Mechanically Strong, Freeze‐Resistant, and Ionically Conductive Organohydrogels for Flexible Strain Sensors and Batteries

Advanced Science, Journal Year: 2023, Volume and Issue: 10(9)

Published: Jan. 19, 2023

Abstract Conductive hydrogels as promising material candidates for soft electronics have been rapidly developed in recent years. However, the low ionic conductivity, limited mechanical properties, and insufficient freeze‐resistance greatly limit their applications flexible wearable electronics. Herein, aramid nanofiber (ANF)‐reinforced poly(vinyl alcohol) (PVA) organohydrogels containing dimethyl sulfoxide (DMSO)/H 2 O mixed solvents with outstanding are fabricated through solution casting 3D printing methods. The show both high tensile strength toughness due to synergistic effect of ANFs DMSO system, which promotes PVA crystallization intermolecular hydrogen bonding interactions between molecules well PVA, confirmed by a suite characterization molecular dynamics simulations. also exhibit ultrahigh ranging from 1.1 34.3 S m −1 at −50 60 °C. Building on these excellent organohydrogel‐based strain sensors solid‐state zinc–air batteries (ZABs) fabricated, broad working temperature range. Particularly, ZABs not only specific capacity (262 mAh g ) ultra‐long cycling life (355 cycles, 118 h) even −30 °C, but can work properly under various deformation states, manifesting great potential robotics

Language: Английский

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Flexible electronics for cardiovascular healthcare monitoring

The Innovation, Journal Year: 2023, Volume and Issue: 4(5), P. 100485 - 100485

Published: July 25, 2023

•Flexible electronics can revolutionize cardiovascular healthcare monitoring.•Flexible aid in promptly identifying disease indicators, enabling better personalized treatment.•Further developments include wireless design, miniaturization, multifunction, artificial intelligence-assisted diagnosis, virtual medicine, customized healthcare, etc. Cardiovascular diseases (CVDs) are one of the most urgent threats to humans worldwide, which responsible for almost one-third global mortality. Over last decade, research on flexible monitoring and treatment CVDs has attracted tremendous attention. In contrast conventional medical instruments hospitals that usually bulky, hard move, monofunctional, time-consuming, capable continuous, noninvasive, real-time, portable monitoring. Notable progress been made this emerging field, thus a number significant achievements concomitant prospects deserve attention practical implementation. Here, we comprehensively review latest CVDs, focusing new functions provided by electronics. First, characteristics foundation their combination briefly reviewed. Then, four representative applications elaborated: blood pressure (BP) monitoring, electrocardiogram (ECG) echocardiogram direct epicardium Their operational principles, progress, merits demerits, future efforts discussed. Finally, remaining challenges opportunities outlined.

Language: Английский

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An overview of conductive composite hydrogels for flexible electronic devices

Advanced Composites and Hybrid Materials, Journal Year: 2024, Volume and Issue: 7(2)

Published: Feb. 17, 2024

Language: Английский

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A Laminated Gravity‐Driven Liquid Metal‐Doped Hydrogel of Unparalleled Toughness and Conductivity

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 34(31)

Published: Oct. 6, 2023

Abstract Conductive hydrogels have been promising candidates for wearable and flexible electronics due to their high flexibility biocompatibility. However, the previously reported with conductivity over 1000 S m −1 usually poor mechanical properties including low tensile stress (<5 MPa) toughness (<2 MJ −3 ). Here, a liquid metal‐doped polyvinyl alcohol (PVA‐LM) hydrogel is presented, which simultaneously combines ultra‐high (maximum of 217 895 ) excellent properties, (15.44 MPa), large strain (704%), (43.02 fatigue resistance. Such extremely afforded by self‐sintering behavior LM at bottom surface that enables formation conductive networks. The polymer crystalline regions polymer‐tannic acid multiple hydrogen bonds are responsible impressive hydrogels. Particularly, electric filler could be recycled in robust dissociation dynamic interactions. Most importantly, electrodes capacitive sensors developed utilizing PVA‐LM hydrogel. These devices enable accurate monitoring bioelectrical signals human motions, highlighting immense potential realm soft technology.

Language: Английский

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A Freeze‐Resistant, Highly Stretchable and Biocompatible Organohydrogel for Non‐Delayed Wearable Sensing at Ultralow‐Temperatures

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(16)

Published: Jan. 2, 2024

Abstract Wearable electronics based on conductive hydrogels (CHs) easily suffer from prolonged response times, reduced wearing comfort, shortened service lives, and impaired signal accuracy in cold environments, because conventional CHs tend to freeze at subzero temperatures lose their flexibility, adhesion, transparency, conductivity, which will limit applications extreme environments. Inspired by the way psychrotolerant creatures superabsorbent materials interfere with hydrogen bonding networks of water, a freeze‐resistant organohydrogel (COH) is facilely fabricated. The synergy effect between charged polar terminal groups binary solvent system water–ethylene glycol weakens water molecules endows COH remarkable freezing tolerance (−78 °C). Additionally, obtained ultra‐stretchable (≈6185%), tough (9.2 MJ m −3 ), highly transparent (≈99%), self‐adhesive (10.2–27.8 kPa), biocompatible. This versatile assembled into strain sensor well‐designed bracelet electrocardiogram sensor. Benefiting exceptional low‐temperature prepared COH, these devices exhibit fast delay‐free signals even −40 °C. Overall, this work proposes strategy develop multifunctional COHs for supporting human health

Language: Английский

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Enhanced mechanical strength and stretchable ionic conductive hydrogel with double-network structure for wearable strain sensing and energy harvesting

Composites Science and Technology, Journal Year: 2024, Volume and Issue: 255, P. 110732 - 110732

Published: July 2, 2024

Language: Английский

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Portable and Flexible Hydrogel Sensor for On-Site Atrazine Assay on Agricultural Products

Analytical Chemistry, Journal Year: 2024, Volume and Issue: 96(19), P. 7772 - 7779

Published: May 3, 2024

There is growing attention focused toward the problems of ecological sustainability and food safety raised from abuse herbicides, which underscores need for development a portable reliable sensor simple, rapid, user-friendly on-site analysis herbicide residues. Herein, novel multifunctional hydrogel composite explored to serve as flexible facile efficient atrazine (ATZ) The electrode fabricated by doping graphite-phase carbon nitride (g-C3N4) into aramid nanofiber reinforced poly(vinyl alcohol) via simple solution-casting procedure. Benefiting excellent electroactivity large specific surface area solid nanoscale component, prepared capable sensitive detection ATZ with limit down 0.002 ng/mL per test time less than 1 min. After combination smartphone-controlled electrochemical analyzer, exhibited satisfactory analytical performance assay. We further demonstrated applications in evaluation residues real water soil samples well point-of-need on various agricultural products. envision that this will open new avenue next-generation tools monitoring environment

Language: Английский

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Mechanically Robust and Thermal Insulating Nanofiber Elastomer for Hydrophobic, Corrosion‐Resistant, and Flexible Multifunctional Electromagnetic Wave Absorbers

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 7, 2024

Abstract Multifunctionalization of electromagnetic wave absorbing materials (EMWAMs) presents a promising avenue for their application in complex scenarios. However, the effective integration multiple supplementary functions into EMWAMs continues to pose significant challenge. Herein, novel nanofiber elastomer (NFE) incorporating multicomponent inorganic FeS 2 /S,N co‐doped carbon nanofibers (NFs) and organic component (Ecoflex) are designed synthesized. The sulfur doping ratios species can be effectively modulated via controlling amount sulfurization temperature. optimized NFs/Ecoflex NFE not only exerted an excellent impedance matching characteristic, but also displays boosted conductive loss polarization capacities. Amongst, achieved ultra‐wide absorption bandwidth (EAB) 7.40 GHz minimum reflection (RL min ) −21.82 dB at thin thickness (≈2.00 mm). Furthermore, simultaneously greatly improved mechanical property, thermal insulation, hydrophobicity, corrosion resistance. Through designing metastructures, with periodically closed‐ring resonant structure realized EAB 32.64 (ranging from 7.36 40.00 GHz). Overall, this research contributes valuable insights design next‐generation satisfactory multifunctionalities, demonstrating potential smart devices challenging environments.

Language: Английский

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UV-induced ferric phytate access to fast gelation of conductive and anti-freezing hydrogels for cryogenic strain sensing

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 482, P. 148847 - 148847

Published: Jan. 17, 2024

Language: Английский

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Mechanically Robust and Thermal Insulating Silica/Aramid Nanofiber Composite Aerogel Fibers with Dual Networks for Fire‐Resistant and Flexible Triboelectric Nanogenerators

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 22, 2024

Abstract Aerogel fibers, known for their lightweight and exceptional thermal insulation properties, provide an ideal material solution fabricating triboelectric nanogenerators (TENGs) self‐powered wearable electronics in extreme environments, such as firefighting gear. However, current aerogel fibers face limitations due to poor mechanical properties lack of performance stability under harsh conditions. Herein, a facile strategy preparing silica/aramid nanofiber (ANF) composite with interpenetrated dual networks silica‐dominant component (≈64 wt.%) is demonstrated; the unique structure composition endow high tensile strength (3.4 MPa), low conductivity (0.033 W (m·K) −1 ), large specific surface area (587 m 2 g outstanding fire resistance at 95% porosity, combining best both ANF silica aerogel. Moreover, exhibit excellent flexibility extremely temperatures (−196 °C) maintain structural integrity even when exposed flame up 5 min. Leveraging these fiber‐based TENGs show electrical output before after combustion (>94% retention). The fabrication offers promising opportunities modulating functionalities on demand, holding great potential future applications smart protective fabrics environments.

Language: Английский

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