A Breathable, Stretchable, and Self‐Calibrated Multimodal Electronic Skin Based on Hydrogel Microstructures for Wireless Wearables

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(32)

Published: April 12, 2024

Abstract Biomimetic electronic skins (e‐skins) are widely used in wearables, smart prosthesis and soft robotics. However, multimodal e‐skins, especially those based on hydrogels, face multiple challenges for practical applications, involving multi‐sensing signal mutual interference, low breathability stretchability. Here, a breathable stretchable e‐skin with multilayer film microstructure is developed to achieve self‐calibrated sensing of any two three stimuli: strain, temperature, humidity, minimal crosstalk. Hydrogel fibers different shapes designed strain temperature modules, the hydrogel as humidity module. The exhibits impressive performance, including detection limit (0.03%), linearity (R 2 = 0.990), high‐temperature sensitivity (1.77%/°C), wide range (33–98% RH). Interestingly, due directional anisotropy shaped fibers, realizes directions. By introducing porous elastomer encapsulation membranes, wearing comfort attained, while high stretchability (100% strain) maintained. Furthermore, personalized human‐machine interaction system created by integrating wireless circuit realize real‐time gesture recognition, physiological signals monitoring, prosthesis.

Language: Английский

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Ultra-Tough, highly stable and Self-Adhesive Goatskin-Based intelligent Multi-Functional organogel e-skin as Temperature, Humidity, Strain, and bioelectric four-mode sensors for health monitoring

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 485, P. 149816 - 149816

Published: Feb. 19, 2024

Language: Английский

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Wireless Technologies in Flexible and Wearable Sensing: From Materials Design, System Integration to Applications

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(27)

Published: April 23, 2024

Wireless and wearable sensors attract considerable interest in personalized healthcare by providing a unique approach for remote, noncontact, continuous monitoring of various health-related signals without interference with daily life. Recent advances wireless technologies have promoted practical applications due to their significantly improved characteristics, such as reduction size thickness, enhancement flexibility stretchability, conformability the human body. Currently, most researches focus on active materials structural designs sensors, just few exceptions reflecting data transmission. This review provides comprehensive overview state-of-the-art related studies empowering sensors. The emerging functional nanomaterials utilized designing modules are highlighted, which include metals, carbons, MXenes. Additionally, outlines system-level integration flexible spanning from novel design strategies enhanced efficient transmitting wirelessly. Furthermore, introduces representative remote noninvasive physiological through on-skin implantable sensing systems. Finally, challenges, perspectives, unprecedented opportunities discussed.

Language: Английский

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Skin‐Like Transparent, High Resilience, Low Hysteresis, Fatigue‐Resistant Cellulose‐Based Eutectogel for Self‐Powered E‐Skin and Human–Machine Interaction

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 34(13)

Published: Dec. 14, 2023

Abstract Artificial electronic skin (E‐skin), a class of promising materials mimicking the physical‐chemical and sensory performance human skin, has gained extensive interest in field health‐monitoring robotic skins. However, developing E‐skin simultaneously achieving high resilience, hysteresis‐free, absent external power is always formidable challenge. Herein, liquid‐free eutectic gel‐based self‐powered with fatigue resistance, conductivity prepared by introducing hydroxypropyl cellulose (HPC) into metal salt‐based deep solvents (MDES). The unique structural design cellulose‐anchored permanent entangled poly(acrylic acid) (PAA) chain, combination rapid broken/reconstruction dense dynamic sacrificial bonds, realizes fabrication high‐elastic negligible hysteresis. This further demonstrates practical application cellulose‐based eutectogel transmittance (92%), (36.6 mS m −1 ), resilience (98.1%), excellent environment stability robust triboelectric nanogenerator for energy harvesting health‐caring human‐machine interaction.

Language: Английский

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Bionic ordered structured hydrogels: structure types, design strategies, optimization mechanism of mechanical properties and applications

Materials Horizons, Journal Year: 2023, Volume and Issue: 10(10), P. 4033 - 4058

Published: Jan. 1, 2023

In this paper, the structure types, optimization mechanism of mechanical properties and common application scenarios bionic ordered hydrogels are reviewed.

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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Robust Fiber‐Shaped Flexible Temperature Sensors for Safety Monitoring with Ultrahigh Sensitivity

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(18)

Published: Jan. 31, 2024

Abstract Flexible temperature sensors capable of detecting and transmitting data from the human body, environment, electronic devices hold significant potential for applications in skins, human–machine interactions, disaster prevention systems. Nonetheless, fabricating flexible with exceptional sensing performance remains a formidable task, primarily due to intricate process constructing an intrinsically element high sensitivity. In this study, facile situ two‐step synthetic method is introduced fiber‐shaped NiO/carbon nanotube fiber (CNTF) composites. The resulting NiO/CNTF demonstrate outstanding deformability characteristics, encompassing broad working range (−15 60 °C) sensitivity (maximum TCR −20.2% °C −1 B value 3332 K). Importantly, mechanical thermal behaviors sensor various application conditions are thoroughly examined using finite analysis simulations. Moreover, can effectively capture diverse signals wearable applications. Notably, monitoring warning system developed prevent fire accidents abnormal runaway devices.

Language: Английский

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Collagen fiber-reinforced, tough and adaptive conductive organohydrogel e-skin for multimodal sensing applications

Journal of Materials Chemistry B, Journal Year: 2024, Volume and Issue: 12(28), P. 6940 - 6958

Published: Jan. 1, 2024

Conductive hydrogels (CHs) with high sensitivity and multifunctional property are considered as excellent materials for wearable devices flexible electronics. Surface synapses internal multilayered structures key factors highly sensitive pressure sensors. Nevertheless, current CHs lack environmental adaptability, perception, instrument portability, which seriously hinders their application Here, waste collagen fibers (buffing dust of leather), polyvinyl alcohol (PVA) gelatin (Gel) were used the basic framework hydrogel, loaded a conductive material (silver nanoparticles (BD-CQDs@AgNPs)) an anti-freezing moisturizer (glycerol (Gly)), resulting in organohydrogel (BPGC-Gly). As temperature humidity sensor, it demonstrated response range (-20-60 °C) was capable rapid (2.4 s) recovery (1.6 to human breathing. strain/pressure allowed real-time monitoring movement had low-pressure (

Language: Английский

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Robust, Efficient, and Recoverable Thermocells with Zwitterion‐Boosted Hydrogel Electrolytes for Energy‐Autonomous and Wearable Sensing

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(29)

Published: April 29, 2024

Abstract The rapid growth of flexible quasi‐solid‐state thermocells (TECs) provides a fresh way forward for wearable electronics. However, their insufficient mechanical strength and power output still hinder further applications. This work demonstrates one‐stone‐two‐birds strategy to synergistically enhance the thermoelectrochemical properties [Fe(CN) 6 ] 3−/4− ‐based TECs. By introducing Hofmeister effect multiple non‐covalent interactions via betaine zwitterions, conventional brittle gelatin hydrogel electrolytes is substantially improved from 50 440 kPa, with high stretchability approaching 250 %. Meanwhile, zwitterions strongly affect solvation structure 3− ions, thus enlarging entropy difference raising Seebeck coefficient 1.47 2.2 mV K −1 . resultant TECs exhibit normalized density 0.48 mW m −2 , showing notable improvement in overall performance compared counterparts without zwitterion regulation. intrinsic thermo‐reversible property also allows repeatedly self‐recover through sol‐gel transformations, ensuring reliable energy even recycling case extreme damages. An energy‐autonomous smart glove consisting eighteen individual designed, which can simultaneously monitor temperature different positions on any touched object, demonstrating potential

Language: Английский

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Ultra-Flexible, Anti-Freezing, and Adhesive Collagen Fiber-Derived Conductive Organohydrogel E-Skin for Strain, Humidity, Temperature, and Bioelectric Sensing Applications

Chemistry of Materials, Journal Year: 2024, Volume and Issue: 36(17), P. 8141 - 8158

Published: Aug. 15, 2024

The development of biomimetic electronic skin (e-skin) has significant value in many fields, including health monitoring, soft robotics, wearable devices, and human-machine interaction. As a potential candidate for e-skin, the application conductive hydrogel is limited by factors, such as complicated fabrication process, insufficient mechanical performance, poor environmental stability, difficulty degradation. Here, we adopted top-down strategy to construct multifunctional collagen fiber-derived organohydrogel which fiber scaffold goatskin was filled with polyacrylamide network. This displayed excellent fracture stress (2.87 MPa) strain (542%). It could maintain its multifunctionality even at −20 °C after long-term storage. Additionally, this demonstrated considerable adhesion antibacterial properties, allowing it conform closely human without causing bacterial infection. e-skin sensors, assembled organohydrogel, possessed multiple stimuli-responsive modes achieve strain, humidity, temperature, bioelectric responsiveness, precise monitoring body movements, facial expressions, voice communication, physiological signals. Notably, discarded be effectively degraded under natural conditions. In brief, study gives new opinions about intelligent demonstrates pathway high-value utilization animal skin.

Language: Английский

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