Driven by the burgeoning demand for wearable electronics,the development of inherently safe,mechanically compliant,and high-energy–density power sources has become imperative.Flexible aqueous Zn ions batteries(FAZIBs...Driven by the burgeoning demand for wearable electronics,the development of inherently safe,mechanically compliant,and high-energy–density power sources has become imperative.Flexible aqueous Zn ions batteries(FAZIBs)are hampered by Zn dendrite formation and hydrogen evolution,underscoring the urgent need for highly stable and novel flexible energy-storage devices.Although flexible aqueous cobalt-ion batteries(FACIBs)employing cobalt-salt aqueous electrolytes exhibit high theoretical capacity,they suffer from two limitations:the rapid dissolution of cathode active substances in the aqueous electrolyte and the risk of liquid electrolyte leakage under mechanical deformation.Here,we report the first realization of an ultra-stable,quasi-solid-state and mechanically FACIBs.Polyacrylamide(PAM)containing CoSO_(4) serves as the quasi-solid electrolyte,while cobalt hexacyanoferrate(CoHCF)functions as the cathode active material,and metallic cobalt foil as the flexible anode.This configuration simultaneously eliminates electrolyte leakage and suppresses the dissolution of CoHCF due to the common-ion effect of Co^(2+).Consequently,the fabricated FACIBs exhibit extraordinary cycling durability and remarkable mechanical robustness(95.9%retention after 500 bending cycles).Thus,this work provides a new way for designing ultra-stable energy storage devices for wearable electronics.展开更多
For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of e...For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of electrical conductivity and structural stability in the electrode materials during electrochemical cycling.We report the production of a novel flexible electrode material,by anchoring MnO_(2) nanosheets on a B,N co-doped carbon nanotube ar-ray(BNCNTs)grown on carbon cloth(BNCNTs@MnO_(2)),which was fabricated by in-situ pyrolysis and hydrothermal growth.The generated BNCNTs were strongly bonded to the surface of the car-bon fibers in the carbon cloth which provides both excellent elec-tron transport and ion diffusion,and improves the stability and dur-ability of the cathode.Importantly,the BNCNTs offer more active sites for the hydrothermal growth of MnO_(2),ensuring a uniform dis-tribution.Electrochemical tests show that BNCNTs@MnO_(2) delivers a high specific capacity of 310.7 mAh g^(−1) at 0.1 A g^(−1),along with excellent rate capability and outstanding cycling stability,with a 79.7% capacity retention after 8000 cycles at 3 A g^(−1).展开更多
Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in ...Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in scalable flexible fabrication.In this study,a high-stability fluorescent ink was developed by incorporating QDs into a polydimethylsiloxane(PDMS)colloidal matrix.High-performance patterned films were then obtained via systematic optimization of screen-printing parameters,with film quality governed by substrate type(131μm PDMS),QD concentration(1.5 mg/mL),and screen mesh count(420 mesh).The optimized films exhibit outstanding environmental and photostability,retaining 75.6% of their fluorescence intensity after immersion in deionized water and 63.8% in 75%ethanol at 25℃ for 100 minutes.Under UV irradiation(365 nm,9 W,100 min),fluorescence intensity decreases by less than 20%.Utilizing their daylight transparency and UV-excitable luminescence,various patterns including QR codes and Code 93 standard barcodes were fabricated via screen printing with high pattern fidelity and machine readability.This study presents a scalable and reliable strategy for the fabrication of flexible,high-stability fluorescent films,supporting their integration into next-generation optoelectronic devices,advanced displays,and secure anti-counterfeiting.展开更多
Flexible polymer electronics have emerged as an important research frontier in materials science due to their unique advantages,including mechanical flexibility,lightweight characteristics,and solution processability....Flexible polymer electronics have emerged as an important research frontier in materials science due to their unique advantages,including mechanical flexibility,lightweight characteristics,and solution processability.These features enable a wide range of emerging applications such as wearable electronics,electronic skins,and biomedical devices,etc.In recent years,much advances in polymer chemistry,device physics,and interface engineering have significantly improved the performance of flexible polymer electronic devices,accelerating their transition from fundamental research to practical applications.展开更多
Cellulose,the dominant natural polymer on Earth,features a distinct molecular structure with extraordinary mechanical properties and tunable characteristics,making it attractive for gel systems.Although significant pr...Cellulose,the dominant natural polymer on Earth,features a distinct molecular structure with extraordinary mechanical properties and tunable characteristics,making it attractive for gel systems.Although significant progress has been made,challenges remain in fully leveraging their functional potential and broadening practical applications.This review systematically examines the properties of cellulose and cellulose gels,exploring novel reinforcement strategies—across molecular,supramolecular network,and macroscale structure levels—to enhance mechanical,electrical,and thermal performance,while coordinating these properties for practical implementations.These advancements are exemplified in emerging fields such as flexible robotics,electronic skins,flexible energy storage devices,and human-machine interaction systems.This article thoroughly investigates the fundamental characteristics,multi-scale design approaches,performance enhancement mechanisms,and cutting-edge implementations of cellulose-based gels across diverse domains.It provides a comprehensive overview of these advanced materials and offers strategic insights and recommendations for future research and innovation.展开更多
Improving the optoelectronic behavior and stress-deformation stability of conjugated materials is crucial for the realization of their potential applications in flexible optoelectronics.To tune the emission behavior a...Improving the optoelectronic behavior and stress-deformation stability of conjugated materials is crucial for the realization of their potential applications in flexible optoelectronics.To tune the emission behavior and mechanical property of molecular crystals simultaneously via supramolecular salt strategy is rarely reported,which is very important to improve their photophysical behavior and softness for the fabrication of flexible light-emitting device.Herein,supramolecular salt approach has been successfully applied to synthesize two elastic organic fluorescent crystals(CMOH-Py-Cl and CMOH-Py-Br)derived from non-emissive and brittle pyridine-substituted coumarin derivative(CMOH-Py).Their elastic properties can be attributed to the prevalent presence of numerous weak interactions introduced by halogen atoms,which are beneficial to the absorption and release of mechanical energy.Furthermore,density functional theory(DFT)calculations demonstrated a narrowing of the HOMO-LUMO energy gaps from CMOH-Py to CMOH-Py-Cl/CMOH-Py-Br via supramolecular salt approach.Finally,the application of flexible crystal materials in the field of optical waveguides has been investigated.The transformation of crystals in terms of photophysical and mechanical properties,achieved by the supramolecular salt approach,offers novel insights into the design and construction of flexible crystalline materials,providing a new path for the development of next-generation smart materials.展开更多
The increasing pursuit of ultra-high resolution displays has driven the demand for thin film transistors(TFTs)with higher mobility,especially on flexible substrates.In this work,we developed indium tin oxide(ITO)TFTs ...The increasing pursuit of ultra-high resolution displays has driven the demand for thin film transistors(TFTs)with higher mobility,especially on flexible substrates.In this work,we developed indium tin oxide(ITO)TFTs on flexible substrates for the first time and achieved a remarkable average mobility of 39.1 cm^(2)·V^(-1)·s^(-1),via mass-production compatible processes uti-lizing SiO_(2)gate dielectric.Benefiting from the ultra-flat surface and extremely low coefficient of thermal expansion(CTE)of our PI substrate,the ITO TFTs exhibit excellent large-scale uniformity.Additionally,the TFTs generate minor variations of-5.5%and+0.45 V in mobility and threshold voltage under a bending radius of 7 mm,respectively.They stay fully functional even after a dynamic bending test up to 13000 cycles,observing no obvious degradation in mobility and threshold voltage.The reliable mechanical flexibility and robust bending durability demonstrate their great potential for ultra-high resolution flexible displays in the future.展开更多
Health monitoring is becoming increasingly critical for disease prevention,early diagnosis,and highquality living.Polymeric materials,with their mechanical flexibility,biocompatibility,and tunable biochemical properti...Health monitoring is becoming increasingly critical for disease prevention,early diagnosis,and highquality living.Polymeric materials,with their mechanical flexibility,biocompatibility,and tunable biochemical properties,offer unique advantages for creating next-generation personalized devices.In recent years,flexible polymer-based platforms have shown remarkable potential to capture diverse physiological signals in both daily and clinical contexts,including electrophysiological,biochemical,mechanical,and thermal indicators.In this review,we introduce a safety-leveloriented framework to evaluate material and device strategies for health monitoring,spanning the continuum from noninvasive wearables to deeply embedded implants.Physiological signals are systematically classified by use case,and application-specific requirements such as stability,comfort,and long-term compatibility are highlighted as critical factors guiding the selection of polymers,interfacial designs,and device architectures.Special emphasis is placed on mapping material types—including hydrogels,elastomers,and conductive composites—to their most suitable applications.Finally,we propose design principles for developing safe,functional,and adaptive polymer-based systems,aiming at reliable integration with the human body and enabling personalized,preventive healthcare.展开更多
The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precis...The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness.展开更多
Since the first design of tactile sensors was proposed by Harmon in 1982,tactile sensors have evolved through four key phases:industrial applications(1980s,basic pressure detection),miniaturization via MEMS(1990s),fle...Since the first design of tactile sensors was proposed by Harmon in 1982,tactile sensors have evolved through four key phases:industrial applications(1980s,basic pressure detection),miniaturization via MEMS(1990s),flexible electronics(2010s,stretchable materials),and intelligent systems(2020s-present,AI-driven multimodal sensing).With the innovation of material,processing techniques,and multimodal fusion of stimuli,the application of tactile sensors has been continuously expanding to a diversity of areas,including but not limited to medical care,aerospace,sports and intelligent robots.Currently,researchers are dedicated to develop tactile sensors with emerging mechanisms and structures,pursuing high-sensitivity,high-resolution,and multimodal characteristics and further constructing tactile systems which imitate and approach the performance of human organs.However,challenges in the combination between the theoretical research and the practical applications are still significant.There is a lack of comprehensive understanding in the state of the art of such knowledge transferring from academic work to technical products.Scaled-up production of laboratory materials faces fatal challenges like high costs,small scale,and inconsistent quality.Ambient factors,such as temperature,humidity,and electromagnetic interference,also impair signal reliability.Moreover,tactile sensors must operate across a wide pressure range(0.1 k Pa to several or even dozens of MPa)to meet diverse application needs.Meanwhile,the existing algorithms,data models and sensing systems commonly reveal insufficient precision as well as undesired robustness in data processing,and there is a realistic gap between the designed and the demanded system response speed.In this review,oriented by the design requirements of intelligent tactile sensing systems,we summarize the common sensing mechanisms,inspired structures,key performance,and optimizing strategies,followed by a brief overview of the recent advances in the perspectives of system integration and algorithm implementation,and the possible roadmap of future development of tactile sensors,providing a forward-looking as well as critical discussions in the future industrial applications of flexible tactile sensors.展开更多
The energy transition inspired by carbon neutrality targets and the increasing threat of extreme events raise multi-objective development requirements for power systems.This paper proposes a multi-objective resource a...The energy transition inspired by carbon neutrality targets and the increasing threat of extreme events raise multi-objective development requirements for power systems.This paper proposes a multi-objective resource allocation model to determine the type,number and location of flexible resources to increase the values of resilience,carbon reduction and renewable energy consumption.To evaluate the values of resilience,a restoration model for transmission systems is established that considers the coordination of fossil-fuel generators,energy storage systems(ESSs)and renewable energy generators in building restoration paths.The collaborative power-carbon-tradable green certificate(TGC)market model is then applied to evaluate the resource values in terms of carbon reduction and renewable energy consumption.Finally,the model is formulated as a mixed-integer linear programming(MILP)with a nonconvex feasible domain,and the normalized normal constraint(NNC)method is applied to obtain approximate Pareto frontiers for decision makers.Case studies validate the effectiveness of the proposed model in improving multi-factor values and analyze the impact of resource regulation capacity on values of restoration and carbon reduction.展开更多
The advancement of flexible memristors has significantly promoted the development of wearable electronic for emerging neuromorphic computing applications.Inspired by in-memory computing architecture of human brain,fle...The advancement of flexible memristors has significantly promoted the development of wearable electronic for emerging neuromorphic computing applications.Inspired by in-memory computing architecture of human brain,flexible memristors exhibit great application potential in emulating artificial synapses for highefficiency and low power consumption neuromorphic computing.This paper provides comprehensive overview of flexible memristors from perspectives of development history,material system,device structure,mechanical deformation method,device performance analysis,stress simulation during deformation,and neuromorphic computing applications.The recent advances in flexible electronics are summarized,including single device,device array and integration.The challenges and future perspectives of flexible memristor for neuromorphic computing are discussed deeply,paving the way for constructing wearable smart electronics and applications in large-scale neuromorphic computing and high-order intelligent robotics.展开更多
The demand for sensors capable of operating in extreme environment of the fields,such as aerospace vehicles,aeroengines and fire protection,is rapidly increasing.However,developing flexible ceramic fibrous pressure se...The demand for sensors capable of operating in extreme environment of the fields,such as aerospace vehicles,aeroengines and fire protection,is rapidly increasing.However,developing flexible ceramic fibrous pressure sensors that combine high temperature stability with robust mechanical properties remains a significant challenge.Herein,through precise multi-scale process control,high-strength(2.1 MPa)TiC-SiC flexible fibrous membrane is successfully fabricated.The membrane exhibits exceptional thermal resistance(2000℃)and long–term thermal stability(1800℃ for 5 h)in the inert atmosphere.Meanwhile,the TiC-SiC fibrous membrane shows excellent oxidation resistance and still achieves strength of 1.8 MPa after being oxidized at 1200℃ for 1 h in air.Remarkably,TiC-SiC fibrous membrane withstands a load of approximately 1400 times its own weight and the ablation of butane flame(~1300℃)for at least 1 h without breaking.Notably,after heat treatment at 1800℃ for 5 h in an argon atmosphere,the TiC-SiC fibrous membrane even sustains pressure–sensing performance for up to 300 cycles.The membrane exhibits stable resistivity up to 900℃ and shows sensing stability under butane flame.The results of this work provide an effective and feasible solution to fill the research gap of flexible fibrous sensors for extreme environments.展开更多
MnO_(2) emerges as a promising cathode material for aqueous zinc-ion batteries(AZIBs)due to its high theoretical capacity and ideal working voltage.However,inherent limitations in low electrical conductivity and struc...MnO_(2) emerges as a promising cathode material for aqueous zinc-ion batteries(AZIBs)due to its high theoretical capacity and ideal working voltage.However,inherent limitations in low electrical conductivity and structural instability restrict its widespread application.Herein,we fabricated layered δ-MnO_(2) and introduced Cu and Ce metal ions for structural regulation,thus constructing a δ/a-MnO_(2) heterostructure within the δ-MnO_(2) matrix,forming a heterointerface that simultaneously enhances the electrical conductivity and structural stability of the material.In this system,Cu^(2+)acts as a catalyst,promoting the reduction of high-valent Mn to Mn^(2+)and enabling local two-electron transfer,which significantly increases the discharge specific capacity of MnO_(2).For Ce^(3+),it functions as a structural regulator,inducing the partial transformation of δ-MnO_(2) to a-MnO_(2) and forming the δ/a-MnO_(2) heterostructure.Further supported by density functional theory(DFT)calculations and in-situ characterization results,the heterointerface between a-MnO_(2) andδ-MnO_(2) generates an internal electric field due to the difference in Fermi levels.This not only effectively enhances the electron transfer capability but also significantly improves structural stability.Benefiting from these advantages,the Cu,Ce co-incorporated MnO_(2)(CCMO)cathode delivers a high discharge capacity of 455.4 mAh g^(-1)at 0.2 A g^(-1)and maintains 191.2 mAh g^(-1)specific capacity after 1500 cycles with 95%capacity retention at 2 A g^(-1),which is significantly better than non-doped MnO_(2).This strategy of structural regulation and heterostructure construction using vip ions offers a new approach for developing high-performance Mn-based cathode materials for AZIBs.展开更多
Photo-assisted flexible energy storage devices,combining photoelectric conversion and electrochemical energy storage,emerge as an innovative solution for sustainable energy systems.This review comprehensively summariz...Photo-assisted flexible energy storage devices,combining photoelectric conversion and electrochemical energy storage,emerge as an innovative solution for sustainable energy systems.This review comprehensively summarizes recent advances in photo-assisted flexible energy storage technology,covering material design,working mechanisms,and practical applications.We systematically examine diverse electrode materials,such as metal oxides,metal sulfides,organic photosensitive materials,and composites,emphasizing their roles in boosting device performance.Special focus is placed on emerging technologies—including heterostructure engineering,surface modification,and intelligent control systems—that have notably enhanced energy conversion efficiency and storage capacity.The review also discusses current challenges,such as material stability,conversion efficiency,and standardization,and proposes strategic directions for future development.Recent breakthroughs in photo-assisted supercapacitors,lithium-based batteries,zinc-based batteries,and other innovative storage systems are critically assessed,offering key insights into their practical application potential in wearable electronics,self-powered sensors,and beyond.This comprehensive analysis establishes a framework for understanding the current status of photo-assisted flexible energy storage technology and guides future research toward high-performance,sustainable energy storage solutions.展开更多
Conducting hydrogels have garnered significant interest in the field of wearable electronics.However,simultaneously achieving high transparency,high conductivity,strong adhesion,and self-healing ability within a short...Conducting hydrogels have garnered significant interest in the field of wearable electronics.However,simultaneously achieving high transparency,high conductivity,strong adhesion,and self-healing ability within a short time remains a major challenge.In this study,a multifunctional mussel-inspired hydrogel was synthesized in only 5 min,with polydopamine(PDA)-polypyrrole(Ppy)-polyaniline(PANi)and poly(vinyl alcohol)(PVA)nanoparticles incorporated into the polyacrylamide(PAM)network.The resulting hydrogel exhibited high transparency(about 90% light transmission in the range of 400-800 nm),high conductivity((95.4±0.4)×10^(-4)S/cm),tensile strength(32.60±1.03 k Pa),strain at break(904.46%±11.50%),and adhesive strength(30-60 k Pa).It also demonstrated rapid self-healing properties(about 48% strength recovery within 1h at 50℃)and water-dependent shape memory behavior.As a wearable strain sensor,the hydrogel successfully detected finger flexion,wrist movements,facial expression changes,and breathing with high sensitivity and stability.The calculated gauge factor(GF)was 7.44±0.31,which is higher than that of many previously reported hydrogels.Compared with previous oyster-inspired or Ppy-based hydrogels,our system showed a much shorter synthesis time,higher transparency,and enhanced multifunctionality.These findings highlight the potential of the proposed hydrogel for next-generation flexible electronics,e-skin,and biomedical monitoring devices.展开更多
This study presents a systematic investigation of high-efficiency flexible copper indium gallium selenide(CIGS)thin-film solar cells fabricated using an optimized three-stage co-evaporation process.The research focuse...This study presents a systematic investigation of high-efficiency flexible copper indium gallium selenide(CIGS)thin-film solar cells fabricated using an optimized three-stage co-evaporation process.The research focuses on two key innovations:(1)NaF pre-deposition for controlled alkali metal doping and(2)active regulation of In/Ga evaporation timing during the initial growth stage to precisely engineer the Ga/(Ga+In)(GGI)ratio gradient throughout the absorber layer depth.Through comprehensive characterization of structural properties,elemental distributions,and device performance,we demonstrate that the synergistic combination of Na doping and tailored Ga grading effectively addresses critical challenges in flexible CIGS devices,including back-surface Ga accumulation and non-ideal bandgap profiles.Our results reveal that this dual optimization strategy significantly enhances charge carrier mobility and collection efficiency,ultimately leading to substantial improvements in overall solar cell performance.The findings establish a robust materials engineering approach for developing high-performance flexible photovoltaic devices through precise control of compositional gradients and defect passivation.展开更多
The development of high-performance transparent substrates is critical for next-generation flexible electronic devices.Herein,we designed two novel meta-substituted diamines incorporating trifluoromethyl(―CF_(3))and ...The development of high-performance transparent substrates is critical for next-generation flexible electronic devices.Herein,we designed two novel meta-substituted diamines incorporating trifluoromethyl(―CF_(3))and methyl(―CH_(3))groups to synthesize colorless copolyimide(CPI)films via copolymerization with 4,4′-(hexafluoroisopropylidene)diphthalic anhydride(6FDA)/3,3′,4,4′-biphenyltetracarboxylic dianhydride(BPDA).The combination of meta-substituted architecture and substituents enables the simultaneous attainment of an ultralow dielectric constant(D_k)and high transparency.The meta-substitution geometry and electronic effects of―CF_(3)/―CH_(3) effectively suppressed charge-transfer complex(CTC)formation,expanded fractional free volume(FFV),and restricted π-electron conjugation,as validated by DFT calculations and wide-angle X-ray diffraction(WAXD)analysis.The optimized CPI film(PIA_(1)-6FDA/BPDA(10/0))achieved outstanding transmittance(T_(450)=88.15%),ultralow dielectric constant(D_(k)=2.08 at 1 k Hz),and minimal dielectric loss(D_(f)=0.0012),while maintaining robust thermal stability(T_(d5%)>523℃)and mechanical strength(σ=87.5 MPa).This work establishes a molecular engineering strategy to concurrently enhance the optical and dielectric properties,positioning meta-substituted CPIs as promising candidates for transparent flexible devices.展开更多
The demand for sustainable energy storage has accelerated the development of cellulose-based materials(CBMs)for flexible supercapacitors(FSCs).However,widespread commercialization of FSCs remains challenged by their l...The demand for sustainable energy storage has accelerated the development of cellulose-based materials(CBMs)for flexible supercapacitors(FSCs).However,widespread commercialization of FSCs remains challenged by their low gravimetric energy density(approximately 35 Wh kg^(-1)),far below lithium-ion batteries(exceeding 200 Wh kg^(-1)),and a limited operational temperature range(from-20℃ to 60℃),restricting their use in extreme environments.To date,no comprehensive review has elucidated the crucial role of the chemistry and structure-property relationships of CBMs in advancing FSC technology.This review fills this gap by examining the chemical attributes and versatility of cellulose and its derivatives,including their physicochemical characteris-tics,assembly methodologies,and functional modifications such as oxidation,esterification,etherification,grafting polymerization,nucleophilic substitution,and crosslinking reactions.We further provide an overview of the chemistry and structure-function correlations of various cellulose forms used in advanced electrodes,solid electrolytes,separators,binders,current collectors,and substrate/encapsulation materials,alongside relevant microelectrode processing technologies.Given that large-scale application of FSCs is still in its early stages,we offer insightful design principles for guiding future development of cellulose-based FSCs.By proposing a“chemistry-performance-sustainability”design framework,this review not only addresses existing limitations but also outlines a roadmap for next-generation eco-friendly FSCs.展开更多
Temperature stability is essential for the precision of flexible sensors.However,constrained by the composite principle of heterogeneous materials,the existing self-compensating methods encounter substantial challenge...Temperature stability is essential for the precision of flexible sensors.However,constrained by the composite principle of heterogeneous materials,the existing self-compensating methods encounter substantial challenges.To tackle this,high-entropy alloy nanofibers were utilized to construct a flexible strain sensor with inherent temperature stability.This approach leverages the electrohydrodynamic direct writing;a precursor conductive network was established through the electrospinning of a high-entropy alloy acetate and polyvinylidene difluoride solution blend.Subsequently,annealing treatment facilitated metallization,resulting in the synergistic preservation of polymer stretchability and the low temperature coefficient of resistance properties of high-entropy alloys inside the nanofibers.The test results demonstrate that the high-entropy alloys flexible strain sensor exhibits a remarkably low temperature coefficient of resistance(45.59 ppm K^(-1))across the range of-10 to 70℃,a sensitivity coefficient GF of 1.12 with a 50%strain range,and a response time of 310 ms.After 6000 stretching cycles,no baseline drift or failure occurred,indicating excellent cyclic stability.Furthermore,the outstanding temperature stability of the sensor was validated through wearable application and robotic hands strain sensing conducted under varied environment temperatures.This work provides a viable design pathway for developing flexible sensors with an inherently low temperature coefficient of resistance.展开更多
基金supported by the National Natural Science Foundation of China(52402040 and 52561160149)National Key R&D Program of China(2024YFE0109200)+7 种基金Fundamental Research Funds for the Central Universities(2024300440)Open Project(M37033)of National Laboratory of Solid State Microstructures,Nanjing UniversityGuangdong Basic and Applied Basic Research Foundation(2025A1515011098)Shenzhen Science and Technology Program(JCYJ20250604190115021)Key Research Project of Universities in Henan Province(25A430006)Henan Province University Students Innovation Training Project(202510479001)Funded by the Training Program for Young Backbone Teachers in Higher Education Institutions of Henan Province(Prof.Chaowei Li)Science and Technology Research Project of Henan Province(242102240076)。
文摘Driven by the burgeoning demand for wearable electronics,the development of inherently safe,mechanically compliant,and high-energy–density power sources has become imperative.Flexible aqueous Zn ions batteries(FAZIBs)are hampered by Zn dendrite formation and hydrogen evolution,underscoring the urgent need for highly stable and novel flexible energy-storage devices.Although flexible aqueous cobalt-ion batteries(FACIBs)employing cobalt-salt aqueous electrolytes exhibit high theoretical capacity,they suffer from two limitations:the rapid dissolution of cathode active substances in the aqueous electrolyte and the risk of liquid electrolyte leakage under mechanical deformation.Here,we report the first realization of an ultra-stable,quasi-solid-state and mechanically FACIBs.Polyacrylamide(PAM)containing CoSO_(4) serves as the quasi-solid electrolyte,while cobalt hexacyanoferrate(CoHCF)functions as the cathode active material,and metallic cobalt foil as the flexible anode.This configuration simultaneously eliminates electrolyte leakage and suppresses the dissolution of CoHCF due to the common-ion effect of Co^(2+).Consequently,the fabricated FACIBs exhibit extraordinary cycling durability and remarkable mechanical robustness(95.9%retention after 500 bending cycles).Thus,this work provides a new way for designing ultra-stable energy storage devices for wearable electronics.
基金financial support from projects funded by the National Natural Science Foundation of China(52172038,22179017)the National Key Research and Development Program of China(2022YFB4101600,2022YFB4101601)。
文摘For rechargeable aqueous zinc-ion batteries(ZIBs),the design of nanocomposites comprised of electrochemically active materials and carbon materials with novel structures has great prom-ise in addressing the issue of electrical conductivity and structural stability in the electrode materials during electrochemical cycling.We report the production of a novel flexible electrode material,by anchoring MnO_(2) nanosheets on a B,N co-doped carbon nanotube ar-ray(BNCNTs)grown on carbon cloth(BNCNTs@MnO_(2)),which was fabricated by in-situ pyrolysis and hydrothermal growth.The generated BNCNTs were strongly bonded to the surface of the car-bon fibers in the carbon cloth which provides both excellent elec-tron transport and ion diffusion,and improves the stability and dur-ability of the cathode.Importantly,the BNCNTs offer more active sites for the hydrothermal growth of MnO_(2),ensuring a uniform dis-tribution.Electrochemical tests show that BNCNTs@MnO_(2) delivers a high specific capacity of 310.7 mAh g^(−1) at 0.1 A g^(−1),along with excellent rate capability and outstanding cycling stability,with a 79.7% capacity retention after 8000 cycles at 3 A g^(−1).
文摘Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in scalable flexible fabrication.In this study,a high-stability fluorescent ink was developed by incorporating QDs into a polydimethylsiloxane(PDMS)colloidal matrix.High-performance patterned films were then obtained via systematic optimization of screen-printing parameters,with film quality governed by substrate type(131μm PDMS),QD concentration(1.5 mg/mL),and screen mesh count(420 mesh).The optimized films exhibit outstanding environmental and photostability,retaining 75.6% of their fluorescence intensity after immersion in deionized water and 63.8% in 75%ethanol at 25℃ for 100 minutes.Under UV irradiation(365 nm,9 W,100 min),fluorescence intensity decreases by less than 20%.Utilizing their daylight transparency and UV-excitable luminescence,various patterns including QR codes and Code 93 standard barcodes were fabricated via screen printing with high pattern fidelity and machine readability.This study presents a scalable and reliable strategy for the fabrication of flexible,high-stability fluorescent films,supporting their integration into next-generation optoelectronic devices,advanced displays,and secure anti-counterfeiting.
文摘Flexible polymer electronics have emerged as an important research frontier in materials science due to their unique advantages,including mechanical flexibility,lightweight characteristics,and solution processability.These features enable a wide range of emerging applications such as wearable electronics,electronic skins,and biomedical devices,etc.In recent years,much advances in polymer chemistry,device physics,and interface engineering have significantly improved the performance of flexible polymer electronic devices,accelerating their transition from fundamental research to practical applications.
基金the National Natural Science Foundation of China(Grant No.32371823)the Liaoning Province Xingliao Talents Leading Talent Program(Grant No.XLYC2402043)the Open Foundation of State Key Laboratory of Woody Oil Resources Utilization(Grant No.SKLN EFU202517).
文摘Cellulose,the dominant natural polymer on Earth,features a distinct molecular structure with extraordinary mechanical properties and tunable characteristics,making it attractive for gel systems.Although significant progress has been made,challenges remain in fully leveraging their functional potential and broadening practical applications.This review systematically examines the properties of cellulose and cellulose gels,exploring novel reinforcement strategies—across molecular,supramolecular network,and macroscale structure levels—to enhance mechanical,electrical,and thermal performance,while coordinating these properties for practical implementations.These advancements are exemplified in emerging fields such as flexible robotics,electronic skins,flexible energy storage devices,and human-machine interaction systems.This article thoroughly investigates the fundamental characteristics,multi-scale design approaches,performance enhancement mechanisms,and cutting-edge implementations of cellulose-based gels across diverse domains.It provides a comprehensive overview of these advanced materials and offers strategic insights and recommendations for future research and innovation.
基金supported by the National Natural Science Foundation of China(Nos.22205105,61874053,22075136)National Key Basic Research Program of China(No.2020YFA0709900)Jiangsu Provincial Postgraduate Scientific Research Innovation Program(No.KYCX24_1649).
文摘Improving the optoelectronic behavior and stress-deformation stability of conjugated materials is crucial for the realization of their potential applications in flexible optoelectronics.To tune the emission behavior and mechanical property of molecular crystals simultaneously via supramolecular salt strategy is rarely reported,which is very important to improve their photophysical behavior and softness for the fabrication of flexible light-emitting device.Herein,supramolecular salt approach has been successfully applied to synthesize two elastic organic fluorescent crystals(CMOH-Py-Cl and CMOH-Py-Br)derived from non-emissive and brittle pyridine-substituted coumarin derivative(CMOH-Py).Their elastic properties can be attributed to the prevalent presence of numerous weak interactions introduced by halogen atoms,which are beneficial to the absorption and release of mechanical energy.Furthermore,density functional theory(DFT)calculations demonstrated a narrowing of the HOMO-LUMO energy gaps from CMOH-Py to CMOH-Py-Cl/CMOH-Py-Br via supramolecular salt approach.Finally,the application of flexible crystal materials in the field of optical waveguides has been investigated.The transformation of crystals in terms of photophysical and mechanical properties,achieved by the supramolecular salt approach,offers novel insights into the design and construction of flexible crystalline materials,providing a new path for the development of next-generation smart materials.
基金supported in part by the National Natural Science Foundation of China(62274033)Natural Science Foundation of Jiangsu Province(BK20221453)Fundamental Research Funds for the Central Universities.
文摘The increasing pursuit of ultra-high resolution displays has driven the demand for thin film transistors(TFTs)with higher mobility,especially on flexible substrates.In this work,we developed indium tin oxide(ITO)TFTs on flexible substrates for the first time and achieved a remarkable average mobility of 39.1 cm^(2)·V^(-1)·s^(-1),via mass-production compatible processes uti-lizing SiO_(2)gate dielectric.Benefiting from the ultra-flat surface and extremely low coefficient of thermal expansion(CTE)of our PI substrate,the ITO TFTs exhibit excellent large-scale uniformity.Additionally,the TFTs generate minor variations of-5.5%and+0.45 V in mobility and threshold voltage under a bending radius of 7 mm,respectively.They stay fully functional even after a dynamic bending test up to 13000 cycles,observing no obvious degradation in mobility and threshold voltage.The reliable mechanical flexibility and robust bending durability demonstrate their great potential for ultra-high resolution flexible displays in the future.
基金the financial support from the National University of Singapore(Grant No.A-001002800-00)the Singapore Ministry of Education(Grant No.A-8003587-00-00)。
文摘Health monitoring is becoming increasingly critical for disease prevention,early diagnosis,and highquality living.Polymeric materials,with their mechanical flexibility,biocompatibility,and tunable biochemical properties,offer unique advantages for creating next-generation personalized devices.In recent years,flexible polymer-based platforms have shown remarkable potential to capture diverse physiological signals in both daily and clinical contexts,including electrophysiological,biochemical,mechanical,and thermal indicators.In this review,we introduce a safety-leveloriented framework to evaluate material and device strategies for health monitoring,spanning the continuum from noninvasive wearables to deeply embedded implants.Physiological signals are systematically classified by use case,and application-specific requirements such as stability,comfort,and long-term compatibility are highlighted as critical factors guiding the selection of polymers,interfacial designs,and device architectures.Special emphasis is placed on mapping material types—including hydrogels,elastomers,and conductive composites—to their most suitable applications.Finally,we propose design principles for developing safe,functional,and adaptive polymer-based systems,aiming at reliable integration with the human body and enabling personalized,preventive healthcare.
基金supported by the National Natural Science Foundation of China(No.52403035)the Shanghai Sailing Program(23YF1400300)+1 种基金the Fundamental Research Funds for the Central Universities(2232023D-05)the Weiqiao Teaching and Research Innovation Program.
文摘The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness.
基金the financial support of the National Natural Science Foundation of China(NO.52173028)。
文摘Since the first design of tactile sensors was proposed by Harmon in 1982,tactile sensors have evolved through four key phases:industrial applications(1980s,basic pressure detection),miniaturization via MEMS(1990s),flexible electronics(2010s,stretchable materials),and intelligent systems(2020s-present,AI-driven multimodal sensing).With the innovation of material,processing techniques,and multimodal fusion of stimuli,the application of tactile sensors has been continuously expanding to a diversity of areas,including but not limited to medical care,aerospace,sports and intelligent robots.Currently,researchers are dedicated to develop tactile sensors with emerging mechanisms and structures,pursuing high-sensitivity,high-resolution,and multimodal characteristics and further constructing tactile systems which imitate and approach the performance of human organs.However,challenges in the combination between the theoretical research and the practical applications are still significant.There is a lack of comprehensive understanding in the state of the art of such knowledge transferring from academic work to technical products.Scaled-up production of laboratory materials faces fatal challenges like high costs,small scale,and inconsistent quality.Ambient factors,such as temperature,humidity,and electromagnetic interference,also impair signal reliability.Moreover,tactile sensors must operate across a wide pressure range(0.1 k Pa to several or even dozens of MPa)to meet diverse application needs.Meanwhile,the existing algorithms,data models and sensing systems commonly reveal insufficient precision as well as undesired robustness in data processing,and there is a realistic gap between the designed and the demanded system response speed.In this review,oriented by the design requirements of intelligent tactile sensing systems,we summarize the common sensing mechanisms,inspired structures,key performance,and optimizing strategies,followed by a brief overview of the recent advances in the perspectives of system integration and algorithm implementation,and the possible roadmap of future development of tactile sensors,providing a forward-looking as well as critical discussions in the future industrial applications of flexible tactile sensors.
基金supported by the Science and Technology Project of the State Grid Corporation of China“Research on Comprehensive Value Evaluation Method of Flexible Adjusting Resources under Carbon-electricity-certificate Market Coupling Environment”(No.5108-202455038A-1-1-ZN).
文摘The energy transition inspired by carbon neutrality targets and the increasing threat of extreme events raise multi-objective development requirements for power systems.This paper proposes a multi-objective resource allocation model to determine the type,number and location of flexible resources to increase the values of resilience,carbon reduction and renewable energy consumption.To evaluate the values of resilience,a restoration model for transmission systems is established that considers the coordination of fossil-fuel generators,energy storage systems(ESSs)and renewable energy generators in building restoration paths.The collaborative power-carbon-tradable green certificate(TGC)market model is then applied to evaluate the resource values in terms of carbon reduction and renewable energy consumption.Finally,the model is formulated as a mixed-integer linear programming(MILP)with a nonconvex feasible domain,and the normalized normal constraint(NNC)method is applied to obtain approximate Pareto frontiers for decision makers.Case studies validate the effectiveness of the proposed model in improving multi-factor values and analyze the impact of resource regulation capacity on values of restoration and carbon reduction.
基金supported by the NSFC(12474071)Natural Science Foundation of Shandong Province(ZR2024YQ051)+5 种基金Open Research Fund of State Key Laboratory of Materials for Integrated Circuits(SKLJC-K2024-12)the Shanghai Sailing Program(23YF1402200,23YF1402400)Natural Science Foundation of Jiangsu Province(BK20240424)Taishan Scholar Foundation of Shandong Province(tsqn202408006)Young Talent of Lifting engineering for Science and Technology in Shandong,China(SDAST2024QTB002)the Qilu Young Scholar Program of Shandong University.
文摘The advancement of flexible memristors has significantly promoted the development of wearable electronic for emerging neuromorphic computing applications.Inspired by in-memory computing architecture of human brain,flexible memristors exhibit great application potential in emulating artificial synapses for highefficiency and low power consumption neuromorphic computing.This paper provides comprehensive overview of flexible memristors from perspectives of development history,material system,device structure,mechanical deformation method,device performance analysis,stress simulation during deformation,and neuromorphic computing applications.The recent advances in flexible electronics are summarized,including single device,device array and integration.The challenges and future perspectives of flexible memristor for neuromorphic computing are discussed deeply,paving the way for constructing wearable smart electronics and applications in large-scale neuromorphic computing and high-order intelligent robotics.
基金supported by National Natural Science Foundation of China(Grant No.52272100)the Fund of Science and Technology on Advanced Ceramic Fibers and Composites Laboratory(Grant No.WDZC20215250507)the Fund of National Key Laboratory of Nuclear Reactor Technology of Nuclear Power Institute of China(KGSW-0324-0301-08)。
文摘The demand for sensors capable of operating in extreme environment of the fields,such as aerospace vehicles,aeroengines and fire protection,is rapidly increasing.However,developing flexible ceramic fibrous pressure sensors that combine high temperature stability with robust mechanical properties remains a significant challenge.Herein,through precise multi-scale process control,high-strength(2.1 MPa)TiC-SiC flexible fibrous membrane is successfully fabricated.The membrane exhibits exceptional thermal resistance(2000℃)and long–term thermal stability(1800℃ for 5 h)in the inert atmosphere.Meanwhile,the TiC-SiC fibrous membrane shows excellent oxidation resistance and still achieves strength of 1.8 MPa after being oxidized at 1200℃ for 1 h in air.Remarkably,TiC-SiC fibrous membrane withstands a load of approximately 1400 times its own weight and the ablation of butane flame(~1300℃)for at least 1 h without breaking.Notably,after heat treatment at 1800℃ for 5 h in an argon atmosphere,the TiC-SiC fibrous membrane even sustains pressure–sensing performance for up to 300 cycles.The membrane exhibits stable resistivity up to 900℃ and shows sensing stability under butane flame.The results of this work provide an effective and feasible solution to fill the research gap of flexible fibrous sensors for extreme environments.
基金supported by the National Natural Science Foundation of China(no.52574348)the Natural Science Foundation of Hebei Province(nos.E2024501010 and B2024501004)+3 种基金the Shijiazhuang Basic Research Project(no.241790667A)the Fundamental Research Funds for the Central Universities(no.N2423013)the National College Students Innovation and Entrepreneurship Training Program(no.202419145017)the Performance Subsidy Fund for Key Laboratory of Dielectric,Electrolyte Functional Material Hebei Province(no.22567627H)。
文摘MnO_(2) emerges as a promising cathode material for aqueous zinc-ion batteries(AZIBs)due to its high theoretical capacity and ideal working voltage.However,inherent limitations in low electrical conductivity and structural instability restrict its widespread application.Herein,we fabricated layered δ-MnO_(2) and introduced Cu and Ce metal ions for structural regulation,thus constructing a δ/a-MnO_(2) heterostructure within the δ-MnO_(2) matrix,forming a heterointerface that simultaneously enhances the electrical conductivity and structural stability of the material.In this system,Cu^(2+)acts as a catalyst,promoting the reduction of high-valent Mn to Mn^(2+)and enabling local two-electron transfer,which significantly increases the discharge specific capacity of MnO_(2).For Ce^(3+),it functions as a structural regulator,inducing the partial transformation of δ-MnO_(2) to a-MnO_(2) and forming the δ/a-MnO_(2) heterostructure.Further supported by density functional theory(DFT)calculations and in-situ characterization results,the heterointerface between a-MnO_(2) andδ-MnO_(2) generates an internal electric field due to the difference in Fermi levels.This not only effectively enhances the electron transfer capability but also significantly improves structural stability.Benefiting from these advantages,the Cu,Ce co-incorporated MnO_(2)(CCMO)cathode delivers a high discharge capacity of 455.4 mAh g^(-1)at 0.2 A g^(-1)and maintains 191.2 mAh g^(-1)specific capacity after 1500 cycles with 95%capacity retention at 2 A g^(-1),which is significantly better than non-doped MnO_(2).This strategy of structural regulation and heterostructure construction using vip ions offers a new approach for developing high-performance Mn-based cathode materials for AZIBs.
基金funded by the National Key Research and Development Program of China(2022YFB3807105)National Natural Science Foundation of China(52090033)+3 种基金State Key Laboratory for Modification of Chemical Fibers and Polymer Materials(KF222318)Jiangsu Province Industry-University-Research Cooperation Project(BY2022799)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX243534KYCX243521)。
文摘Photo-assisted flexible energy storage devices,combining photoelectric conversion and electrochemical energy storage,emerge as an innovative solution for sustainable energy systems.This review comprehensively summarizes recent advances in photo-assisted flexible energy storage technology,covering material design,working mechanisms,and practical applications.We systematically examine diverse electrode materials,such as metal oxides,metal sulfides,organic photosensitive materials,and composites,emphasizing their roles in boosting device performance.Special focus is placed on emerging technologies—including heterostructure engineering,surface modification,and intelligent control systems—that have notably enhanced energy conversion efficiency and storage capacity.The review also discusses current challenges,such as material stability,conversion efficiency,and standardization,and proposes strategic directions for future development.Recent breakthroughs in photo-assisted supercapacitors,lithium-based batteries,zinc-based batteries,and other innovative storage systems are critically assessed,offering key insights into their practical application potential in wearable electronics,self-powered sensors,and beyond.This comprehensive analysis establishes a framework for understanding the current status of photo-assisted flexible energy storage technology and guides future research toward high-performance,sustainable energy storage solutions.
文摘Conducting hydrogels have garnered significant interest in the field of wearable electronics.However,simultaneously achieving high transparency,high conductivity,strong adhesion,and self-healing ability within a short time remains a major challenge.In this study,a multifunctional mussel-inspired hydrogel was synthesized in only 5 min,with polydopamine(PDA)-polypyrrole(Ppy)-polyaniline(PANi)and poly(vinyl alcohol)(PVA)nanoparticles incorporated into the polyacrylamide(PAM)network.The resulting hydrogel exhibited high transparency(about 90% light transmission in the range of 400-800 nm),high conductivity((95.4±0.4)×10^(-4)S/cm),tensile strength(32.60±1.03 k Pa),strain at break(904.46%±11.50%),and adhesive strength(30-60 k Pa).It also demonstrated rapid self-healing properties(about 48% strength recovery within 1h at 50℃)and water-dependent shape memory behavior.As a wearable strain sensor,the hydrogel successfully detected finger flexion,wrist movements,facial expression changes,and breathing with high sensitivity and stability.The calculated gauge factor(GF)was 7.44±0.31,which is higher than that of many previously reported hydrogels.Compared with previous oyster-inspired or Ppy-based hydrogels,our system showed a much shorter synthesis time,higher transparency,and enhanced multifunctionality.These findings highlight the potential of the proposed hydrogel for next-generation flexible electronics,e-skin,and biomedical monitoring devices.
基金supported by the National Key Research and Development Program of China(Grant No.2024YFB4205300)the National Natural Science Foundation of China(Grant No.52173243)+2 种基金the Natural Science Foundation of Guangdong Province(Grant No.2021A1515011409)Shenzhen&Hong Kong Joint Research Program(Grant No.SGDX20201103095605015)SIAT-CUHK Joint Laboratory of Photovoltaic Solar Energy.
文摘This study presents a systematic investigation of high-efficiency flexible copper indium gallium selenide(CIGS)thin-film solar cells fabricated using an optimized three-stage co-evaporation process.The research focuses on two key innovations:(1)NaF pre-deposition for controlled alkali metal doping and(2)active regulation of In/Ga evaporation timing during the initial growth stage to precisely engineer the Ga/(Ga+In)(GGI)ratio gradient throughout the absorber layer depth.Through comprehensive characterization of structural properties,elemental distributions,and device performance,we demonstrate that the synergistic combination of Na doping and tailored Ga grading effectively addresses critical challenges in flexible CIGS devices,including back-surface Ga accumulation and non-ideal bandgap profiles.Our results reveal that this dual optimization strategy significantly enhances charge carrier mobility and collection efficiency,ultimately leading to substantial improvements in overall solar cell performance.The findings establish a robust materials engineering approach for developing high-performance flexible photovoltaic devices through precise control of compositional gradients and defect passivation.
基金financially supported by the National Key R&D Program of China(No.2023YFB3812400)the National Natural Science Foundation of China(No.51890871)the GJYC Program of Guangzhou(No.2024D02J0004)。
文摘The development of high-performance transparent substrates is critical for next-generation flexible electronic devices.Herein,we designed two novel meta-substituted diamines incorporating trifluoromethyl(―CF_(3))and methyl(―CH_(3))groups to synthesize colorless copolyimide(CPI)films via copolymerization with 4,4′-(hexafluoroisopropylidene)diphthalic anhydride(6FDA)/3,3′,4,4′-biphenyltetracarboxylic dianhydride(BPDA).The combination of meta-substituted architecture and substituents enables the simultaneous attainment of an ultralow dielectric constant(D_k)and high transparency.The meta-substitution geometry and electronic effects of―CF_(3)/―CH_(3) effectively suppressed charge-transfer complex(CTC)formation,expanded fractional free volume(FFV),and restricted π-electron conjugation,as validated by DFT calculations and wide-angle X-ray diffraction(WAXD)analysis.The optimized CPI film(PIA_(1)-6FDA/BPDA(10/0))achieved outstanding transmittance(T_(450)=88.15%),ultralow dielectric constant(D_(k)=2.08 at 1 k Hz),and minimal dielectric loss(D_(f)=0.0012),while maintaining robust thermal stability(T_(d5%)>523℃)and mechanical strength(σ=87.5 MPa).This work establishes a molecular engineering strategy to concurrently enhance the optical and dielectric properties,positioning meta-substituted CPIs as promising candidates for transparent flexible devices.
基金support from the National Key R&D Program of China(Grant No.2023YFB4005204)the National Natural Science Foundation of China(Grant No.22125903,U24A20553,22579025,52502038)+2 种基金Fundamental Research Funds for the Central Universities(No.2572023CT06)Key Joint Project of the Natural Science Foundation of Heilongjiang Province,China(No.ZL2024E007)the Innovation Foundation for Doctoral Program of Forestry Engineering of Northeast Forestry University(No.LYGC202220).
文摘The demand for sustainable energy storage has accelerated the development of cellulose-based materials(CBMs)for flexible supercapacitors(FSCs).However,widespread commercialization of FSCs remains challenged by their low gravimetric energy density(approximately 35 Wh kg^(-1)),far below lithium-ion batteries(exceeding 200 Wh kg^(-1)),and a limited operational temperature range(from-20℃ to 60℃),restricting their use in extreme environments.To date,no comprehensive review has elucidated the crucial role of the chemistry and structure-property relationships of CBMs in advancing FSC technology.This review fills this gap by examining the chemical attributes and versatility of cellulose and its derivatives,including their physicochemical characteris-tics,assembly methodologies,and functional modifications such as oxidation,esterification,etherification,grafting polymerization,nucleophilic substitution,and crosslinking reactions.We further provide an overview of the chemistry and structure-function correlations of various cellulose forms used in advanced electrodes,solid electrolytes,separators,binders,current collectors,and substrate/encapsulation materials,alongside relevant microelectrode processing technologies.Given that large-scale application of FSCs is still in its early stages,we offer insightful design principles for guiding future development of cellulose-based FSCs.By proposing a“chemistry-performance-sustainability”design framework,this review not only addresses existing limitations but also outlines a roadmap for next-generation eco-friendly FSCs.
基金financially supported by National Natural Science Foundation of China(52575458,52405424,52275575)Science and Technology Programme of Fujian Province(2024J010011,2024H0002)。
文摘Temperature stability is essential for the precision of flexible sensors.However,constrained by the composite principle of heterogeneous materials,the existing self-compensating methods encounter substantial challenges.To tackle this,high-entropy alloy nanofibers were utilized to construct a flexible strain sensor with inherent temperature stability.This approach leverages the electrohydrodynamic direct writing;a precursor conductive network was established through the electrospinning of a high-entropy alloy acetate and polyvinylidene difluoride solution blend.Subsequently,annealing treatment facilitated metallization,resulting in the synergistic preservation of polymer stretchability and the low temperature coefficient of resistance properties of high-entropy alloys inside the nanofibers.The test results demonstrate that the high-entropy alloys flexible strain sensor exhibits a remarkably low temperature coefficient of resistance(45.59 ppm K^(-1))across the range of-10 to 70℃,a sensitivity coefficient GF of 1.12 with a 50%strain range,and a response time of 310 ms.After 6000 stretching cycles,no baseline drift or failure occurred,indicating excellent cyclic stability.Furthermore,the outstanding temperature stability of the sensor was validated through wearable application and robotic hands strain sensing conducted under varied environment temperatures.This work provides a viable design pathway for developing flexible sensors with an inherently low temperature coefficient of resistance.
