Advances in ionogels for proton-exchange membranes

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 921, P. 171099 - 171099

Published: Feb. 21, 2024

Language: Английский

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Exceptional Anhydrous Proton Conduction in Covalent Organic Frameworks

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(26), P. 18151 - 18160

Published: June 22, 2024

Covalent organic frameworks (COFs) offer an irreplaceable platform for mass transport, as they provide aligned one-dimensional channels pathways. Especially, proton conduction is of great scientific interest and technological importance. However, unlike under humidity, anhydrous remains a challenge, it requires robust materials proceeds harsh conditions. Here, we report exceptional in stable crystalline porous COFs by integrating neat phosphoric acid into the to form extended hydrogen-bonding networks. The networks pores are stabilized hierarchical multipoint multichain interactions with 3D channel walls. We synthesized five hexagonal that possess different pore sizes, which gradually tuned from micropores mesopores. Remarkably, mesoporous high volume exhibit conductivity 0.31 S cm–1, marks highest among all examples reported COFs. observed dependent on volume, size, content acid. Increasing improves exponential fashion. changing 0.41 1.60 cm3 g–1 increases 1150-fold. Interestingly, size increases, activation energy barrier decreases linear mode. mesopores enable fast hopping across channels, while follow sluggish vehicle conduction. Experiments tuning loading contents revealed well-developed network critical

Language: Английский

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Inherent Ultrahigh Proton Conductivity of Two Highly Stable COOH-Functionalized Hafnium-Based Metal–Organic Frameworks

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 5, 2025

Although there has been some recent interest in the proton conductivity (σ) of highly stable carboxyl metal–organic frameworks (MOFs) made tetravalent metal ions, given their potential applications fuel cells and electrochemical sensing, research on MOFs constructed by hafnium(IV) ions needs to be expanded significantly. Based this, we used two common easily prepared phenylpoly(carboxylic acid) ligands, 1,2,4-phenyltricarboxylic acid 1,2,4,5-phenyltetracarboxylic acid, react with hafnium tetrachloride, respectively, creating porous hafnium(IV)-based MOFs, UiO-66-COOH-Hf (1) UiO-66-(COOH)2-Hf (2), same structure as UiO-66-Hf but different numbers free carboxylic groups. A series stability assays revealed that had excellent structural rigidity, including thermal water stability. More crucially, alternating current impedance experiments demonstrate σ varies positively humidity temperature, reaching up 10–3 S·cm–1 (1: 2.83 × 2: 4.35 S·cm–1) under right conditions (98% relative 100 °C). The latter roughly doubles former, which is due difference number groups, confirmed analysis conduction mechanism investigation. high intrinsic lays a solid foundation for future application affords new inspiration developing high-performance proton-conductive materials.

Language: Английский

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Covalent Organic Framework Membranes from Oppositely Charged Nanosheets toward Efficient Desalination

Small, Journal Year: 2024, Volume and Issue: 20(33)

Published: March 29, 2024

Fabricating covalent organic framework (COF) membranes through the pre-assembly of nanosheets with different properties may open a novel avenue to fabrication advanced 2D membranes. Herein, COF are fabricated using oppositely-charged (CONs). Negatively-charged CONs and positively-charged pre-assembled simple physical mixing, yielding an aspect ratio exceeding 10 000, which assembled into three kinds The optimal exhibit highest desalination performance permeation flux 132.66 kg m

Language: Английский

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Enhancing Proton Conductivity and Dimensional Stability of Nanofiber Proton Exchange Membranes through In Situ Growth of MOF-Modified PVDF Nanofibers

Energy & Fuels, Journal Year: 2024, Volume and Issue: 38(8), P. 7322 - 7330

Published: April 1, 2024

Proton exchange membranes often encounter challenges with proton conductivity and dimensional stability under conditions of high temperature low humidity. Incorporating proton-conductive nanofibers into the membrane fortifies its establishes extra transfer channels at interface between fibers matrix, thereby improving conductivity. This study utilized polyvinylidene fluoride (PVDF) as a base material, modified ethylenediamine to yield amine-functionalized cross-linked structures. UiO-66-NH2 UiO-66-NH2–SO3H were then grown in situ on these fibers, resultant structures integrated Nafion fabricate metal–organic framework (MOF)-modified nanofiber (NFPEMs). We examined growth MOFs their role enhancing membrane's properties. Both successfully incorporated, resulting maximum enhancement by 149.69 80.38%, respectively, compared PVDF@Nafion, MOF-loaded reaches 152.11 ms/cm 80 °C 100% relative The swelling rates also significantly reduced up 59.16 57.94%, Nafion, effectively boosting thermal stability. These improvements are attributed additional formed MOFs, contribution acid–base pairs, limitations imposed MOF porosity water molecule mobility, supportive three-dimensional network conferred PVDF. Findings from this research provide valuable guidance for design NFPEMs.

Language: Английский

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Pore size effects on high-efficiency proton conduction in three stable 3D Al-based MOFs modified with imidazole

Inorganic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(24), P. 7359 - 7368

Published: Jan. 1, 2023

Three stable porous aluminum-based MOFs 1–3 with different pore sizes were selected as an imidazole (Im) supporter and three proton conductive composites Im@1–3 prepared. Due to the size effect, σ value of Im@3 can be up 2.55 × 10 −1 S cm at 80 °C 100% RH.

Language: Английский

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Substantially Enhanced Performance of Proton Exchange Membranes by Metal–Imidazole Coordination within Metal–Organic Framework

ACS Applied Polymer Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 9, 2025

Metal–organic frameworks (MOFs) are often used as proton conductor fillers to enhance the conductivity of hybrid membranes. It is interesting but still challenging discuss influence molecular morphology and distribution carriers within MOFs on their exchange membranes (PEMs) overall performance. In this work, two types imidazole-loaded conductors were synthesized based MIL-101(Cr), with one containing free imidazole molecules other coordinating Cr-metal sites. Furthermore, series composite (CPM/IM-x CPM@IM-x, x = 1, 2, 3) fabricated using filler a cross-linked poly(vinyl alcohol) (CL-PVA) that contains both hydrophilic hydrophobic structures matrix. The CPM/IM coordinated exhibit significantly enhanced water affinity, stability, ion capacity. This mainly due improving two-phase dispersion, promoting deprotonation, facilitating low-energy-barrier transport, while CPM@IM relatively lower higher activation energy (Ea). Surprisingly, CPM/IM-2 membrane can reach up 2.7 × 10–2 S cm–1 at 85 °C 90% RH, lowest Ea 20.9 kJ/mol. remarkable performance indicates more efficient H+ transportation. Moreover, single-cell power density 89.7 mW cm–2, proving it exhibits high potential application prospects for hydrogen-based fuel cells.

Language: Английский

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Tuning hydrogen-bonding networks inside ZIF-8 membranes by weak electron donors for enhanced high-temperature proton conductivity

Science China Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 21, 2025

Language: Английский

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Fabricating MOF–GO Composites by Modulating Graphene Oxide Content to Achieve Superprotonic Conductivity

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 11, 2025

Metal–organic frameworks (MOFs) have emerged as crucial materials for proton conductivity, especially in the context of growing need alternative energy sources. Enhancing conductivity MOFs has been a major focus with one effective approach involving integration graphene oxide (GO) to form composite materials. In this study, Cr-MIL-101 MOF is selected, and its growth on GO sheets achieved through situ crystallization, leading formation MOF–GO composites varying content, MIL-101/GO(x%), (x = 1%, 2%, 5%). The oxygen functional groups 2D-GO layer e.g., carboxyl, hydroxyl, epoxy improve both acidity hydrophilicity composite, which directly contributes improved conductivity. All composites, fabricated work, exhibit higher than that parent due additional acidic introduced by GO. Among different MIL-101/GO(2%) exhibits highest achieving superprotonic value 0.105 S cm–1 at 80 °C 98% relative humidity (RH). These results highlight potential their application nanofillers exchange membranes membrane fuel cells (PEMFCs) other energy-related technologies.

Language: Английский

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Boosting proton conductivity: Integrating rigid porous aromatic frameworks into sulfonated poly(ether ether ketone) membranes

Inorganic Chemistry Communications, Journal Year: 2025, Volume and Issue: unknown, P. 114348 - 114348

Published: March 1, 2025

Language: Английский

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