Hydrogel‐Based Flexible Electronics

Advanced Materials, Journal Year: 2022, Volume and Issue: 35(14)

Published: Aug. 29, 2022

Abstract Flexible electronics is an emerging field of research involving multiple disciplines, which include but not limited to physics, chemistry, materials science, electronic engineering, and biology. However, the broad applications flexible are still restricted due several limitations, including high Young's modulus, poor biocompatibility, responsiveness. Innovative aiming for overcoming these drawbacks boost its practical application highly desirable. Hydrogel a class 3D crosslinked hydrated polymer networks, exceptional material properties render it as promising candidate next generation electronics. Here, latest methods synthesizing advanced functional hydrogels state‐of‐art hydrogel‐based in various fields reviewed. More importantly, correlation between hydrogel device performance discussed here, have better understanding development by using environmentally responsive hydrogels. Last, perspectives on current challenges future directions multifunctional provided.

Language: Английский

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Transparent, Self‐Adhesive, Conductive Organohydrogels with Fast Gelation from Lignin‐Based Self‐Catalytic System for Extreme Environment‐Resistant Triboelectric Nanogenerators

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 32(28)

Published: April 28, 2022

Abstract Conductive hydrogels have shown great promise in the field of sustainable power sources due to their unique features sufficient flexibility, durability, and functional diversification. However, time‐ energy‐consuming polymerization process poor adaptability extreme environments severely impede practical application such an emerging field. Herein, a facile universal self‐catalytic system (AL‐Cu 2+ ) based on alkali lignin (AL) macromolecule has been designed rapidly fabricate conductive transparent organohydrogels alkaline water–ethylene glycol (EG) binary solvent, which displays environment applicability (‒40 60 °C), eligible stretchability (≈800% elongation), robust self‐adhesion (≈31.4 kPa). Interestingly, introduced EG accelerates polymerization, endows freezing/drying resistance, improves for organohydrogels. The organohydrogel (water/EG = 2/3) that combines above merits inspires construction triboelectric nanogenerator (O‐TENG) mechanical energy harvesting converting regardless low‐ or high‐temperature environments. generated electricity by O‐TENG can be used directly stored drive commercial electronics installed human joints movement monitoring. This work sheds light designing environment‐resistant flexible TENGs multifunctional soft materials with fast gelation strategy, provoking more attention high‐value utilization advanced applications.

Language: Английский

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Conductive polymer based hydrogels and their application in wearable sensors: a review

Materials Horizons, Journal Year: 2023, Volume and Issue: 10(8), P. 2800 - 2823

Published: Jan. 1, 2023

Hydrogels have been attracting increasing attention for application in wearable electronics, due to their intrinsic biomimetic features, highly tunable chemical-physical properties (mechanical, electrical, etc.), and excellent biocompatibility. Among many proposed varieties of hydrogels, conductive polymer-based hydrogels (CPHs) emerged as a promising candidate future sensor designs, with capability realizing desired features using different tuning strategies ranging from molecular design (with low length scale 10-10 m) micro-structural configuration (up 10-2 m). However, considerable challenges remain be overcome, such the limited strain sensing range mechanical strength, signal loss/instability caused by swelling/deswelling, significant hysteresis signals, de-hydration induced malfunctions, surface/interfacial failure during manufacturing/processing. This review aims offer targeted scan recent advancements CPH based technology, establishment dedicated structure-property relationships lab advanced manufacturing routes potential scale-up production. The CPHs sensors is also explored, suggested new research avenues prospects included.

Language: Английский

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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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Humidity Sensing of Stretchable and Transparent Hydrogel Films for Wireless Respiration Monitoring

Nano-Micro Letters, Journal Year: 2022, Volume and Issue: 14(1)

Published: Sept. 12, 2022

Respiratory monitoring plays a pivotal role in health assessment and provides an important application prospect for flexible humidity sensors. However, traditional sensors suffer from trade-off between deformability, sensitivity, transparency, thus the development of high-performance, stretchable, low-cost is urgently needed as wearable electronics. Here, ultrasensitive, highly deformable, transparent are fabricated based on cost-effective polyacrylamide-based double network hydrogels. Concomitantly, general method preparing hydrogel films with controllable thickness proposed to boost sensitivity hydrogel-based due extensively increased specific surface area, which can be applied different polymer networks facilitate integrated In addition, sustainable tapioca rich hydrophilic polar groups introduced first time second cross-linked network, exhibiting excellent water adsorption capacity. Through synergistic optimization structure composition, obtained film exhibits ultrahigh 13,462.1%/%RH, unprecedented. Moreover, film-based sensor repeatability ability work normally under stretching even enhanced sensitivity. As proof concept, we integrate stretchable specially designed wireless circuit mask fabricate respiratory interruption detection system Bluetooth transmission, enabling real-time human status. This strategy construct miniaturized next-generation devices various physiological signals.

Language: Английский

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Metal‐Organic Framework Reinforced Highly Stretchable and Durable Conductive Hydrogel‐Based Triboelectric Nanogenerator for Biomotion Sensing and Wearable Human‐Machine Interfaces

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(48)

Published: July 17, 2023

Abstract Flexible triboelectric nanogenerators (TENGs) with multifunctional sensing capabilities offer an elegant solution to address the growing energy supply challenges for wearable smart electronics. Herein, a highly stretchable and durable electrode TENG is developed using ZIF‐8 as reinforcing nanofiller in hydrogel LiCl electrolyte. nanocrystals improve hydrogel's mechanical properties by forming hydrogen bonds copolymer chains, resulting 2.7 times greater stretchability than pure hydrogel. The encapsulated microstructured silicone layers that act materials prevent water loss from Optimized ZIF‐8‐based electrodes enhance output performance of through dynamic balance electric double (EDLs) during contact electrification. Thus, as‐fabricated delivers excellent power density 3.47 Wm – 2 , which 3.2 higher hydrogel‐based TENG. can scavenge biomechanical even at subzero temperatures small electronics serve self‐powered pressure sensors human‐machine interfaces (HMIs). nanocomposite also function biomotion sensor, detecting body movements high sensitivity. This study demonstrates significant potential utilizing reinforced TENGs harvesting sensor technology.

Language: Английский

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Anti-freezing, recoverable and transparent conductive hydrogels co-reinforced by ethylene glycol as flexible sensors for human motion monitoring

International Journal of Biological Macromolecules, Journal Year: 2023, Volume and Issue: 230, P. 123117 - 123117

Published: Jan. 2, 2023

Language: Английский

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Tough, Antifreezing, and Piezoelectric Organohydrogel as a Flexible Wearable Sensor for Human–Machine Interaction

ACS Nano, Journal Year: 2024, Volume and Issue: 18(4), P. 3720 - 3732

Published: Jan. 18, 2024

Piezoelectric hydrogel sensors are becoming increasingly popular for wearable sensing applications due to their high sensitivity, self-powered performance, and simple preparation process. However, conventional piezoelectric hydrogels lack antifreezing properties thus confronted with the liability of rupture in low temperatures owing use water as dispersion medium. Herein, a kind organohydrogel that integrates piezoelectricity, low-temperature tolerance, mechanical robustness, stable electrical performance is reported by using poly(vinylidene fluoride) (PVDF), acrylonitrile (AN), acrylamide (AAm),

Language: Английский

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Hydrophobic and Stable Graphene-Modified Organohydrogel Based Sensitive, Stretchable, and Self-Healable Strain Sensors for Human-Motion Detection in Various Scenarios

ACS Materials Letters, Journal Year: 2022, Volume and Issue: 4(9), P. 1616 - 1629

Published: July 27, 2022

Developing stretchable/wearable strain sensors in different application scenarios is a global demand for creating smart society and promoting healthcare, whereas existing hydrogel-based suffer from limited sensitivity, low conductance hydrophilicity, making them difficult to operate underwater. In this work, highly sensitive, stretchable, hydrophobic sensor fabricated by coating layer of reduced graphene oxide (rGO) sheets on the surface organohydrogel. Furthermore, facile solvent-replacement approach utilized enhance anti-freezing anti-drying abilities hydrogel simultaneously incorporating propanediol solvent. Consequently, obtained rGO-organohydrogel composite features high gauge factor 140, detection limit 0.1% strain, wide range (0–400% strain), fast response time 190 ms, excellent stability repeatability, hydrophobicity (contact angle 122°), it applicable scenarios, such as real-time continuous monitoring various human motions extremely cold (−60 °C), dry, underwater environments. The sensitivity an rGO-modified organohydrogel more than 30 times higher that its unmodified counterpart, which attributed cracking tunneling effects introduced conductive rGO upon stretching.

Language: Английский

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Human Nervous System Inspired Modified Graphene Nanoplatelets/Cellulose Nanofibers‐Based Wearable Sensors with Superior Thermal Management and Electromagnetic Interference Shielding

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(28)

Published: March 10, 2024

Abstract Wearable sensing technologies have witnessed rapid development in recent years due to their accessibility, functionality, and affordability. However, heat accumulation electromagnetic interference electronic components adversely affect the performance seriously damage human health. Herein, cellulose nanofibers (CNFs)‐based composites with high thermal conductivity (TC) excellent (EMI) shielding are prepared using CNFs as templates followed by coating tannic acid non‐covalent 3‐aminopropyltriethoxysilane covalent co‐modified graphene nanoplatelets (denoted mGNPs) through a simple electrostatic self‐assembly method. The subsequent hot‐pressing process yield order layer mGNPs CNFs‐based distributed along orientation close contact CNFs, fashion similar nervous system. resulting reveal TC of 136.2 W/(m·K) superior EMI effectiveness 105 dB. Thus, they used wearable sensors based on triboelectric effect monitor health real‐time, well express emotion Morse code. In sum, proposed strategy provides an avenue prolong service life flexible ensure safe use, promising for future wisdom healthcare smart robotics.

Language: Английский

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