (ILs) were introduced as new doping materials to prepare the PA-PBI membranes. Hence, this paper provides a review on the use of ionic liquid material in PA-PBI membranes for HT-PEMFC applications. The effect of the ionic liquid preparation technique on PA-PBI membranes will be highlighted and discussed on the basis of its characterization and performance in HT-PEMFC applications.
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12
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Zhang Z, Ren J, Xu J, Meng L, Zhao P, Wang H, Wang Z. Enhanced proton conductivity of sulfonated poly(arylene ether ketone sulfone) polymers by incorporating phosphotungstic acid-ionic-liquid-functionalized metal-organic framework. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2021.119304] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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13
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Saun SB, Kim J, Hwang RY, Ahn Y, Kim D, Park DK, Lee S, Han OH. Nanometer-Scale Water Dynamics in Nafion Polymer Electrolyte Membranes: Influence of Molecular Hydrophobicity and Water Content Revisited. ACS Macro Lett 2020; 9:1013-1018. [PMID: 35648613 DOI: 10.1021/acsmacrolett.0c00173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ionic conductivity of polymer electrolyte membranes (PEMs) is an essential parameter for their device applications. In water-swollen PEMs, protons and other ions are transferred through hydrophilic channels of a few nanometers in diameter at most. Thus, optimizing the chemical and physical properties of the channels can enhance the conductivity of PEMs. However, the factors controlling the conductivity have not been completely clarified. Here, we report that measurements taken near the channel walls by a special nuclear magnetic resonance technique with ≤1 nm spatial resolution showed the largest water diffusivity when ∼80% of hydrophilic sulfonic acid groups were blocked, but the proton conductivity was low. The water diffusivity was much less affected by differences in water content. Our results provide a concept for changing the properties of PEMs and a challenge to implement the improved diffusivity in a way that enhances net ion conductivity.
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Affiliation(s)
- Seung-Bo Saun
- Western-Seoul Center, Korea Basic Science Institute, Seoul 03759, Republic of Korea
| | - JiWon Kim
- Western-Seoul Center, Korea Basic Science Institute, Seoul 03759, Republic of Korea.,Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Ryeo Yun Hwang
- Western-Seoul Center, Korea Basic Science Institute, Seoul 03759, Republic of Korea.,Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Yeonho Ahn
- School of Chemical Engineering, Sungkyunkwan University, Suwon, Gyeonggi 16419, Republic of Korea
| | - Dukjoon Kim
- School of Chemical Engineering, Sungkyunkwan University, Suwon, Gyeonggi 16419, Republic of Korea
| | - Daniel K Park
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Soonchil Lee
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Oc Hee Han
- Western-Seoul Center, Korea Basic Science Institute, Seoul 03759, Republic of Korea.,Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Republic of Korea.,Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, Republic of Korea
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