Multiscale Covalent Organic Framework (COF) Films for Task-Specific Sensing in Multicomponent Gases

ACS Materials Letters, Journal Year: 2024, Volume and Issue: unknown, P. 5454 - 5478

Published: Nov. 18, 2024

Gas sensing is vital for ecological protection in agriculture, early disease diagnosis biomedicine, and safety industrial production. Covalent organic frameworks (COFs), a new class of porous polymer materials, can be customized through specific ligand selection to tailor pore sizes active sites, enabling them selectively enrich interact with targeted gas molecules, making promising candidates sensing. To advance their use this field, it essential investigate the mechanisms complex interactions between COFs target molecules as well improve COF film fabrication methods. This review outlines design strategies films across multiscale: molecular interaction mechanisms, macroscopic interfacial synthesis methods, microscale/nanoscale approaches such double-layer filtration micro/nanostructured improved transfer. Finally, several key research directions are proposed suitability COF-based materials environments.

Language: Английский

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Rational MOF Membrane Design for Gas Detection in Complex Environments

Small, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 23, 2024

Abstract Metal‐organic frameworks (MOFs) hold significant promise in the realm of gas sensing. However, current understanding their sensing mechanisms remains limited. Furthermore, large‐scale fabrication MOFs is hampered by inadequate mechanical properties. These two challenges contribute to sluggish development MOF‐based gas‐sensing materials. In this review, selection metal ions and organic ligands for designing first presented, deepening interactions between different ions/organic target gases. Subsequently, typical interfacial synthesis strategies (gas‐solid, gas‐liquid, solid‐liquid interfaces) are provided, highlighting potential constructing MOF membranes on superhydrophobic and/or superhydrophilic substrates. Then, a multi‐scale structure design proposed, including multi‐dimensional membrane heterogeneous design, improve performance through enhanced mass transfer specific sieving. This strategy anticipated augment task‐specific capabilities materials complex environments. Finally, several key future research directions outlined with aim not only further investigate underlying principles but also achieve efficient detection gases amidst interfering elevated moisture levels.

Language: Английский

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Hammerhead Shark‐Inspired Microvillus‐Structured Ionic Elastomers for Wet Gas Sensing Based on Solvated Ion Transport

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 13, 2025

Abstract Water molecules are ubiquitous disruptors of conventional gas sensing materials, often leading to diminished performance in materials that reliant on electronic signal transmission. This creates the pressing need for efficient with anti‐humidity interference properties. Here, a hammerhead shark‐inspired microvillus‐structured ionic elastomer based transmission nanoconfined space is constructed by incorporating liquids into polymer matrix. The elastomers optimized microvillus structure demonstrated 1.68‐fold higher response than flat ones, short time (9 s) toward 30 ppm triethylamine (TEA), excellent selectivity and low limit detection (LOD) (104.56 ppb). Such serves as proof‐of‐concept effectively combining solvated ion transport design develop advanced systems. With such an evident (23.52%), similar (12 s), LOD (498.05 ppb), long‐term stability (at least days) achieved at relative humidity 70%. Mechanistic investigations revealed effective ions facilitated after sequential water TEA surroundings while significantly enhanced transport. Furthermore, utility system shrimp decay monitoring under wet conditions.

Language: Английский

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Enhanced Oxygen Vacancy Formation in Pt-WO₃ via W–OH Bond Cleavage Using Water-Based One-Step Electrospinning for High-Performance Gas Sensors

Langmuir, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 27, 2025

Oxygen vacancies play a crucial role in charge transport and surface states semiconductor metal oxides, significantly influencing various research fields, such as photocatalysis gas sensor. Developing effective strategies to generate oxygen thereby enhance device performance is highly desirable. In this study, we proposed water-based one-step electrospinning method introduce hydroxyl groups, leading the synthesis of Pt-decorated WO3 nanofibers (Pt-WO3(H2O)) with increased vacancies. Density functional theory calculations revealed that dissociation energy W-OH lower than W-O bonds, promoting formation via bond cleavage. These reduced adsorption acetone on surface, enhancing interactions. Consequently, Pt-WO3(H2O) sensor exhibited an ultrahigh response 82 1.8 ppm at 300 °C, which was about 1 order magnitude higher one fabricated by conventional electrospinning. findings indicate technique for generating oxide nanofibers. Our high-performance sensor, capable detecting low concentrations, holds great potential applications noninvasive health screening.

Language: Английский

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Nanomaterials‐Enabled Sensors for Detecting and Monitoring Chemical Warfare Agents

Small, Journal Year: 2024, Volume and Issue: 21(9)

Published: Dec. 26, 2024

Despite their restrictions under international treaties, many chemical warfare agents (CWAs) and toxic analogues are still used in various industrial sectors such as agriculture manufacturing. Thus, the need for sensitive selective CWA detection remains critical. Commercially available methods, while accurate, often bulky, expensive, require specialized personnel. Sensors incorporating nanomaterials present a promising alternative, offering rapid, portable, cost-effective due to unique properties, high surface area tunable reactivity. This review covers four main categories: nerve agents, blister blood choking highlighting recent progress nanosensor development each category. It discusses sensing mechanisms employed, including fluorescence, colorimetry, chemiresistivity, electrochemistry, Raman spectroscopy. these advancements, challenges remain, particularly regarding scalability, stability, selectivity of nanomaterials-based sensors complex environments. The concludes by emphasizing address explore novel nanomaterials, scalable nanomanufacturing techniques, integration artificial intelligence fully unlock potential homeland security personal safety.

Language: Английский

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