Stretchable electronics have been recognized as intriguing next-generation electronics that possess huge market value,and stretchable electronic conductors(SECs)are essential for stretchable electronics,which not only...Stretchable electronics have been recognized as intriguing next-generation electronics that possess huge market value,and stretchable electronic conductors(SECs)are essential for stretchable electronics,which not only can serve as critical functional components but also are the indispensable electronic connections bridging various electronic components within stretchable electronic systems.Herein,we offer a comprehensive review of recent progress in SECs including the material categories,structure designs,fabrication techniques,and applications.The characteristics,performance enhancement strategies,and application requirements are emphasized.Based on the recent advances,the existing challenges and future prospects are outlined and discussed.展开更多
To evaluate their performance,we constructed organic solar cells using PTB7/Y6 and PTB7-b-PNDI active layers,which were deposited on PET substrates coated with PEDOT:PSS.The ternary solar cells demonstrated an excelle...To evaluate their performance,we constructed organic solar cells using PTB7/Y6 and PTB7-b-PNDI active layers,which were deposited on PET substrates coated with PEDOT:PSS.The ternary solar cells demonstrated an excellent power conversion efficiency after being stretched by 38%.The stretchable organic solar cells were spin-coated on the flexible substrate.The electrodes were formed via liquid metal dropcoating.Solar cell devices based on PET/PH1000/PEDOT:PSS and PTB7:Y6:5% BCP active layer materials show better stretchability than the normal solar cells.The PTB7:Y6:5% BCP-based stretchable organic solar cell achieves a high PCE of 12.3%,and a PCE of 7.8% after stretching.Incorporating block copolymer additives improves the mechanical properties of organic solar cells,thereby enabling superior stretchability.展开更多
The scalable fabrication of stretchable conjugated polymer films via solution printing is essential for their practical application in largearea wearable electronics.However,the printed conjugated polymer films typica...The scalable fabrication of stretchable conjugated polymer films via solution printing is essential for their practical application in largearea wearable electronics.However,the printed conjugated polymer films typically exhibit high crystallinity,limiting their mechanical deformability.Herein,we propose a plasticizer-assisted printing strategy to simultaneously enhance the stretchability and electrical performance of films based on the conjugated polymer poly(3-(5-(5-methylselenophen-2-yl)thiophen-2-yl)-6-(5-methylthiophen-2-yl)-2,5-bis(4-octyltetradecyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione)(P(TDPP-Se)).The incorporation of a plasticizer trioctyl trimellitate(TOTM)promotes P(TDPP-Se)aggregation in initial solution,facilitates chain alignment under flow field,and shorten solidification process,thereby restricting randomly polymer crystallization.Consequently,a low-crystallinity film with favorable edge-on orientation,strong chain alignment and improved chain dynamics is realized,which effectively alleviates crystallites fragmentation and crack propagation under large strain.The TOTM-plasticized film exhibits approximately 2-fold improvements in fracture strain and charge mobility,along with superior mobility retention under 100%strain in comparison to the neat film.This study provides a feasible approach for microstructure control in printed stretchable conjugated polymer film.展开更多
Thermosetting polymers exhibit outstanding mechanical properties,thermal stability,and chemical resistance due to their permanently cross-linked network structures.However,the irreversible nature of covalent cross-lin...Thermosetting polymers exhibit outstanding mechanical properties,thermal stability,and chemical resistance due to their permanently cross-linked network structures.However,the irreversible nature of covalent cross-linking renders these materials non-reprocessable and non-recyclable,posing significant environmental challenges.Although healable polymers based on dynamic covalent bonds and supramolecular interactions have emerged as promising alternatives,a broadly applicable strategy utilizing metal-ligand coordination in thermoset systems remains underexplored.In this work,we present a robust and healable thermoset system fabricated via ring-opening metathesis polymerization(ROMP)of commercially available chelating norbornene comonomers.Cross-linking is accomplished through O-donor coordination to Lewis acidic metal centers,yielding polydicyclopentadiene(PDCPD)-based networks that demonstrate high mechanical strength(up to 60.8 MPa)and effective self-healing performance.This methodology offers a simple and scalable approach to developing high-performance,sustainable thermosetting materials.展开更多
Permeable electronics promise improved physiological comfort,but remain constrained by limited functional integration and poor mechanical robustness.Here,we report a three-dimensional(3D)permeable electronic system th...Permeable electronics promise improved physiological comfort,but remain constrained by limited functional integration and poor mechanical robustness.Here,we report a three-dimensional(3D)permeable electronic system that overcomes these challenges by combining electrospun SEBS nanofiber mats,high-resolution liquid metal conductors patterned via thermal imprinting(50μm),and a strain isolators(SIL)that protects vertical interconnects(VIAs)from stress concentration.This architecture achieves ultrahigh air permeability(>5.09 m L cm^(-2)min^(-1)),exceptional stretchability(750%fracture strain),and reliable conductivity maintained through more than 32,500 strain cycles.Leveraging these advances,we have integrated multilayer circuits,strain sensors,and a three-axis accelerometer to achieve a fully integrated,stretchable,permeable wireless real-time gesture recognition glove.The system enables accurate sign language interpretation(98%)and seamless robotic hand control,demonstrating its potential for assistive technologies.By uniting comfort,durability,and high-density integration,this work establishes a versatile platform for nextgeneration wearable electronics and interactive human-robot interfaces.展开更多
The increasing demand for flexible displays and wearable electronics has driven extensive efforts to develop stretchable organic lightemitting diodes(OLEDs).A critical challenge in this field is the creation of emissi...The increasing demand for flexible displays and wearable electronics has driven extensive efforts to develop stretchable organic lightemitting diodes(OLEDs).A critical challenge in this field is the creation of emissive layers that combine high efficiency with mechanical robustness.Thermally activated delayed fluorescence(TADF)materials have attracted significant attention as third-generation emitters capable of achieving 100%internal quantum efficiency;however,their application in stretchable OLEDs has been limited.In this study,we propose an elastomer doping strategy.Polyurethane(PU)is incorporated into TADF polymers to improve their mechanical flexibility while maintaining a high luminescent efficiency.The resulting composite films exhibited excellent TADF characteristics and remarkable stretchability(75%).OLEDs fabricated from these materials achieved a maximum external quantum efficiency(EQE)of 14.26%and a peak luminance of 73570 cd·m^(-2),with the PUdoped devices showing a significantly suppressed efficiency roll-off.Additionally,a fully stretchable OLED architecture was designed and operated under tensile strain to maintain stable electroluminescent performance.These results demonstrate that elastomer doping is an effective strategy for balancing the mechanical compliance with optoelectronic performance,offering a promising pathway for the development of high-performance stretchable OLEDs for flexible electronics.展开更多
With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin...With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.展开更多
Intrinsic stretchability is a promising attribute of polymer organic solar cells(OSCs).However,rigid molecular blocks typically exhibit poor tensile properties,rendering polymers vulnerable to mechanical stress.In thi...Intrinsic stretchability is a promising attribute of polymer organic solar cells(OSCs).However,rigid molecular blocks typically exhibit poor tensile properties,rendering polymers vulnerable to mechanical stress.In this study,we introduce a different approach utilizing all-small-molecule donors and acceptors to fabricate stretchable OSCs.An elastomer,styrene-b-ethylene-butylene-styrene(SEBS),was embedded to modulate film crystallization and stretchability.SEBS effectively confines the growth process of donors and acceptors,leading to enhancement of the crystallization quality,thus contributing to enhanced device efficiencies.Meanwhile,SEBS can absorb and release mechanical stress during stretching,thereby preventing mechanical degradation of donors and acceptors.The mechanical properties of the OSCs were significantly improved by the incorporation of SEBS.Notably,the crack-onset strain increased from 1.03% to 5.99% with SEBS embedding.These findings present a straightforward strategy for achieving stretchable OSCs using all small molecules,offering a different perspective for realizing stretchable devices.展开更多
Soft polymer optical fiber(SPOF)has shown great potential in optical-based wearable and implantable biosensors due to its excellent mechanical properties and optical guiding characteristics.However,the multimodality c...Soft polymer optical fiber(SPOF)has shown great potential in optical-based wearable and implantable biosensors due to its excellent mechanical properties and optical guiding characteristics.However,the multimodality characteristics of SPOF limit their integration with traditional fiber optic sensors.This article introduces for the first time a flexible fiber optic vibration sensor based on laser interference technology,which can be applied to vibration measurement under high stretch conditions.This sensor utilizes elastic optical fibers made of polydimethylsiloxane(PDMS)as sensing elements,combined with phase generating carrier technology,to achieve vibration measurement at 50−260 Hz within the stretch range of 0−42%.展开更多
Bionic hydrogels offer significant advantages over conventional counterparts,boasting superior properties like enhanced adhesion,stretchability,conductivity,biocompatibility and versatile functionalities.Their physico...Bionic hydrogels offer significant advantages over conventional counterparts,boasting superior properties like enhanced adhesion,stretchability,conductivity,biocompatibility and versatile functionalities.Their physicochemical resemblance to biological tissues makes bionic hydrogels ideal interfaces for bioelectronic devices.In contrast,conventional hydrogels often exhibit inadequate performance,such as easy detachment,lack of good skin compliance,and inadequate conductivity,failing to meet the rigorous demands of bioelectronic applications.Bionic hydrogels,inspired by biological designs,exhibit exceptional physicochemical characteristics that fulfill diverse criteria for bioelectronic applications,driving the advancement of bioelectronic devices.This review first introduces a variety of materials used in the fabrication of bionic hydrogels,including natural polymers,synthetic polymers,and other materials.Then different mechanisms of hydrogel bionics,are categorized into material bionics,structural bionics,and functional bionics based on their bionic approaches.Subsequently,various applications of bionic hydrogels in the field of bioelectronics were introduced,including physiological signal monitoring,tissue engineering,and human-machine interactions.Lastly,the current development and future prospects of bionic hydrogels in bioelectronic devices are summarized.Hopefully,this comprehensive review could inspire advancements in bionic hydrogels for applications in bioelectronic devices.展开更多
The Design and manufacturing of a noble piezoresistive pressure sensor(PS) for subtle pressures(<1 kPa) were presented. Meanwhile, in the studies conducted in the field of pressure sensors, the measurement of subtl...The Design and manufacturing of a noble piezoresistive pressure sensor(PS) for subtle pressures(<1 kPa) were presented. Meanwhile, in the studies conducted in the field of pressure sensors, the measurement of subtle pressures has received less attention. The limitations in the inherent gauge factor in silicon, have led to the development of polymer and composite resistive sensitive elements. However,in the development of resistance sensing elements, the structure of composite elements with reinforcement core has not been used. The proposed PS had a composite sandwich structure consisting of a nanocomposite graphene layer covered by layers of PDMS at the bottom and on the top coupled with a polyimide(PI) core. Various tests were performed to analyze the PS. The primary design target was improved sensitivity, with a finite-element method(FEM) utilized to simulate the stress profile over piezoresistive elements and membrane deflection at various pressures. The PS manufacturing process is based on Laser-engraved graphene(LEG) technology and PDMS casting. Experimental data indicated that the manufactured PS exhibits a sensitivity of 67.28 mV/kPa for a pressure range of 30-300 Pa in ambient temperature.展开更多
As a natural biopolymer material,silk fibroin with unique mechanical properties can be used in the preparation of biocomposite hydrogels for strain sensors.But,the electromechanical properties of bio-composite hydroge...As a natural biopolymer material,silk fibroin with unique mechanical properties can be used in the preparation of biocomposite hydrogels for strain sensors.But,the electromechanical properties of bio-composite hydrogel strain sensors are still insufficient,such as the deterioration of electrical signals and low sensitivity,which need to develop a hydrogel with a stable transmission network for electric con-duction.Herein,a silk fibroin biocomposite hydrogel is prepared by incorporating tannic acid and MXene nanosheets into a polyacrylamide and silk fibroin double network.The electromechanical properties of hydrogels are improved by optimizing the proportion of material components.As a result,the double network structure and supramolecular interaction enhance the stretchability of hydrogels(692% fracture strain).The hydrogel also exhibits good biocompatibility and conductivity(0.85 S/m),which shows the application prospect in wearable sensors.The wireless strain sensor assembled by this biocomposite hy-drogel presents good portability and sensing performance,such as high sensitivity(gauge factor=6.04),wide working range(500% strain),and outstanding stability(1000 cycles at 100%strain).The results in-dicate that the hydrogel strain sensor can be used to monitor human body movement.The biocomposite hydrogel is expected to be applied in the field of wearable strain sensors,and this study can provide a new way for the design of flexible electronic materials.展开更多
Flexible and stretchable energy storage devices are highly desirable for wearable electronics,particularly in the emerging fields of smart clothes,medical instruments,and stretchable skin.Lithium metal batteries(LMBs)...Flexible and stretchable energy storage devices are highly desirable for wearable electronics,particularly in the emerging fields of smart clothes,medical instruments,and stretchable skin.Lithium metal batteries(LMBs) with high power density and long cycle life are one of the ideal power sources for flexible and stretchable energy storage devices.However,the current LMBs are usually too rigid and bulky to meet the requirements of these devices.The electrolyte is the critical component that determines the energy density and security of flexible and stretchable LMBs.Among various electrolytes,gel polymer electrolytes(GPEs) perform excellent flexibility,safety,and high ionic conductivity compared with traditional liquid electrolytes and solid electrolytes,fulfilling the next generation deformable LMBs.This essay mainly reviews and highlights the recent progress in GPEs for flexible/stretchable LMBs and provides some useful insights for people interested in this field.Additionally,the multifunctional GPEs with self-healing,flame retardant,and temperature tolerance abilities are summarized.Finally,the perspectives and opportunities for flexible and stretchable GPEs are discussed.展开更多
Intrinsically stretchable semiconducting polymers play a vital role in the development of wearable electronics,featuring low-cost,large-area and high-density fabrication.Only single-stage dynamic chemical bond has bee...Intrinsically stretchable semiconducting polymers play a vital role in the development of wearable electronics,featuring low-cost,large-area and high-density fabrication.Only single-stage dynamic chemical bond has been widely incorporated into polymer backbones to afford stretchability while multiple dynamic bonds have not been investigated,making a formidable challenge to achieve high stretchability without compromising charge transport properties.Herein,we synthesize a series of stretchable polymer semiconductors incorporating urethane and bipyridine units,which can provide dynamic interconnected polymer network by combination of hydrogen bonds with metal coordination,simultaneously obtaining excellent stretchability and carrier mobilities.Compared with single-stage hydrogen bonds,multiple dynamic chemical bonds constructed by 10% hydrogen bonds and 0.25 equiv.metal coordination endowed the polymer semiconductors with an 58% enhancement in carrier mobility and a two-fold increase in crack-onset strain.Notably,the polymer exhibited stable carrier mobilities parallel to the stretching direction,with 91% of initial values even under 150% strain,which is the unprecedented value for intrinsically stretchable semiconducting polymers without blending of elastomers.Therefore,the introduction of multiple dynamic bonds provides an effective and promising approach for intrinsically stretchable and high-performance polymer semiconductor.展开更多
Triboelectric nanogenerators(TENGs)are emerging as new technologies to harvest electrical power from mechanical energy.With the distinctive working mechanism of triboelectric nanogenerators,they attract particular int...Triboelectric nanogenerators(TENGs)are emerging as new technologies to harvest electrical power from mechanical energy.With the distinctive working mechanism of triboelectric nanogenerators,they attract particular interest in healthcare monitoring,wearable electronics,and deformable energy harvesting,which raises the requirement for highly conformable devices with substantial energy outputs.Here,a simple,low-cost strategy for fabricating stretchable triboelectric nanogenerators with ultra-high electrical output is developed.The TENG is prepared using PTFE micron particles(PPTENG),contributing a different electrostatic induction process compared to TENG based on dielectric films,which was associated with the dynamics of particle motions in PP-TENG.The generator achieved an impressive voltage output of 1000 V with a current of 25 lA over a contact area of 40320 mm^(2).Additionally,the TENG exhibits excellent durability with a stretching strain of 500%,and the electrical output performance does not show any significant degradation even after 3000 cycles at a strain of 400%.The unique design of the device provides high conformability and can be used as a self-powered sensor for human motion detection.展开更多
Stretchable conductive fibers are essential for the advancement of wearable electronic textiles.However,a significant challenge arises as their conductivity sharply decreases when stretched due to disruptions in elect...Stretchable conductive fibers are essential for the advancement of wearable electronic textiles.However,a significant challenge arises as their conductivity sharply decreases when stretched due to disruptions in electronic transport.Coating fibers with soft liquid metal(LM)has emerged as a promising solution.Despite this,there remains an urgent need to develop methods that enhance LM adhesion to substrates while facilitating efficient electron transport pathways.This study demonstrates a novel Ag-LM conductive network strategy for fabricating a thermoplastic polyurethane/polydopamine/silver-LM(TPU/PDA/Ag-LM)fiber membrane.This membrane exhibits outstanding stretchable electromagnetic interference(EMI)shielding performance and is produced through straightforward electrospinning,electroless depositing,and LM coating and activation.The TPU/PDA/Ag fiber membrane is initially prepared via polydopamineassisted deposition of silver nanoparticles(AgNPs)on electrospun TPU fibers.The presence of AgNPs on the surface of TPU/PDA fibers enhances LM adhesion to the substrate and bridges adjacent LM to establish efficient conductive paths.This interaction benefits from the reactive alloying between AgNPs and LM,where the LM infiltrates the gaps among AgNPs,forming a distinctive LM-Ag alloy layer that uniformly coats the surface of TPU fibers.As anticipated,the unique three-dimensional(3D)interconnected LM-Ag conductive network remains intact during stretching,ensuring strain-invariant conductivity.The fabricated TPU/PDA/Ag-LM fiber membrane demonstrates exceptional EMI shielding effectiveness(SE)of 77.4 dB within the frequency range of 8.2-12.8 GHz and maintains an excellent EMI SE of 37.2 dB under extensive tensile deformation of 300%.Furthermore,the TPU/PDA/Ag-LM fiber membrane shows remarkable mechanical properties and stable Joule heating performance even under significant stretching.展开更多
This paper examines the transport analysis,including both heat transfer and mass transfer,in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface.The influence of magnetic fi...This paper examines the transport analysis,including both heat transfer and mass transfer,in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface.The influence of magnetic fields is also inspected in terms of their physical characteristics.To depict the phenomena of transport,modified versions of both Fick's and Fourier's laws are used.Additionally,the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated.Utilizing a curvilinear coordinate system,the flow problem is formulated as partial differential equations(PDEs)for momentum,concentration,microorganism field,and energy.An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).The effects of significant flow parameters on the pressure and microorganism fields,velocity,oscillation velocity,concentration,and temperature distributions are shown via graphs.Furthermore,the variations in skin friction,mass transfer rate,heat transfer rate,and local motile number due to different involved parameters are presented in tables and are analyzed in detail.Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables increase.It is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase,and it increases with the Schmidt number and the heterogeneous reaction strength parameter.Tabular outcomes show a favorable response of the motile number to advanced values of the Peclet number,the Schmidt number,the microorganism difference parameter,and the bio-convective Lewis number.展开更多
The flourishing development in flexible electronics has provoked intensive research in flexible strain sensors to realize accurate perception acquisition under different external stimuli.However,building hydrogel-base...The flourishing development in flexible electronics has provoked intensive research in flexible strain sensors to realize accurate perception acquisition under different external stimuli.However,building hydrogel-based strain sensors with high stretchability and sensitivity remains a great challenge.Herein,MXene nanosheets were composited into polyacrylamide-sodium alginate matrix to construct mechanical robust and sensitive double networked hydrogel strain sensor.The hydrophilic MXene nanosheets formed strong interactions with the polymer matrix and endowed the hydrogel with excellent tensile properties(3150%),compliant mechanical strength(2.03 kPa^(-1)in Young’s Module)and long-lasting stability and fatigue resistance(1000 dynamic cycles under 1,600%strain).Due to the highly oriented MXene-based three dimensional conductive networks,the hydrogel sensor achieved extremely high tensile sensitivity(18.15 in gauge factor)and compression sensitivity(0.38 kPa^(-1)below 3 kPa).MXene hydrogel-based strain sensors also displayed negligible hysteresis in electromechanical performance,typical frequent-independent feature and rapid response time to external stimuli.Moreover,the sensor exhibited accurate response to different scales of human movements,providing potential application in speech recognition,expression recognition and handwriting verification.展开更多
Continuous deforming always leads to the performance degradation of a flexible triboelectric nanogenerator due to the Young’s modulus mismatch of different functional layers.In this work,we fabricated a fiber-shaped ...Continuous deforming always leads to the performance degradation of a flexible triboelectric nanogenerator due to the Young’s modulus mismatch of different functional layers.In this work,we fabricated a fiber-shaped stretchable and tailorable triboelectric nanogenerator(FST-TENG)based on the geometric construction of a steel wire as electrode and ingenious selection of silicone rubber as triboelectric layer.Owing to the great robustness and continuous conductivity,the FST-TENGs demonstrate high stability,stretchability,and even tailorability.For a single device with ~6 cm in length and ~3 mm in diameter,the open-circuit voltage of ~59.7 V,transferred charge of ~23.7 nC,short-circuit current of ~2.67 μA and average power of ~2.13 μW can be obtained at 2.5 Hz.By knitting several FST-TENGs to be a fabric or a bracelet,it enables to harvest human motion energy and then to drive a wearable electronic device.Finally,it can also be woven on dorsum of glove to monitor the movements of gesture,which can recognize every single finger,different bending angle,and numbers of bent finger by analyzing voltage signals.展开更多
With the advent of the 5G era and the rise of the Internet of Things,various sensors have received unprecedented attention,especially wearable and stretchable sensors in the healthcare field.Here,a stretchable,self-he...With the advent of the 5G era and the rise of the Internet of Things,various sensors have received unprecedented attention,especially wearable and stretchable sensors in the healthcare field.Here,a stretchable,self-healable,self-adhesive,and room-temperature oxygen sensor with excellent repeatability,a full concentration detection range(0-100%),low theoretical limit of detection(5.7 ppm),high sensitivity(0.2%/ppm),good linearity,excellent temperature,and humidity tolerances is fabricated by using polyacrylamide-chitosan(PAM-CS)double network(DN)organohydrogel as a novel transducing material.The PAM-CS DN organohydrogel is transformed from the PAM-CS composite hydrogel using a facile soaking and solvent replacement strategy.Compared with the pristine hydrogel,the DN organohydrogel displays greatly enhanced mechanical strength,moisture retention,freezing resistance,and sensitivity to oxygen.Notably,applying the tensile strain improves both the sensitivity and response speed of the organohydrogel-based oxygen sensor.Furthermore,the response to the same concentration of oxygen before and after self-healing is basically the same.Importantly,we propose an electrochemical reaction mechanism to explain the positive current shift of the oxygen sensor and corroborate this sensing mechanism through rationally designed experiments.The organohydrogel oxygen sensor is used to monitor human respiration in real-time,verifying the feasibility of its practical application.This work provides ideas for fabricating more stretchable,self-healable,self-adhesive,and high-performance gas sensors using ion-conducting organohydrogels.展开更多
基金supported by the National Natural Science Foundation of China(52172170)Guangdong Natural Science Foundation for Distinguished Young Scholars(2023B1515020114)+2 种基金Fundamental Research Funds for the Central Universities(24lgqb003)Guangdong University Innovation and Enhancement Program(2024KTSCX003)Science and Technology Projects of Guangzhou(2025A04J4230).
文摘Stretchable electronics have been recognized as intriguing next-generation electronics that possess huge market value,and stretchable electronic conductors(SECs)are essential for stretchable electronics,which not only can serve as critical functional components but also are the indispensable electronic connections bridging various electronic components within stretchable electronic systems.Herein,we offer a comprehensive review of recent progress in SECs including the material categories,structure designs,fabrication techniques,and applications.The characteristics,performance enhancement strategies,and application requirements are emphasized.Based on the recent advances,the existing challenges and future prospects are outlined and discussed.
基金Funded by the Natural Science Foundation of Fujian Province (No. 2019J01716)the Fujian Provincial Department of Science and Technology (No.2019L3008)。
文摘To evaluate their performance,we constructed organic solar cells using PTB7/Y6 and PTB7-b-PNDI active layers,which were deposited on PET substrates coated with PEDOT:PSS.The ternary solar cells demonstrated an excellent power conversion efficiency after being stretched by 38%.The stretchable organic solar cells were spin-coated on the flexible substrate.The electrodes were formed via liquid metal dropcoating.Solar cell devices based on PET/PH1000/PEDOT:PSS and PTB7:Y6:5% BCP active layer materials show better stretchability than the normal solar cells.The PTB7:Y6:5% BCP-based stretchable organic solar cell achieves a high PCE of 12.3%,and a PCE of 7.8% after stretching.Incorporating block copolymer additives improves the mechanical properties of organic solar cells,thereby enabling superior stretchability.
基金supported by the National Natural Science Foundation of China(No.52433009)the Fundamental Research Funds for the Central Universities(No.GK202501005)the State Key Laboratory of Polymer Science and Technology(No.PST-KF2025-07)。
文摘The scalable fabrication of stretchable conjugated polymer films via solution printing is essential for their practical application in largearea wearable electronics.However,the printed conjugated polymer films typically exhibit high crystallinity,limiting their mechanical deformability.Herein,we propose a plasticizer-assisted printing strategy to simultaneously enhance the stretchability and electrical performance of films based on the conjugated polymer poly(3-(5-(5-methylselenophen-2-yl)thiophen-2-yl)-6-(5-methylthiophen-2-yl)-2,5-bis(4-octyltetradecyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione)(P(TDPP-Se)).The incorporation of a plasticizer trioctyl trimellitate(TOTM)promotes P(TDPP-Se)aggregation in initial solution,facilitates chain alignment under flow field,and shorten solidification process,thereby restricting randomly polymer crystallization.Consequently,a low-crystallinity film with favorable edge-on orientation,strong chain alignment and improved chain dynamics is realized,which effectively alleviates crystallites fragmentation and crack propagation under large strain.The TOTM-plasticized film exhibits approximately 2-fold improvements in fracture strain and charge mobility,along with superior mobility retention under 100%strain in comparison to the neat film.This study provides a feasible approach for microstructure control in printed stretchable conjugated polymer film.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA0540000)the National Natural Science Foundation of China(Nos.22301294,52025031 and 22261142664)the USTC Research Funds of the Double First-Class Initiative(No.YD9990002030)。
文摘Thermosetting polymers exhibit outstanding mechanical properties,thermal stability,and chemical resistance due to their permanently cross-linked network structures.However,the irreversible nature of covalent cross-linking renders these materials non-reprocessable and non-recyclable,posing significant environmental challenges.Although healable polymers based on dynamic covalent bonds and supramolecular interactions have emerged as promising alternatives,a broadly applicable strategy utilizing metal-ligand coordination in thermoset systems remains underexplored.In this work,we present a robust and healable thermoset system fabricated via ring-opening metathesis polymerization(ROMP)of commercially available chelating norbornene comonomers.Cross-linking is accomplished through O-donor coordination to Lewis acidic metal centers,yielding polydicyclopentadiene(PDCPD)-based networks that demonstrate high mechanical strength(up to 60.8 MPa)and effective self-healing performance.This methodology offers a simple and scalable approach to developing high-performance,sustainable thermosetting materials.
基金supported in part by the National Key R&D Program of China under Grant 2024YFB4405300 and 2022YFA1204300the Natural Science Foundation of Hunan Province under Grant 2023JJ20016+2 种基金the National Natural Science Foundation of China under Grants of 52221001 and 62090035the Key Research and Development Plan of Hunan Province under grants of 2022GK3002 and 2023GK2012the Key Program of Science and Technology Department of Hunan Province under grant of 2020XK2001。
文摘Permeable electronics promise improved physiological comfort,but remain constrained by limited functional integration and poor mechanical robustness.Here,we report a three-dimensional(3D)permeable electronic system that overcomes these challenges by combining electrospun SEBS nanofiber mats,high-resolution liquid metal conductors patterned via thermal imprinting(50μm),and a strain isolators(SIL)that protects vertical interconnects(VIAs)from stress concentration.This architecture achieves ultrahigh air permeability(>5.09 m L cm^(-2)min^(-1)),exceptional stretchability(750%fracture strain),and reliable conductivity maintained through more than 32,500 strain cycles.Leveraging these advances,we have integrated multilayer circuits,strain sensors,and a three-axis accelerometer to achieve a fully integrated,stretchable,permeable wireless real-time gesture recognition glove.The system enables accurate sign language interpretation(98%)and seamless robotic hand control,demonstrating its potential for assistive technologies.By uniting comfort,durability,and high-density integration,this work establishes a versatile platform for nextgeneration wearable electronics and interactive human-robot interfaces.
基金supported by the National Natural Science Foundation of China(Nos.T2441002,22525506,U24A20137,and U22A6002)Strategic Priority Research Program of CAS(No.XDB0520101)+1 种基金National Key R&D Program of China(No.2023YFB3609000)CAS Project for Young Scientists in Basic Research(No.YSBR-053)。
文摘The increasing demand for flexible displays and wearable electronics has driven extensive efforts to develop stretchable organic lightemitting diodes(OLEDs).A critical challenge in this field is the creation of emissive layers that combine high efficiency with mechanical robustness.Thermally activated delayed fluorescence(TADF)materials have attracted significant attention as third-generation emitters capable of achieving 100%internal quantum efficiency;however,their application in stretchable OLEDs has been limited.In this study,we propose an elastomer doping strategy.Polyurethane(PU)is incorporated into TADF polymers to improve their mechanical flexibility while maintaining a high luminescent efficiency.The resulting composite films exhibited excellent TADF characteristics and remarkable stretchability(75%).OLEDs fabricated from these materials achieved a maximum external quantum efficiency(EQE)of 14.26%and a peak luminance of 73570 cd·m^(-2),with the PUdoped devices showing a significantly suppressed efficiency roll-off.Additionally,a fully stretchable OLED architecture was designed and operated under tensile strain to maintain stable electroluminescent performance.These results demonstrate that elastomer doping is an effective strategy for balancing the mechanical compliance with optoelectronic performance,offering a promising pathway for the development of high-performance stretchable OLEDs for flexible electronics.
基金supported by Natural Science and Engineering Research Council of Canada(RGPIN-2017-06737)Canada Research Chairs program,the National Key Research and Development Program of China(2017YFD0601005,2022YFD0904201)+1 种基金the National Natural Science Foundation of China(51203075)the China Scholarship Council(Grant No.CSC202208320361).
文摘With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.
基金financially supported by the National Natural Science Foundation of China(Nos.52303239 and 51933001)Natural Science Foundation of Shandong Province(Nos.ZR2022QB141 and 2023HWYQ-087).
文摘Intrinsic stretchability is a promising attribute of polymer organic solar cells(OSCs).However,rigid molecular blocks typically exhibit poor tensile properties,rendering polymers vulnerable to mechanical stress.In this study,we introduce a different approach utilizing all-small-molecule donors and acceptors to fabricate stretchable OSCs.An elastomer,styrene-b-ethylene-butylene-styrene(SEBS),was embedded to modulate film crystallization and stretchability.SEBS effectively confines the growth process of donors and acceptors,leading to enhancement of the crystallization quality,thus contributing to enhanced device efficiencies.Meanwhile,SEBS can absorb and release mechanical stress during stretching,thereby preventing mechanical degradation of donors and acceptors.The mechanical properties of the OSCs were significantly improved by the incorporation of SEBS.Notably,the crack-onset strain increased from 1.03% to 5.99% with SEBS embedding.These findings present a straightforward strategy for achieving stretchable OSCs using all small molecules,offering a different perspective for realizing stretchable devices.
文摘Soft polymer optical fiber(SPOF)has shown great potential in optical-based wearable and implantable biosensors due to its excellent mechanical properties and optical guiding characteristics.However,the multimodality characteristics of SPOF limit their integration with traditional fiber optic sensors.This article introduces for the first time a flexible fiber optic vibration sensor based on laser interference technology,which can be applied to vibration measurement under high stretch conditions.This sensor utilizes elastic optical fibers made of polydimethylsiloxane(PDMS)as sensing elements,combined with phase generating carrier technology,to achieve vibration measurement at 50−260 Hz within the stretch range of 0−42%.
基金supported by the Scientific and Technological Project in Henan Province(242102231002)Henan Province Science and Technology Research and Development Program Joint Fund Advantageous Discipline Cultivation Project(No.232301420033)the Foundation for Outstanding Young Teachers in Universities of Henan Province(2021GGJS014).
文摘Bionic hydrogels offer significant advantages over conventional counterparts,boasting superior properties like enhanced adhesion,stretchability,conductivity,biocompatibility and versatile functionalities.Their physicochemical resemblance to biological tissues makes bionic hydrogels ideal interfaces for bioelectronic devices.In contrast,conventional hydrogels often exhibit inadequate performance,such as easy detachment,lack of good skin compliance,and inadequate conductivity,failing to meet the rigorous demands of bioelectronic applications.Bionic hydrogels,inspired by biological designs,exhibit exceptional physicochemical characteristics that fulfill diverse criteria for bioelectronic applications,driving the advancement of bioelectronic devices.This review first introduces a variety of materials used in the fabrication of bionic hydrogels,including natural polymers,synthetic polymers,and other materials.Then different mechanisms of hydrogel bionics,are categorized into material bionics,structural bionics,and functional bionics based on their bionic approaches.Subsequently,various applications of bionic hydrogels in the field of bioelectronics were introduced,including physiological signal monitoring,tissue engineering,and human-machine interactions.Lastly,the current development and future prospects of bionic hydrogels in bioelectronic devices are summarized.Hopefully,this comprehensive review could inspire advancements in bionic hydrogels for applications in bioelectronic devices.
文摘The Design and manufacturing of a noble piezoresistive pressure sensor(PS) for subtle pressures(<1 kPa) were presented. Meanwhile, in the studies conducted in the field of pressure sensors, the measurement of subtle pressures has received less attention. The limitations in the inherent gauge factor in silicon, have led to the development of polymer and composite resistive sensitive elements. However,in the development of resistance sensing elements, the structure of composite elements with reinforcement core has not been used. The proposed PS had a composite sandwich structure consisting of a nanocomposite graphene layer covered by layers of PDMS at the bottom and on the top coupled with a polyimide(PI) core. Various tests were performed to analyze the PS. The primary design target was improved sensitivity, with a finite-element method(FEM) utilized to simulate the stress profile over piezoresistive elements and membrane deflection at various pressures. The PS manufacturing process is based on Laser-engraved graphene(LEG) technology and PDMS casting. Experimental data indicated that the manufactured PS exhibits a sensitivity of 67.28 mV/kPa for a pressure range of 30-300 Pa in ambient temperature.
基金supported by the National Key Re-search and Development Program of China(No.2021YFA0715700)the National Natural Science Foundation of China(No.52003212).
文摘As a natural biopolymer material,silk fibroin with unique mechanical properties can be used in the preparation of biocomposite hydrogels for strain sensors.But,the electromechanical properties of bio-composite hydrogel strain sensors are still insufficient,such as the deterioration of electrical signals and low sensitivity,which need to develop a hydrogel with a stable transmission network for electric con-duction.Herein,a silk fibroin biocomposite hydrogel is prepared by incorporating tannic acid and MXene nanosheets into a polyacrylamide and silk fibroin double network.The electromechanical properties of hydrogels are improved by optimizing the proportion of material components.As a result,the double network structure and supramolecular interaction enhance the stretchability of hydrogels(692% fracture strain).The hydrogel also exhibits good biocompatibility and conductivity(0.85 S/m),which shows the application prospect in wearable sensors.The wireless strain sensor assembled by this biocomposite hy-drogel presents good portability and sensing performance,such as high sensitivity(gauge factor=6.04),wide working range(500% strain),and outstanding stability(1000 cycles at 100%strain).The results in-dicate that the hydrogel strain sensor can be used to monitor human body movement.The biocomposite hydrogel is expected to be applied in the field of wearable strain sensors,and this study can provide a new way for the design of flexible electronic materials.
基金financial support from National Natural Science Foundation of China(Nos.22005186 and 51877132) was acknowledged。
文摘Flexible and stretchable energy storage devices are highly desirable for wearable electronics,particularly in the emerging fields of smart clothes,medical instruments,and stretchable skin.Lithium metal batteries(LMBs) with high power density and long cycle life are one of the ideal power sources for flexible and stretchable energy storage devices.However,the current LMBs are usually too rigid and bulky to meet the requirements of these devices.The electrolyte is the critical component that determines the energy density and security of flexible and stretchable LMBs.Among various electrolytes,gel polymer electrolytes(GPEs) perform excellent flexibility,safety,and high ionic conductivity compared with traditional liquid electrolytes and solid electrolytes,fulfilling the next generation deformable LMBs.This essay mainly reviews and highlights the recent progress in GPEs for flexible/stretchable LMBs and provides some useful insights for people interested in this field.Additionally,the multifunctional GPEs with self-healing,flame retardant,and temperature tolerance abilities are summarized.Finally,the perspectives and opportunities for flexible and stretchable GPEs are discussed.
基金the Fundamental Research Funds for the Central Universities(No.buctrc202103)the National Natural Science Foundation of China(Nos.52373170,22171019)+1 种基金Beijing Natural Science Foundation(No.2252015),SINOPEC(No.225057)Open Project Program of the State Key Laboratory of Fine Chemicals(No.KF2201,Dalian University of Technology)。
文摘Intrinsically stretchable semiconducting polymers play a vital role in the development of wearable electronics,featuring low-cost,large-area and high-density fabrication.Only single-stage dynamic chemical bond has been widely incorporated into polymer backbones to afford stretchability while multiple dynamic bonds have not been investigated,making a formidable challenge to achieve high stretchability without compromising charge transport properties.Herein,we synthesize a series of stretchable polymer semiconductors incorporating urethane and bipyridine units,which can provide dynamic interconnected polymer network by combination of hydrogen bonds with metal coordination,simultaneously obtaining excellent stretchability and carrier mobilities.Compared with single-stage hydrogen bonds,multiple dynamic chemical bonds constructed by 10% hydrogen bonds and 0.25 equiv.metal coordination endowed the polymer semiconductors with an 58% enhancement in carrier mobility and a two-fold increase in crack-onset strain.Notably,the polymer exhibited stable carrier mobilities parallel to the stretching direction,with 91% of initial values even under 150% strain,which is the unprecedented value for intrinsically stretchable semiconducting polymers without blending of elastomers.Therefore,the introduction of multiple dynamic bonds provides an effective and promising approach for intrinsically stretchable and high-performance polymer semiconductor.
基金financially supported by the Sichuan Provincial Science and Technology Fund for Distinguished Young Scholars,China(Grant No.2022JDJQ0028)Research Startup Fund by Sichuan University,China(Grant No.YJ202218).
文摘Triboelectric nanogenerators(TENGs)are emerging as new technologies to harvest electrical power from mechanical energy.With the distinctive working mechanism of triboelectric nanogenerators,they attract particular interest in healthcare monitoring,wearable electronics,and deformable energy harvesting,which raises the requirement for highly conformable devices with substantial energy outputs.Here,a simple,low-cost strategy for fabricating stretchable triboelectric nanogenerators with ultra-high electrical output is developed.The TENG is prepared using PTFE micron particles(PPTENG),contributing a different electrostatic induction process compared to TENG based on dielectric films,which was associated with the dynamics of particle motions in PP-TENG.The generator achieved an impressive voltage output of 1000 V with a current of 25 lA over a contact area of 40320 mm^(2).Additionally,the TENG exhibits excellent durability with a stretching strain of 500%,and the electrical output performance does not show any significant degradation even after 3000 cycles at a strain of 400%.The unique design of the device provides high conformability and can be used as a self-powered sensor for human motion detection.
基金supported by the National Natural Sci-ence Foundation of China(No.12072325)the Natural Science Foundation of Henan Province(No.20A430028).
文摘Stretchable conductive fibers are essential for the advancement of wearable electronic textiles.However,a significant challenge arises as their conductivity sharply decreases when stretched due to disruptions in electronic transport.Coating fibers with soft liquid metal(LM)has emerged as a promising solution.Despite this,there remains an urgent need to develop methods that enhance LM adhesion to substrates while facilitating efficient electron transport pathways.This study demonstrates a novel Ag-LM conductive network strategy for fabricating a thermoplastic polyurethane/polydopamine/silver-LM(TPU/PDA/Ag-LM)fiber membrane.This membrane exhibits outstanding stretchable electromagnetic interference(EMI)shielding performance and is produced through straightforward electrospinning,electroless depositing,and LM coating and activation.The TPU/PDA/Ag fiber membrane is initially prepared via polydopamineassisted deposition of silver nanoparticles(AgNPs)on electrospun TPU fibers.The presence of AgNPs on the surface of TPU/PDA fibers enhances LM adhesion to the substrate and bridges adjacent LM to establish efficient conductive paths.This interaction benefits from the reactive alloying between AgNPs and LM,where the LM infiltrates the gaps among AgNPs,forming a distinctive LM-Ag alloy layer that uniformly coats the surface of TPU fibers.As anticipated,the unique three-dimensional(3D)interconnected LM-Ag conductive network remains intact during stretching,ensuring strain-invariant conductivity.The fabricated TPU/PDA/Ag-LM fiber membrane demonstrates exceptional EMI shielding effectiveness(SE)of 77.4 dB within the frequency range of 8.2-12.8 GHz and maintains an excellent EMI SE of 37.2 dB under extensive tensile deformation of 300%.Furthermore,the TPU/PDA/Ag-LM fiber membrane shows remarkable mechanical properties and stable Joule heating performance even under significant stretching.
文摘This paper examines the transport analysis,including both heat transfer and mass transfer,in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface.The influence of magnetic fields is also inspected in terms of their physical characteristics.To depict the phenomena of transport,modified versions of both Fick's and Fourier's laws are used.Additionally,the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated.Utilizing a curvilinear coordinate system,the flow problem is formulated as partial differential equations(PDEs)for momentum,concentration,microorganism field,and energy.An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).The effects of significant flow parameters on the pressure and microorganism fields,velocity,oscillation velocity,concentration,and temperature distributions are shown via graphs.Furthermore,the variations in skin friction,mass transfer rate,heat transfer rate,and local motile number due to different involved parameters are presented in tables and are analyzed in detail.Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables increase.It is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase,and it increases with the Schmidt number and the heterogeneous reaction strength parameter.Tabular outcomes show a favorable response of the motile number to advanced values of the Peclet number,the Schmidt number,the microorganism difference parameter,and the bio-convective Lewis number.
基金supported by the National Natural Science Foundation of China(No.61775095)six talent peak innovation team in Jiangsu Province(No.TD-SWYY-009)“Taishan scholars”construction special fund of Shandong Province。
文摘The flourishing development in flexible electronics has provoked intensive research in flexible strain sensors to realize accurate perception acquisition under different external stimuli.However,building hydrogel-based strain sensors with high stretchability and sensitivity remains a great challenge.Herein,MXene nanosheets were composited into polyacrylamide-sodium alginate matrix to construct mechanical robust and sensitive double networked hydrogel strain sensor.The hydrophilic MXene nanosheets formed strong interactions with the polymer matrix and endowed the hydrogel with excellent tensile properties(3150%),compliant mechanical strength(2.03 kPa^(-1)in Young’s Module)and long-lasting stability and fatigue resistance(1000 dynamic cycles under 1,600%strain).Due to the highly oriented MXene-based three dimensional conductive networks,the hydrogel sensor achieved extremely high tensile sensitivity(18.15 in gauge factor)and compression sensitivity(0.38 kPa^(-1)below 3 kPa).MXene hydrogel-based strain sensors also displayed negligible hysteresis in electromechanical performance,typical frequent-independent feature and rapid response time to external stimuli.Moreover,the sensor exhibited accurate response to different scales of human movements,providing potential application in speech recognition,expression recognition and handwriting verification.
基金supported by National Natural Science Foundation of China (NSFC) (No. 61804103)National Key R&D Program of China (No. 2017YFA0205002)+8 种基金Natural Science Foundation of the Jiangsu Higher Education Institutions of China (Nos. 18KJA535001 and 14KJB 150020)Natural Science Foundation of Jiangsu Province of China (Nos. BK20170343 and BK20180242)China Postdoctoral Science Foundation (No. 2017M610346)State Key Laboratory of Silicon Materials, Zhejiang University (No. SKL2018-03)Nantong Municipal Science and Technology Program (No. GY12017001)Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University (KSL201803)supported by Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the 111 ProjectJoint International Research Laboratory of Carbon-Based Functional Materials and Devices
文摘Continuous deforming always leads to the performance degradation of a flexible triboelectric nanogenerator due to the Young’s modulus mismatch of different functional layers.In this work,we fabricated a fiber-shaped stretchable and tailorable triboelectric nanogenerator(FST-TENG)based on the geometric construction of a steel wire as electrode and ingenious selection of silicone rubber as triboelectric layer.Owing to the great robustness and continuous conductivity,the FST-TENGs demonstrate high stability,stretchability,and even tailorability.For a single device with ~6 cm in length and ~3 mm in diameter,the open-circuit voltage of ~59.7 V,transferred charge of ~23.7 nC,short-circuit current of ~2.67 μA and average power of ~2.13 μW can be obtained at 2.5 Hz.By knitting several FST-TENGs to be a fabric or a bracelet,it enables to harvest human motion energy and then to drive a wearable electronic device.Finally,it can also be woven on dorsum of glove to monitor the movements of gesture,which can recognize every single finger,different bending angle,and numbers of bent finger by analyzing voltage signals.
基金support from the National Natural Science Foundation of China(61801525)the Guangdong Basic and Applied Basic Research Foundation(2020A1515010693)+1 种基金the Guangdong Natural Science Funds Grant(2018A030313400),the Science and Technology Program of Guangzhou(201904010456)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(2021qntd09).
文摘With the advent of the 5G era and the rise of the Internet of Things,various sensors have received unprecedented attention,especially wearable and stretchable sensors in the healthcare field.Here,a stretchable,self-healable,self-adhesive,and room-temperature oxygen sensor with excellent repeatability,a full concentration detection range(0-100%),low theoretical limit of detection(5.7 ppm),high sensitivity(0.2%/ppm),good linearity,excellent temperature,and humidity tolerances is fabricated by using polyacrylamide-chitosan(PAM-CS)double network(DN)organohydrogel as a novel transducing material.The PAM-CS DN organohydrogel is transformed from the PAM-CS composite hydrogel using a facile soaking and solvent replacement strategy.Compared with the pristine hydrogel,the DN organohydrogel displays greatly enhanced mechanical strength,moisture retention,freezing resistance,and sensitivity to oxygen.Notably,applying the tensile strain improves both the sensitivity and response speed of the organohydrogel-based oxygen sensor.Furthermore,the response to the same concentration of oxygen before and after self-healing is basically the same.Importantly,we propose an electrochemical reaction mechanism to explain the positive current shift of the oxygen sensor and corroborate this sensing mechanism through rationally designed experiments.The organohydrogel oxygen sensor is used to monitor human respiration in real-time,verifying the feasibility of its practical application.This work provides ideas for fabricating more stretchable,self-healable,self-adhesive,and high-performance gas sensors using ion-conducting organohydrogels.
