Additive manufacturing has rapidly evolved over recent years with the advent of polymer inks and those inks containing novel nanomaterials.The compatibility of polymer inks with nanomaterial inks remains a great chall...Additive manufacturing has rapidly evolved over recent years with the advent of polymer inks and those inks containing novel nanomaterials.The compatibility of polymer inks with nanomaterial inks remains a great challenge.Simple yet effective methods for interface improvement are highly sought-after to significantly enhance the functional and mechanical properties of printed polymer nanocomposites.In this study,we developed and modified a Ti_(3)C_(2) MXene ink with a siloxane surfactant to provide compatibility with a polydimethylsiloxane(PDMS)matrix.The rheology of all the inks was investigated with parameters such as complex modulus and viscosity,confirming a self-supporting ink behaviour,whilst Fourier transform infrared spectroscopy exposed the inks’reaction mechanisms.The modified MXene nanosheets have displayed strong interactions with PDMS over a wide strain amplitude.An electrical conductivity of 6.14×10^(−2) S cm^(−1) was recorded for a stretchable nanocomposite conductor containing the modified MXene ink.The nanocomposite revealed a nearly linear stress-strain relationship and a maximum stress of 0.25 MPa.Within 5%strain,the relative resistance change remained below 35%for up to 100 cycles,suggesting high flexibility,conductivity and mechanical resilience.This study creates a pathway for 3D printing conductive polymer/nanomaterial inks for multifunctional applications such as stretchable electronics and sensors.展开更多
The intensifying energy crisis has made it urgent to develop robust and reli-able next-generation energy systems.Except for conventional large-scale energy sources,the imperceptible and randomly distributed energy emb...The intensifying energy crisis has made it urgent to develop robust and reli-able next-generation energy systems.Except for conventional large-scale energy sources,the imperceptible and randomly distributed energy embedded in daily life awaits comprehensive exploration and utilization.Harnessing the latent energy has the potential to facilitate the further evolution of soft energy sys-tems.Compared with rigid energy devices,flexible energy devices are more convenient and suitable for harvesting and storing energy from dynamic and complex structures such as human skin.Stretchable conductors that are capable of withstanding strain(≫1%)while sustaining stable conductive pathways are prerequisites for realizing flexible electronic energy devices.Therefore,under-standing the characteristics of these conductors and evaluating the feasibility of their fabrication strategies are particularly critical.In this review,various prepa-ration methods for stretchable conductors are carefully classified and analyzed.Furthermore,recent progress in the application of energy harvesting and stor-age based on these conductors is discussed in detail.Finally,the challenges and promising opportunities in the development of stretchable conductors and inte-grated flexible energy devices are highlighted,seeking to inspire their future research directions.展开更多
Copper nanowires （Cu NWs） have attracted increasing attention as building blocks for electronics due to their outstanding electrical properties and low cost. However, organic residues and oxide layers ubiquitously e...Copper nanowires （Cu NWs） have attracted increasing attention as building blocks for electronics due to their outstanding electrical properties and low cost. However, organic residues and oxide layers ubiquitously existing on the surface of Cu NWs impede good inter-wire contact. Commonly used methods such as thermal annealing and acid treatment often lead to nanowire damage. Herein, hydrogen plasma treatment at room temperature has been demonstrated to be effective for simultaneous surface cleaning and selective welding of Cu NWs at junctions. Transparent electrodes with excellent optical-electrical performance （19 ff）-sq-1 @ 90% T） and enhanced stability have been fabricated and integrated into organic solar cells. Besides, Cu NW conductors with superior stretchability and cycling stability under stretching speeds of up to 400 mm-min-＇ can also be produced by the nanowelding process, and the feasibility of their application in stretchable LED circuits has been demonstrated.展开更多
Stretchable electronics that monitor joint activity and treat diseases based on liquid metal could be used in the development of healthcare applications.Such devices can be seamlessly integrated with human skin.Howeve...Stretchable electronics that monitor joint activity and treat diseases based on liquid metal could be used in the development of healthcare applications.Such devices can be seamlessly integrated with human skin.However,most high-precision microstructures and complex patterns are difficult to fabricate due to the limitations of conventional fabrication solutions,resulting in suboptimal performance under practical conditions.Here,a liquid-metal stretchable system utilizing natural leaf veins was reported as microstructures,which was based on a biomimetic concept and utilized an all-solution process for the preparation of complex microstructures.The systems are ultra-high tensile(800%tensile strain),environmentally stable(20 days)and mechanically durable(300-cycle).The system can accurately recognize the wearer's finger bending level as well as simple gesture signals.At the same time,the system acts as a wearable heater,which can realize the fast heating behavior of heating up to 50℃in 3 min under the human body-safe voltage(1.5 V).The tensile stability is demonstrated by the heterogeneous integration of lasers(405 nm)with the system interconnects for a stretchable and wearable light source.展开更多
Stretchable power sources,especially stretchable lithium-ion batteries(LIBs),have attracted increasing attention due to their enormous prospects for powering flexible/wearable electronics.Despite recent advances,it is...Stretchable power sources,especially stretchable lithium-ion batteries(LIBs),have attracted increasing attention due to their enormous prospects for powering flexible/wearable electronics.Despite recent advances,it is still challenging to develop ultra-stretchable LIBs that can withstand large deformation.In particular,stretchable LIBs require an elastic electrolyte as a basic component,while the conductivity of most elastic electrolytes drops sharply during deformation,especially during large deformations.This is why highly stretchable LIBs have not yet been realized until now.As a proof of concept,a super-stretchable LIB with strain up to 1200%is created based on an intrinsically super-stretchable polymer electrolyte as the lithium-ion conductor.The super-stretchable conductive system is constructed by an effective diblock copolymerization strategy via photocuring of vinyl functionalized 2-ureido-4-pyrimidone(VFUpy),an acrylic monomer containing succinonitrile and a lithium salt,achieving high ionic conductivity(3.5×10^(-4)mS cm^(-1)at room temperature(RT))and large deformation(the strain can reach 4560%).The acrylic elastomer containing Li-ion conductive domains can strongly increase the compatibility between the neighboring elastic networks,resulting in high ionic conductivity under ultra-large deformation,while VFUpy increases elasticity modulus(over three times)and electrochemical stability(voltage window reaches 5.3 V)of the prepared polymer conductor.At a strain of up to 1200%,the resulting stretchable LIBs are still sufficient to power LEDs.This study sheds light on the design and development of high-performance intrinsically super-stretchable materials for the advancement of highly elastic energy storage devices for powering flexible/wearable electronics that can endure large deformation.展开更多
Wearable on-skin electrodes or conductors should be vapor permeable,strain-insensitive,isotropically stretchable and stable under cyclic stretching.Various strategies have been proposed to prepare the required conduct...Wearable on-skin electrodes or conductors should be vapor permeable,strain-insensitive,isotropically stretchable and stable under cyclic stretching.Various strategies have been proposed to prepare the required conductors up to now;however,it is a challenge to fabricate them with above properties in a simple manner.In this paper,a highly permeable and stretchable conductor based on electrospun fluorine rubber fiber mat is reported.The fibers are pre-stretched in electric field during electrospinning,and they shrink isotropically by~35-40%in area after being detached from the substrate.The obtained fiber mat conductor demonstrates high stretchability up to~170%,and the resistance changes only 0.8 under 60%strain,which is superior to many other strain-insensitive conductors.The conductor possesses high stability,no cracks or structure damage are observed after washing and cyclic stretching.Moreover,the conductor is vapor permeable with a water vapor transmission rate of~850 g m−2 day−1,which is comparable to the normal water evaporation in ambient conditions,indicating that it would not disturb the sweat evaporation when being used on skin.The conductor is successfully used as stretchable yarns and electromyography(EMG)electrodes,showing high reliability in E-textiles and on-skin applications.展开更多
Ionic skin(I-skin)is an emerging skin-inspired sensor that has received increasing interest for the next-generation wearable electronics.However,profound challenges for I-skin remain in achieving multiple signal respo...Ionic skin(I-skin)is an emerging skin-inspired sensor that has received increasing interest for the next-generation wearable electronics.However,profound challenges for I-skin remain in achieving multiple signal responses(e.g.,strain,pressure,and humidity)and self-healability to fully mimic human skin.Herein,a Fe;ion-coordinated poly(acrylic acid)ionogel(PAIFe)with high stretchability,extreme temperature tolerance,and self-healing capability is prepared by a dynamic ionic cross-linking strategy.The ionic coordination in the PAIFe contributes to the formation of a highly dynamic network,achieving its high-efficient and reliable self-healing performance even at a low temperature of-20℃.Using of 1-butyl-3-methylimidazolium tetrafluoroborate([BMIm][BF^(3+)])as the solvent achieves a widetemperature tolerance of the PAIFe under low and high temperatures.More interestingly,a humidity sensing function is realized in the PAIFe by skillfully utilizing the hygroscopic properties of[BMIm][BF_(4)].The resultant PAIFe is proof-ofconcept demonstrated as a deformation-tolerant ionic conductor in a skin-inspired ionic sensor,showing a variety of sensory capabilities towards compression,strain and humidity.展开更多
Stretchable epidermal electronics allow conformal interactions with the human body for emerging applications in wearable health monitoring and therapy.Stretchable devices are commonly constructed on submillimeter-thic...Stretchable epidermal electronics allow conformal interactions with the human body for emerging applications in wearable health monitoring and therapy.Stretchable devices are commonly constructed on submillimeter-thick elastomer substrates with limited moisture permeability,thereby leading to unpleasant sensations during long-term attachment.Although the ultrathin elastomer membrane may address this problem,the mechanical robustness is essentially lost for direct manipulations and repetitive uses.Here,we report a stretchable,breathable,and washable epidermal electrode of microfoam reinforced ultrathin conductive nanocomposite(MRUCN).The new architecture involves ultrathin conductive silver nanowire nanocomposite features supported on a porous elastomeric microfoam substrate,which exhibits high moisture permeability for pleasant perceptions during epidermal applications.As-prepared epidermal electrodes show excellent electronic conductivity(8440 S·cm^(-1)),high feature resolution(~50μm),decent stretchability,and excellent durability.In addition,the MRUCN retains stable electrical properties during washing to meet the hygiene requirements for repetitive uses.The successful implementation in an integrated electronic patch demonstrates the practical suitability of MRUCN for a broad range of epidermal electronic devices and systems.展开更多
Integrating the topology design and printing method offers a promising methodology to realize large stretchability for interconnects.Herein,eco-friendly and waterbased Ag nanowires(NWs)inks were formulated and used fo...Integrating the topology design and printing method offers a promising methodology to realize large stretchability for interconnects.Herein,eco-friendly and waterbased Ag nanowires(NWs)inks were formulated and used for screen-printing highly stretchable and flexible interconnects on a large area(more than 335 mm x 175 mm).The stretchability of the interconnects was realized by introducing kirigami topology structures.The topology designed models were established to simulate the influence of kirigami patterns on wire compliance and to estimate the maximum stretchability via finite element analysis(FEA).The mechanic mechanism results demonstrate that an increase of the wave numbers results in larger stretchability,and the rectangular type of wave shows better stretchability than the zigzag and sine structures.Comparatively,the electrical and mechanical properties of the interconnects were measured and analyzed,and the experimental results were consistent with FEA.The electric conductivity of the interconnects is stable at^10,427 S cm-1 even after 1000 cycles of 15.83 mm radius bending,280%stretching and 200%twisting-stretching deformation,demonstrating outstanding mechanical reliability of the interconnects.The topology designed interconnects have been applied in stretchable flexible light-emitting diode,indicating their broad application prospects in next-generation stretchable electronics.展开更多
Intrinsically conducting polymers(ICPs),such as polyacetylene,polyaniline,polypyrrole,polythiophene,and poly(3,4-ethylenedioxythiophene)(PEDOT),can have important application in flexible electronics owing to their uni...Intrinsically conducting polymers(ICPs),such as polyacetylene,polyaniline,polypyrrole,polythiophene,and poly(3,4-ethylenedioxythiophene)(PEDOT),can have important application in flexible electronics owing to their unique merits including high conductivity,high mechanical flexibility,low cost,and good biocompatibility.The requirements for their application in flexible electronics include high conductivity and appropriate mechanical properties.The conductivity of some ICPs can be enhanced through a postpolymerization treatment,the so-called“secondary doping.”A conducting polymer film with high conductivity can be used as flexible electrode and even as flexible transparent electrode of optoelectronic devices.The application of ICPs as stretchable electrode requires high mechanical stretchability.The mechanical stretchability of ICPs can be improved through blending with a soft polymer or plasticization.Because of their good biocompatibility,ICPs can be modified as dry electrode for biopotential monitoring and neural interface.In addition,ICPs can be used as the active material of strain sensors for healthcare monitoring,and they can be adopted to monitor food processing,such as the fermentation,steaming,storage,and refreshing of starch-based food because of the resistance variation caused by the food volume change.All these applications of ICPs are covered in this review article.展开更多
基金This work was financially supported by Australian Research Council(No.DP220103275)Research Hub for Graphene Enabled Industry Transformation(No.IH150100003).
文摘Additive manufacturing has rapidly evolved over recent years with the advent of polymer inks and those inks containing novel nanomaterials.The compatibility of polymer inks with nanomaterial inks remains a great challenge.Simple yet effective methods for interface improvement are highly sought-after to significantly enhance the functional and mechanical properties of printed polymer nanocomposites.In this study,we developed and modified a Ti_(3)C_(2) MXene ink with a siloxane surfactant to provide compatibility with a polydimethylsiloxane(PDMS)matrix.The rheology of all the inks was investigated with parameters such as complex modulus and viscosity,confirming a self-supporting ink behaviour,whilst Fourier transform infrared spectroscopy exposed the inks’reaction mechanisms.The modified MXene nanosheets have displayed strong interactions with PDMS over a wide strain amplitude.An electrical conductivity of 6.14×10^(−2) S cm^(−1) was recorded for a stretchable nanocomposite conductor containing the modified MXene ink.The nanocomposite revealed a nearly linear stress-strain relationship and a maximum stress of 0.25 MPa.Within 5%strain,the relative resistance change remained below 35%for up to 100 cycles,suggesting high flexibility,conductivity and mechanical resilience.This study creates a pathway for 3D printing conductive polymer/nanomaterial inks for multifunctional applications such as stretchable electronics and sensors.
文摘The intensifying energy crisis has made it urgent to develop robust and reli-able next-generation energy systems.Except for conventional large-scale energy sources,the imperceptible and randomly distributed energy embedded in daily life awaits comprehensive exploration and utilization.Harnessing the latent energy has the potential to facilitate the further evolution of soft energy sys-tems.Compared with rigid energy devices,flexible energy devices are more convenient and suitable for harvesting and storing energy from dynamic and complex structures such as human skin.Stretchable conductors that are capable of withstanding strain(≫1%)while sustaining stable conductive pathways are prerequisites for realizing flexible electronic energy devices.Therefore,under-standing the characteristics of these conductors and evaluating the feasibility of their fabrication strategies are particularly critical.In this review,various prepa-ration methods for stretchable conductors are carefully classified and analyzed.Furthermore,recent progress in the application of energy harvesting and stor-age based on these conductors is discussed in detail.Finally,the challenges and promising opportunities in the development of stretchable conductors and inte-grated flexible energy devices are highlighted,seeking to inspire their future research directions.
基金This work was financially supported by the National Basic Research Program of China （No. 2012CB932303）, the National Natural Science Foundation of China （No. 61301036）, Shanghai Municipal Natural Science Foundation （No. 13ZR1463600）, and the Innovation Project of Shanghai Institute of Ceramics.
文摘Copper nanowires （Cu NWs） have attracted increasing attention as building blocks for electronics due to their outstanding electrical properties and low cost. However, organic residues and oxide layers ubiquitously existing on the surface of Cu NWs impede good inter-wire contact. Commonly used methods such as thermal annealing and acid treatment often lead to nanowire damage. Herein, hydrogen plasma treatment at room temperature has been demonstrated to be effective for simultaneous surface cleaning and selective welding of Cu NWs at junctions. Transparent electrodes with excellent optical-electrical performance （19 ff）-sq-1 @ 90% T） and enhanced stability have been fabricated and integrated into organic solar cells. Besides, Cu NW conductors with superior stretchability and cycling stability under stretching speeds of up to 400 mm-min-＇ can also be produced by the nanowelding process, and the feasibility of their application in stretchable LED circuits has been demonstrated.
基金financially supported by the National Key Research and Development Program of China(No.2021YFA1401100)the National Natural Science Foundation of China(Nos.61825403 and 61921005)。
文摘Stretchable electronics that monitor joint activity and treat diseases based on liquid metal could be used in the development of healthcare applications.Such devices can be seamlessly integrated with human skin.However,most high-precision microstructures and complex patterns are difficult to fabricate due to the limitations of conventional fabrication solutions,resulting in suboptimal performance under practical conditions.Here,a liquid-metal stretchable system utilizing natural leaf veins was reported as microstructures,which was based on a biomimetic concept and utilized an all-solution process for the preparation of complex microstructures.The systems are ultra-high tensile(800%tensile strain),environmentally stable(20 days)and mechanically durable(300-cycle).The system can accurately recognize the wearer's finger bending level as well as simple gesture signals.At the same time,the system acts as a wearable heater,which can realize the fast heating behavior of heating up to 50℃in 3 min under the human body-safe voltage(1.5 V).The tensile stability is demonstrated by the heterogeneous integration of lasers(405 nm)with the system interconnects for a stretchable and wearable light source.
基金We acknowledge financial support from the National Natural Science Foundation of China(21835003,21674050,91833304,21805136 and 61904084)the National Key Basic Research Program of China(2023YFB3608904,2017YFB0404501 and 2014CB648300)+8 种基金the Natural Science Foundation of Jiangsu Province(BK20210601,BE2019120 and BK20190737)Program for Jiangsu Specially-Appointed Professor(RK030STP15001)the Six Talent Peaks Project of Jiangsu Province(TD-XCL-009)the 333 Project of Jiangsu Province(BRA2017402),the NUPT"1311 Project"and Scientific Foundation(NY219159,NY218164 and NY219020)the Leading Talent of Technological Innovation of National Ten-Thousands Talents Program of China,the Excellent Scientific and Technological Innovative Teams of Jiangsu Higher Education Institutions(TJ217038)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD,YX030003)Special Fund of"Jiangsu Provincial High-level Innovative and Entrepreneurial Talents Introduction Program"(the first batch)in 2020(Doctoral Aggregation Program)(CZ030SC20016)China Postdoctoral Science Foundation(2021M691652)Jiangsu Province Postdoctoral Science Foundation(2021K323C).
文摘Stretchable power sources,especially stretchable lithium-ion batteries(LIBs),have attracted increasing attention due to their enormous prospects for powering flexible/wearable electronics.Despite recent advances,it is still challenging to develop ultra-stretchable LIBs that can withstand large deformation.In particular,stretchable LIBs require an elastic electrolyte as a basic component,while the conductivity of most elastic electrolytes drops sharply during deformation,especially during large deformations.This is why highly stretchable LIBs have not yet been realized until now.As a proof of concept,a super-stretchable LIB with strain up to 1200%is created based on an intrinsically super-stretchable polymer electrolyte as the lithium-ion conductor.The super-stretchable conductive system is constructed by an effective diblock copolymerization strategy via photocuring of vinyl functionalized 2-ureido-4-pyrimidone(VFUpy),an acrylic monomer containing succinonitrile and a lithium salt,achieving high ionic conductivity(3.5×10^(-4)mS cm^(-1)at room temperature(RT))and large deformation(the strain can reach 4560%).The acrylic elastomer containing Li-ion conductive domains can strongly increase the compatibility between the neighboring elastic networks,resulting in high ionic conductivity under ultra-large deformation,while VFUpy increases elasticity modulus(over three times)and electrochemical stability(voltage window reaches 5.3 V)of the prepared polymer conductor.At a strain of up to 1200%,the resulting stretchable LIBs are still sufficient to power LEDs.This study sheds light on the design and development of high-performance intrinsically super-stretchable materials for the advancement of highly elastic energy storage devices for powering flexible/wearable electronics that can endure large deformation.
基金supported by the Project funded by China Postdoctoral Science Foundation(2020M682987)the NSFC-Shenzhen Robotics Basic Research Center Program(U2013207)+2 种基金the National Natural Science Foundation of China(U1913601,81927804,62003331)the Natural Science Foundation of Guangdong Province(2018A030313065)the National Key Research and Development Project,MOST(2020YFC2005803).
文摘Wearable on-skin electrodes or conductors should be vapor permeable,strain-insensitive,isotropically stretchable and stable under cyclic stretching.Various strategies have been proposed to prepare the required conductors up to now;however,it is a challenge to fabricate them with above properties in a simple manner.In this paper,a highly permeable and stretchable conductor based on electrospun fluorine rubber fiber mat is reported.The fibers are pre-stretched in electric field during electrospinning,and they shrink isotropically by~35-40%in area after being detached from the substrate.The obtained fiber mat conductor demonstrates high stretchability up to~170%,and the resistance changes only 0.8 under 60%strain,which is superior to many other strain-insensitive conductors.The conductor possesses high stability,no cracks or structure damage are observed after washing and cyclic stretching.Moreover,the conductor is vapor permeable with a water vapor transmission rate of~850 g m−2 day−1,which is comparable to the normal water evaporation in ambient conditions,indicating that it would not disturb the sweat evaporation when being used on skin.The conductor is successfully used as stretchable yarns and electromyography(EMG)electrodes,showing high reliability in E-textiles and on-skin applications.
基金financially supported by the National Natural Science Foundation of China(21875033 and 52122303)。
文摘Ionic skin(I-skin)is an emerging skin-inspired sensor that has received increasing interest for the next-generation wearable electronics.However,profound challenges for I-skin remain in achieving multiple signal responses(e.g.,strain,pressure,and humidity)and self-healability to fully mimic human skin.Herein,a Fe;ion-coordinated poly(acrylic acid)ionogel(PAIFe)with high stretchability,extreme temperature tolerance,and self-healing capability is prepared by a dynamic ionic cross-linking strategy.The ionic coordination in the PAIFe contributes to the formation of a highly dynamic network,achieving its high-efficient and reliable self-healing performance even at a low temperature of-20℃.Using of 1-butyl-3-methylimidazolium tetrafluoroborate([BMIm][BF^(3+)])as the solvent achieves a widetemperature tolerance of the PAIFe under low and high temperatures.More interestingly,a humidity sensing function is realized in the PAIFe by skillfully utilizing the hygroscopic properties of[BMIm][BF_(4)].The resultant PAIFe is proof-ofconcept demonstrated as a deformation-tolerant ionic conductor in a skin-inspired ionic sensor,showing a variety of sensory capabilities towards compression,strain and humidity.
基金This work was supported by Key Research and Development Program of Jiangsu Provincial Department of Science and Technology of China(No.BE2019002)Key Research and Development Program of Hebei Provence(No.19251804D)High-Level Entrepreneurial and Innovative Talents Program of Jiangsu Province。
文摘Stretchable epidermal electronics allow conformal interactions with the human body for emerging applications in wearable health monitoring and therapy.Stretchable devices are commonly constructed on submillimeter-thick elastomer substrates with limited moisture permeability,thereby leading to unpleasant sensations during long-term attachment.Although the ultrathin elastomer membrane may address this problem,the mechanical robustness is essentially lost for direct manipulations and repetitive uses.Here,we report a stretchable,breathable,and washable epidermal electrode of microfoam reinforced ultrathin conductive nanocomposite(MRUCN).The new architecture involves ultrathin conductive silver nanowire nanocomposite features supported on a porous elastomeric microfoam substrate,which exhibits high moisture permeability for pleasant perceptions during epidermal applications.As-prepared epidermal electrodes show excellent electronic conductivity(8440 S·cm^(-1)),high feature resolution(~50μm),decent stretchability,and excellent durability.In addition,the MRUCN retains stable electrical properties during washing to meet the hygiene requirements for repetitive uses.The successful implementation in an integrated electronic patch demonstrates the practical suitability of MRUCN for a broad range of epidermal electronic devices and systems.
基金supported by the National Natural Science Foundation of China(51471121)the Basic Research Plan Program of Shenzhen City(JCYJ20170303170426117)+2 种基金the Natural Science Foundation of Jiangsu Province(BK20160383)the Fundamental Research Funds for the Central Universities(2042018kf203)Wuhan University
文摘Integrating the topology design and printing method offers a promising methodology to realize large stretchability for interconnects.Herein,eco-friendly and waterbased Ag nanowires(NWs)inks were formulated and used for screen-printing highly stretchable and flexible interconnects on a large area(more than 335 mm x 175 mm).The stretchability of the interconnects was realized by introducing kirigami topology structures.The topology designed models were established to simulate the influence of kirigami patterns on wire compliance and to estimate the maximum stretchability via finite element analysis(FEA).The mechanic mechanism results demonstrate that an increase of the wave numbers results in larger stretchability,and the rectangular type of wave shows better stretchability than the zigzag and sine structures.Comparatively,the electrical and mechanical properties of the interconnects were measured and analyzed,and the experimental results were consistent with FEA.The electric conductivity of the interconnects is stable at^10,427 S cm-1 even after 1000 cycles of 15.83 mm radius bending,280%stretching and 200%twisting-stretching deformation,demonstrating outstanding mechanical reliability of the interconnects.The topology designed interconnects have been applied in stretchable flexible light-emitting diode,indicating their broad application prospects in next-generation stretchable electronics.
基金grateful to the Ministry of Education of Singapore for the research grant of R-284-000-197-114.
文摘Intrinsically conducting polymers(ICPs),such as polyacetylene,polyaniline,polypyrrole,polythiophene,and poly(3,4-ethylenedioxythiophene)(PEDOT),can have important application in flexible electronics owing to their unique merits including high conductivity,high mechanical flexibility,low cost,and good biocompatibility.The requirements for their application in flexible electronics include high conductivity and appropriate mechanical properties.The conductivity of some ICPs can be enhanced through a postpolymerization treatment,the so-called“secondary doping.”A conducting polymer film with high conductivity can be used as flexible electrode and even as flexible transparent electrode of optoelectronic devices.The application of ICPs as stretchable electrode requires high mechanical stretchability.The mechanical stretchability of ICPs can be improved through blending with a soft polymer or plasticization.Because of their good biocompatibility,ICPs can be modified as dry electrode for biopotential monitoring and neural interface.In addition,ICPs can be used as the active material of strain sensors for healthcare monitoring,and they can be adopted to monitor food processing,such as the fermentation,steaming,storage,and refreshing of starch-based food because of the resistance variation caused by the food volume change.All these applications of ICPs are covered in this review article.
