The rapid advancement of modern electronics has led to a surge in solid electronic waste,which poses significant environmental and health challenges.This review focuses on recent developments in paper-based electronic...The rapid advancement of modern electronics has led to a surge in solid electronic waste,which poses significant environmental and health challenges.This review focuses on recent developments in paper-based electronic devices fabricated through low-cost,hand-printing techniques,with particular emphasis on their applications in energy harvesting,storage,and sensing.Unlike conventional plastic-based substrates,cellulose paper offers several advantages,including biodegradability,recyclability,and low fabrication cost.By integrating functional nanomaterials such as two-dimensional chalcogenides,metal oxides,conductive polymers,and carbon-based structures onto paper,researchers have achieved high-performance devices such as broadband photodetectors(responsivity up to 52 mA/W),supercapacitors(energy density~15.1 mWh/cm^(2)),and pressure sensors(sensitivity~18.42 kPa^(-1)).The hand-printing approach,which eliminates the need for sophisticated equipment and toxic solvents,offers a promising route for scalable,sustainable,and disposable electronics.This review outlines fabrication methods and key performance metrics,and discusses the current challenges and future directions for realizing robust,flexible devices aligned with green technology and the United Nation’s Sustainable Development Goals.展开更多
Flexible electronics and optoelectronics exhibit inevitable trends in next-generation intelligent industries,including healthcare and wellness,electronic skins,the automotive industry,and foldable or rollable displays...Flexible electronics and optoelectronics exhibit inevitable trends in next-generation intelligent industries,including healthcare and wellness,electronic skins,the automotive industry,and foldable or rollable displays.Traditional bulk-material-based flexible devices considerably rely on lattice-matched crystal structures and are usually plagued by unavoidable chemical disorders at the interface.Two-dimensional van der Waals materials(2D VdWMs)have exceptional multifunctional properties,including large specific area,dangling-bond-free interface,plane-to-plane van der Waals interactions,and excellent mechanical,electrical,and optical properties.Thus,2D VdWMs have considerable application potential in functional intelligent flexible devices.To utilize the unique properties of 2D VdWMs and their van der Waals heterostructures,new designs and configurations of electronics and optoelectronics have emerged.However,these new designs and configurations do not consider lattice mismatch and process incompatibility issues.In this review,we summarized the recently reported 2D VdWM-based flexible electronic and optoelectronic devices with various functions thoroughly.Moreover,we identified the challenges and opportunities for further applications of 2D VdWM-based flexible electronics and optoelectronics.展开更多
Flexible electronics technology is considered as a revolutionary technology to unlock the bottleneck of traditional rigid electronics that prevalent for decades,thereby fueling the next-generation electronics.In the p...Flexible electronics technology is considered as a revolutionary technology to unlock the bottleneck of traditional rigid electronics that prevalent for decades,thereby fueling the next-generation electronics.In the past few decades,the research on flexible electronic devices based on organic materials has witnessed rapid development and substantial achievements,and inorganic semiconductors are also now beginning to shine in the field of flexible electronics.As validated by the latest research,some of the inorganic semiconductors,particularly those at low dimension,unexpectedly exhibited excellent mechanical flexibility on top of superior electrical properties.Herein,we bring together a comprehensive analysis on the recently burgeoning low-dimension inorganic semiconductor materials in flexible electronics,including one-dimensional(1D)inorganic semiconductor nanowires(NWs)and two-dimensional(2D)transition metal dichalcogenides(TMDs).The fundamental electrical properties,optical properties,mechanical properties and strain engineering of materials,and their performance in flexible device applications are discussed in detail.We also propose current challenges and predict future development directions including material synthesis and device fabrication and integration.展开更多
The conventional analytical method of predicting strain in a thin film under bending is restricted to the uniform material assumption, while in flexible electronics, the film/substrate structure is widely used with mi...The conventional analytical method of predicting strain in a thin film under bending is restricted to the uniform material assumption, while in flexible electronics, the film/substrate structure is widely used with mismatched material properties taken into account. In this paper,a piecewise model is proposed to analyze the axial strain in a thin film of flexible electronics with the shear modification factor and principle of virtual work. The excellent agreement between analytical prediction and finite element results indicates that the model is capable of predicting the strain of the film/substrate structure in flexible electronics, whose mechanical stability and electrical performance is dependent on the strain state in the thin film.展开更多
Flexible electronics offer a multitude of advantages,such as flexibility,lightweight property,portability,and high durability.These unique properties allow for seamless applications to curved and soft surfaces,leading...Flexible electronics offer a multitude of advantages,such as flexibility,lightweight property,portability,and high durability.These unique properties allow for seamless applications to curved and soft surfaces,leading to extensive utilization across a wide range of fields in consumer electronics.These applications,for example,span integrated circuits,solar cells,batteries,wearable devices,bio-implants,soft robotics,and biomimetic applications.Recently,flexible electronic devices have been developed using a variety of materials such as organic,carbon-based,and inorganic semiconducting materials.Silicon(Si)owing to its mature fabrication process,excellent electrical,optical,thermal properties,and cost efficiency,remains a compelling material choice for flexible electronics.Consequently,the research on ultra-thin Si in the context of flexible electronics is studied rigorously nowadays.The thinning of Si is crucially important for flexible electronics as it reduces its bending stiffness and the resultant bending strain,thereby enhancing flexibility while preserving its exceptional properties.This review provides a comprehensive overview of the recent efforts in the fabrication techniques for forming ultra-thin Si using top-down and bottom-up approaches and explores their utilization in flexible electronics and their applications.展开更多
The burgeoning interest in flexible electronics necessitates the creation of patterning technology specifically tailored for flexible substrates and complex surface morphologies.Among a variety of patterning technique...The burgeoning interest in flexible electronics necessitates the creation of patterning technology specifically tailored for flexible substrates and complex surface morphologies.Among a variety of patterning techniques,transfer printing emerges as one of the most efficient,cost-effective,and scalable methods.It boasts the ability for high-throughput fabrication of 0–3D micro-and nano-structures on flexible substrates,working in tandem with traditional lithography methods.This review highlights the critical issue of transfer printing:the flawless transfer of devices during the pick-up and printing process.We encapsulate recent advancements in numerous transfer printing techniques,with a particular emphasis on strategies to control adhesion forces at the substrate/device/stamp interfaces.These strategies are employed to meet the requirements of competing fractures for successful pick-up and print processes.The mechanism,advantages,disadvantages,and typical applications of each transfer printing technique will be thoroughly discussed.The conclusion section provides design guidelines and probes potential directions for future advancements.展开更多
As a potential flexible substrate for flexible electronics, a polymer-sandwiched ultra-thin silicon platform is stud- ied. SU-8 photoresist coated on the silicon membrane improves its flexibility as shown by an ANSYS ...As a potential flexible substrate for flexible electronics, a polymer-sandwiched ultra-thin silicon platform is stud- ied. SU-8 photoresist coated on the silicon membrane improves its flexibility as shown by an ANSYS simulation. Using the plasma enhanced chemical vapor deposited Si02/Si3N4 composite film as an etching mask, a 4＂ silicon- （100） wafer is thinned to 26[tm without rupture in a 30wt.% KOH solution. The thinned wafer is coated on both sides with 20 pm of SU-8 photoresist and is cut into strips. Then the strips are bent by a caliper to measure its bending radius. A sector model of bending deformation is adopted to estimate the radius of curvature. The determined minimal bending radius of the polymer-sandwiched ultra-thin silicon layer is no more than 3.3mm. The fabrication process of this sandwich structure can be used as a post-fabrication process for high performance flexible electronics.展开更多
Laminated hard-soft integrated structures play a significant role in the fabrication and development of flexible electronics devices. Flexible electronics have advantageous characteristics such as soft and light-weigh...Laminated hard-soft integrated structures play a significant role in the fabrication and development of flexible electronics devices. Flexible electronics have advantageous characteristics such as soft and light-weight, can be folded,twisted, flipped inside-out, or be pasted onto other surfaces of arbitrary shapes. In this paper, an analytical model is presented to study the mechanics of laminated hard-soft structures in flexible electronics under a stickup state. Thirdorder polynomials are used to describe the displacement field,and the principle of virtual work is adopted to derive the governing equations and boundary conditions. The normal strain and the shear stress along the thickness direction in the bimaterial region are obtained analytically, which agree well with the results from finite element analysis. The analytical model can be used to analyze stickup state laminated structures, and can serve as a valuable reference for the failure prediction and optimal design of flexible electronics in the future.展开更多
This study employs theoretical analysis to explore the application prospects of flexible electronics technology in wearable devices. The research first reviews the development history and theoretical foundations of fl...This study employs theoretical analysis to explore the application prospects of flexible electronics technology in wearable devices. The research first reviews the development history and theoretical foundations of flexible electronics technology, including materials science, electronic engineering, and human-computer interaction theory. Through systematic analysis, the study evaluates the theoretical potential of flexible displays, flexible sensors, and flexible energy storage devices in wearable technology. The research finds that flexible electronics technology can significantly improve the comfort, functionality, and durability of wearable devices. Theoretical analysis indicates that flexible sensors have unique advantages in physiological monitoring and human-computer interaction, while flexible displays and batteries may revolutionize the form and usage patterns of wearable devices. However, the study also points out theoretical challenges faced by flexible electronics technology, such as material stability and feasibility of large-scale manufacturing. To address these challenges, the research proposes an interdisciplinary research framework, emphasizing the synergistic innovation of materials science, electronic engineering, and ergonomics. Finally, the study envisions the theoretical prospects of integrating flexible electronics with other emerging technologies, providing directions for future research.展开更多
Flexible electronics is an emerging technology,which breaks through the constraints of traditional rigid electronics,enabling electronic devices to adapt to various complex application scenarios.Meanwhile,a variety of...Flexible electronics is an emerging technology,which breaks through the constraints of traditional rigid electronics,enabling electronic devices to adapt to various complex application scenarios.Meanwhile,a variety of functions including sensing,actuation and energy harvesting,promote flexible electronics to be widely used in healthcare,robotics,Internet of Things,and so on.Micro/nanomanufacturing is the key technology to realize flexible electronics.Through micro/nanomanufacturing,various micro/nano-scale electronic components such as transistors and sensors can be precisely fabricated on flexible substrates,endowing flexible electronics with excellent performance.On the other hand,the development of flexible electronics also provides new challenges for micro/nanomanufacturing,due to the new flexible materials and device morphology.Currently,flexible electronics and micro/nanomanufacturing have attracted great at-tention from researchers around the world.Scientists explore new materials and techniques to further expand the applications of flexible electronics.On this basis,we have organized a special topic on“Flexible Electronics and Micro/Nanomanufacturing”in National Science Open(NSO)to discuss the development of flexible electronics.The topic focuses on key issues in the design and manufacturing of flexible electronics.We have invited nine scientists from different fields to present their latest research findings and prospective analyses of flexible electronics systematically.展开更多
The realization of natural and authentic facial expressions in humanoid robots poses a challenging and prominent research domain,encompassing interdisciplinary facets including mechanical design,sensing and actuation ...The realization of natural and authentic facial expressions in humanoid robots poses a challenging and prominent research domain,encompassing interdisciplinary facets including mechanical design,sensing and actuation control,psychology,cognitive science,flexible electronics,artificial intelligence(AI),etc.We have traced the recent developments of humanoid robot heads for facial expressions,discussed major challenges in embodied AI and flexible electronics for facial expression recognition and generation,and highlighted future trends in this field.Developing humanoid robot heads with natural and authentic facial expressions demands collaboration in interdisciplinary fields such as multi-modal sensing,emotional computing,and human-robot interactions(HRIs)to advance the emotional anthropomorphism of humanoid robots,bridging the gap between humanoid robots and human beings and enabling seamless HRIs.展开更多
The microfractals of leaf skeletons can be effective substrates for flexible electronics due to their high surface-to-volume ratio,transparency,breathability and flexibility.The challenge lies in replicating these fra...The microfractals of leaf skeletons can be effective substrates for flexible electronics due to their high surface-to-volume ratio,transparency,breathability and flexibility.The challenge lies in replicating these fractal surfaces at the microscale in a way that is scalable,freestanding,and integrable with various materials.In this study,we present a novel method for the biomimetic microfabrication of leafskeleton-based fractal surfaces.We utilized a modified electrospinning method,replacing the fiber collector with a metalized biotic collector to replicate the microstructures.The biomimetic microfractals demonstrated~90%replication accuracy,>80%transparency,good stretchability,and breathability,and were freestanding.The method is versatile,allowing for the use of a wide range of polymers in biomimetic microfabrication.For application in flexible electronics,biomimetic conductive fractal patterns(BCFP)were fabricated by immobilizing Ag Nanowires(AgNW)using a simple spraybased method.The BCFP exhibited high conductivity with sheet resistances<20Ωsq-1 while maintaining good transparencies.The BCFP adheres conformally to human skin,acting as an electronic skin(e-skin).To demonstrate the application,the BCFP was used to fabricate a tactile pressure sensor.In addition to their excellent transparency at low sheet resistances,stretchability,moisture resistance,and tight conformal bonding with the target surface,the BCFP also allows the evaporation of perspiration,making them suitable for long-term use as epidermal sensors.The application of BCFP in advanced bionic skin was demonstrated through gesture monitoring experiments.展开更多
Ionogels,with their combined properties of flexibility,excellent ionic conductivity,and biomechanical characteristics similar to biological tissues,have become key materials in flexible electronics,exhibiting enormous...Ionogels,with their combined properties of flexibility,excellent ionic conductivity,and biomechanical characteristics similar to biological tissues,have become key materials in flexible electronics,exhibiting enormous appli-cation potential in fields such as health monitoring and smart wearables.However,ionogels are susceptible to mechanical damage.Under large deformations and continuous mechan-ical loading,structural damage and device failure are in-evitable.Self-healing ability can significantly improve the reliability,service life,and safety of devices.This review dis-cusses the latest progress in self-healing ionogels,covering self-healing mechanisms,as well as the design,preparation,and applications of various ionogel-based flexible electronic devices,including wearable sensors,flexible triboelectric na-nogenerators,supercapacitors,flexible displays,and soft ro-bots.Furthermore,based on the self-healing mechanisms of ionogels and the design and manufacturing of related pro-ducts,we put forward perspectives on the development of flexible electronics.This review is expected to accelerate the development of self-healing ionogels in the applications of various flexible electronic devices.展开更多
The rapid expansion of the Internet of Things(IoT)and wearable technologies has driven the demand for flexible,lightweight,and multifunctional electronic devices.However,conventional rigid electronics often fall short...The rapid expansion of the Internet of Things(IoT)and wearable technologies has driven the demand for flexible,lightweight,and multifunctional electronic devices.However,conventional rigid electronics often fall short in meeting the requirements for conformability,comfort,and durability in applications such as health monitoring,soft robotics,and human-machine interfaces(HMIs)[1].While two-dimensional materials like graphene and transition metal dichalcogenides have been extensively explored,their limitations in electrical conductivity,tunable surface properties,and scalable synthesis have spurred the search for alternative materials[2].展开更多
Self-rectifying memristor(SRM)arrays hold tremendous potential in high-density data storage and energy efficient neuromorphic computing.However,SRM arrays are mostly developed on rigid substrates and lack mechanical f...Self-rectifying memristor(SRM)arrays hold tremendous potential in high-density data storage and energy efficient neuromorphic computing.However,SRM arrays are mostly developed on rigid substrates and lack mechanical flexibility,limiting their applications in intelligent electronic skin,wearable technologies,etc.Here,we present a high performance SRM array based on Pt/HfO_(2)/Ta_(2)O_(5−x)/Ti heterojunctions,which can be fabricated on a flexible polyimides(PI)substrate and demonstrates exceptional memristive performance under bending conditions(bending radius(R)=1 cm,rectifying ratio>10^(4),retention time>10^(4) s and endurance>105 cycles).We demonstrate a 16×16 flexible memristor array offering noise filtering and data storage capabilities,which can be used to accurately process and store the signals transmitted by a pressure sensor array.This research represents an important advancement towards the realization of next-generation high-performance flexible electronics.展开更多
Flexible electronics have emerged as a revolutionary paradigm to unlock novel possibilities across diverse fields such as wearables,healthcare,and wireless communications.Among the numerous materials,liquid metal(LM)t...Flexible electronics have emerged as a revolutionary paradigm to unlock novel possibilities across diverse fields such as wearables,healthcare,and wireless communications.Among the numerous materials,liquid metal(LM)thin films,characterized by high electrical conductivity,high thermal conductivity,high ductility,and biocompatibility,have become crucial materials for the fabrication of flexible electronics.Nevertheless,the current state-of-the-art technologies still face several challenges including complex preparation processes,poor compatibility with substrates,and insufficient mechanical stability.In this comprehensive review,the innovative preparation technologies for LM thin films including patterned printing methods,various coatings techniques,and interface-driven assembly approaches have been systematically summarized.The underlying design principle which involves modulating the ratio of composition materials and process conditions,are elucidated in detail.Moreover,their innovative applications in flexible electronics are concluded.Finally,we provide a forward-looking perspective on the future research and development trends in this burgeoning field.It aims to guide and inspire further scientific investigations and technological advancements.展开更多
Organic field‐effect transistors are widely recognized as key enabling components for low‐cost,lightweight,and flexible electronic systems.Despite substantial research progress,a critical barrier to their commercial...Organic field‐effect transistors are widely recognized as key enabling components for low‐cost,lightweight,and flexible electronic systems.Despite substantial research progress,a critical barrier to their commercialization remains the fragmented understanding between materials chemistry,device physics,and manufacturing.In contrast to reviews that focus on isolated aspects,this research provides a distinctive integrative perspective,deliberately linking fundamental material properties with device‐level performance and operational stability.This approach is essential for addressing persistent issues such as environmental instability,significant contact resistance,and performance nonuniformity.We highlight recent progress in both p‐type and n‐type semiconductors,novel device architectures,and the underlying mechanisms of contact resistance.Particular emphasis is placed on interface engineering and structural optimization to mitigate parasitic losses and enhance operational stability.By bridging molecular design with contact engineering,this review outlines clear pathways toward reliable,high‐performance OFET for nextgeneration flexible electronics.展开更多
Flexible energy storage and harvesting devices,as core components of the flexible electronic system,have driven the transformation of electronic system from“external power supply”to“self-powering”and from“fixed f...Flexible energy storage and harvesting devices,as core components of the flexible electronic system,have driven the transformation of electronic system from“external power supply”to“self-powering”and from“fixed forms”to“adaptive configurations”,thus playing an important role in the advancement of wearable technology,the internet of things,and other related fields.MXenes,a class of two-dimensional transition metal carbides,nitrides,and carbonitrides,emerge as promising candidates for flexible energy storage and harvesting devices,attributed to their excellent conductivity,mechanical flexibility,and tunable interfacial characteristics.Specifically,the interfacial characteristics of MXenes,including surface energy,surface terminations,and interlayer spacing,have a decisive influence on the performance of MXene-based energy devices.This review summarizes the influence of microcosmic interfacial characteristics on macroscopic properties,the interfacial regulation strategies,and applications in flexible energy storage and harvesting of MXenes,concluding with current challenges and perspectives to guide the design of high-performance MXene-based energy devices.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
Reed membrane,a natural cellulosic material traditionally used in musical instruments,holds promise in flexible electronics due to its abundance,low cost,and excellent biocompatibility.However,its native form contains...Reed membrane,a natural cellulosic material traditionally used in musical instruments,holds promise in flexible electronics due to its abundance,low cost,and excellent biocompatibility.However,its native form contains water-soluble ions and lipid-soluble waxes that hinder performance in acoustic and electronics by compromising electrical insulation and mechanical stability.Here,supercritical fluid superposition purification(SCSP-WA)is introduced,which utilizes supercritical CO_(2)with water and acetone as bipolar co-solvents to selectively remove these impurities.Post-SCSP-WA treatment,the reed membrane exhibits significant enhancements in mechanical strength and electrical insulation,achieving a 4-fold increase in elongation at break,improved tensile strength and Young’s modulus,and a 98.5%reduction in leakage current,all while maintaining low and stable capacitance.These improvements stem from the restructuring of the fibrous network into a porous,interconnected microstructure.Material characterization(X-ray photoelectron spectroscopy(XPS),Fourier-transform infrared spectroscopy(FTIR),and scanning electron microscopy(SEM))confirmed the effective removal of magnesium and waxy functional groups,along with enhanced fiber crosslinking.Cytotoxicity tests further validated the biocompatibility of the SCSP-WA-treated membranes.This environmentally sustainable approach expands the potential of reed membranes in flexible bioelectronics and bio-integrated acoustic systems.展开更多
基金The Consortium for Scientific Research,Indore(CSR,Indore)(No.CRS/2021-22/01/426)is acknowledged by the authorsFor the research facilities,the authors are grateful to CHARUSAT University.
文摘The rapid advancement of modern electronics has led to a surge in solid electronic waste,which poses significant environmental and health challenges.This review focuses on recent developments in paper-based electronic devices fabricated through low-cost,hand-printing techniques,with particular emphasis on their applications in energy harvesting,storage,and sensing.Unlike conventional plastic-based substrates,cellulose paper offers several advantages,including biodegradability,recyclability,and low fabrication cost.By integrating functional nanomaterials such as two-dimensional chalcogenides,metal oxides,conductive polymers,and carbon-based structures onto paper,researchers have achieved high-performance devices such as broadband photodetectors(responsivity up to 52 mA/W),supercapacitors(energy density~15.1 mWh/cm^(2)),and pressure sensors(sensitivity~18.42 kPa^(-1)).The hand-printing approach,which eliminates the need for sophisticated equipment and toxic solvents,offers a promising route for scalable,sustainable,and disposable electronics.This review outlines fabrication methods and key performance metrics,and discusses the current challenges and future directions for realizing robust,flexible devices aligned with green technology and the United Nation’s Sustainable Development Goals.
基金supported by the Natural Science Foundation of Beijing Municipality(No.Z180011)the National Natural Science Foundation of China(Nos.51991340,51991342,51972022,92163205,and 52188101)+2 种基金the National Key Research and Development Program of China(No.2016YFA0202701)the Fundamental Research Funds for the Central Universities(No.FRF-TP-19-025A3)the Overseas Expertise Introduction Projects for Discipline Innovation(No.B14003)。
文摘Flexible electronics and optoelectronics exhibit inevitable trends in next-generation intelligent industries,including healthcare and wellness,electronic skins,the automotive industry,and foldable or rollable displays.Traditional bulk-material-based flexible devices considerably rely on lattice-matched crystal structures and are usually plagued by unavoidable chemical disorders at the interface.Two-dimensional van der Waals materials(2D VdWMs)have exceptional multifunctional properties,including large specific area,dangling-bond-free interface,plane-to-plane van der Waals interactions,and excellent mechanical,electrical,and optical properties.Thus,2D VdWMs have considerable application potential in functional intelligent flexible devices.To utilize the unique properties of 2D VdWMs and their van der Waals heterostructures,new designs and configurations of electronics and optoelectronics have emerged.However,these new designs and configurations do not consider lattice mismatch and process incompatibility issues.In this review,we summarized the recently reported 2D VdWM-based flexible electronic and optoelectronic devices with various functions thoroughly.Moreover,we identified the challenges and opportunities for further applications of 2D VdWM-based flexible electronics and optoelectronics.
基金supported by the Natural Science Foundation of China(No.51902101)Natural Science Foundation of Jiangsu Province(No.BK20201381)+1 种基金Science Foundation of Nanjing University of Posts and Telecommunications(No.NY219144)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.SJCX22_0254).
文摘Flexible electronics technology is considered as a revolutionary technology to unlock the bottleneck of traditional rigid electronics that prevalent for decades,thereby fueling the next-generation electronics.In the past few decades,the research on flexible electronic devices based on organic materials has witnessed rapid development and substantial achievements,and inorganic semiconductors are also now beginning to shine in the field of flexible electronics.As validated by the latest research,some of the inorganic semiconductors,particularly those at low dimension,unexpectedly exhibited excellent mechanical flexibility on top of superior electrical properties.Herein,we bring together a comprehensive analysis on the recently burgeoning low-dimension inorganic semiconductor materials in flexible electronics,including one-dimensional(1D)inorganic semiconductor nanowires(NWs)and two-dimensional(2D)transition metal dichalcogenides(TMDs).The fundamental electrical properties,optical properties,mechanical properties and strain engineering of materials,and their performance in flexible device applications are discussed in detail.We also propose current challenges and predict future development directions including material synthesis and device fabrication and integration.
基金support from the National Natural Science Foundation of China(No.11172022)the support by the China Postdoctoral Science Foundation(No.2013M530907)the National Natural Science Foundation of China(No.11302039)
文摘The conventional analytical method of predicting strain in a thin film under bending is restricted to the uniform material assumption, while in flexible electronics, the film/substrate structure is widely used with mismatched material properties taken into account. In this paper,a piecewise model is proposed to analyze the axial strain in a thin film of flexible electronics with the shear modification factor and principle of virtual work. The excellent agreement between analytical prediction and finite element results indicates that the model is capable of predicting the strain of the film/substrate structure in flexible electronics, whose mechanical stability and electrical performance is dependent on the strain state in the thin film.
基金supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. RS-2024-00353768)the Yonsei Fellowship, funded by Lee Youn Jae. This study was funded by the KIST Institutional Program Project No. 2E31603-22-140 (K J Y). S M W acknowledges the support by National Research Foundation of Korea (NRF) grant funded by the Korea government (Grant Nos. NRF-2021R1C1C1009410, NRF2022R1A4A3032913 and RS-2024-00411904)
文摘Flexible electronics offer a multitude of advantages,such as flexibility,lightweight property,portability,and high durability.These unique properties allow for seamless applications to curved and soft surfaces,leading to extensive utilization across a wide range of fields in consumer electronics.These applications,for example,span integrated circuits,solar cells,batteries,wearable devices,bio-implants,soft robotics,and biomimetic applications.Recently,flexible electronic devices have been developed using a variety of materials such as organic,carbon-based,and inorganic semiconducting materials.Silicon(Si)owing to its mature fabrication process,excellent electrical,optical,thermal properties,and cost efficiency,remains a compelling material choice for flexible electronics.Consequently,the research on ultra-thin Si in the context of flexible electronics is studied rigorously nowadays.The thinning of Si is crucially important for flexible electronics as it reduces its bending stiffness and the resultant bending strain,thereby enhancing flexibility while preserving its exceptional properties.This review provides a comprehensive overview of the recent efforts in the fabrication techniques for forming ultra-thin Si using top-down and bottom-up approaches and explores their utilization in flexible electronics and their applications.
基金financial support from the RGC Senior Research Fellowship Scheme(SRFS2122-5S04)General Research Fund(15304322)+1 种基金RGC Postdoctoral Fellowship(PDFS2324-5S10)State Key Laboratory for Ultraprecision Machining Technology(1-BBXR).
文摘The burgeoning interest in flexible electronics necessitates the creation of patterning technology specifically tailored for flexible substrates and complex surface morphologies.Among a variety of patterning techniques,transfer printing emerges as one of the most efficient,cost-effective,and scalable methods.It boasts the ability for high-throughput fabrication of 0–3D micro-and nano-structures on flexible substrates,working in tandem with traditional lithography methods.This review highlights the critical issue of transfer printing:the flawless transfer of devices during the pick-up and printing process.We encapsulate recent advancements in numerous transfer printing techniques,with a particular emphasis on strategies to control adhesion forces at the substrate/device/stamp interfaces.These strategies are employed to meet the requirements of competing fractures for successful pick-up and print processes.The mechanism,advantages,disadvantages,and typical applications of each transfer printing technique will be thoroughly discussed.The conclusion section provides design guidelines and probes potential directions for future advancements.
基金Supported by the State Scholarship Fund of Chinathe Open Research Fund of Shanghai Key Laboratory of Multidimensional Information Processing of East China Normal University
文摘As a potential flexible substrate for flexible electronics, a polymer-sandwiched ultra-thin silicon platform is stud- ied. SU-8 photoresist coated on the silicon membrane improves its flexibility as shown by an ANSYS simulation. Using the plasma enhanced chemical vapor deposited Si02/Si3N4 composite film as an etching mask, a 4＂ silicon- （100） wafer is thinned to 26[tm without rupture in a 30wt.% KOH solution. The thinned wafer is coated on both sides with 20 pm of SU-8 photoresist and is cut into strips. Then the strips are bent by a caliper to measure its bending radius. A sector model of bending deformation is adopted to estimate the radius of curvature. The determined minimal bending radius of the polymer-sandwiched ultra-thin silicon layer is no more than 3.3mm. The fabrication process of this sandwich structure can be used as a post-fabrication process for high performance flexible electronics.
基金supported by the National Natural Science Foundation of China (Grants 11572022 and 11172022)
文摘Laminated hard-soft integrated structures play a significant role in the fabrication and development of flexible electronics devices. Flexible electronics have advantageous characteristics such as soft and light-weight, can be folded,twisted, flipped inside-out, or be pasted onto other surfaces of arbitrary shapes. In this paper, an analytical model is presented to study the mechanics of laminated hard-soft structures in flexible electronics under a stickup state. Thirdorder polynomials are used to describe the displacement field,and the principle of virtual work is adopted to derive the governing equations and boundary conditions. The normal strain and the shear stress along the thickness direction in the bimaterial region are obtained analytically, which agree well with the results from finite element analysis. The analytical model can be used to analyze stickup state laminated structures, and can serve as a valuable reference for the failure prediction and optimal design of flexible electronics in the future.
文摘This study employs theoretical analysis to explore the application prospects of flexible electronics technology in wearable devices. The research first reviews the development history and theoretical foundations of flexible electronics technology, including materials science, electronic engineering, and human-computer interaction theory. Through systematic analysis, the study evaluates the theoretical potential of flexible displays, flexible sensors, and flexible energy storage devices in wearable technology. The research finds that flexible electronics technology can significantly improve the comfort, functionality, and durability of wearable devices. Theoretical analysis indicates that flexible sensors have unique advantages in physiological monitoring and human-computer interaction, while flexible displays and batteries may revolutionize the form and usage patterns of wearable devices. However, the study also points out theoretical challenges faced by flexible electronics technology, such as material stability and feasibility of large-scale manufacturing. To address these challenges, the research proposes an interdisciplinary research framework, emphasizing the synergistic innovation of materials science, electronic engineering, and ergonomics. Finally, the study envisions the theoretical prospects of integrating flexible electronics with other emerging technologies, providing directions for future research.
文摘Flexible electronics is an emerging technology,which breaks through the constraints of traditional rigid electronics,enabling electronic devices to adapt to various complex application scenarios.Meanwhile,a variety of functions including sensing,actuation and energy harvesting,promote flexible electronics to be widely used in healthcare,robotics,Internet of Things,and so on.Micro/nanomanufacturing is the key technology to realize flexible electronics.Through micro/nanomanufacturing,various micro/nano-scale electronic components such as transistors and sensors can be precisely fabricated on flexible substrates,endowing flexible electronics with excellent performance.On the other hand,the development of flexible electronics also provides new challenges for micro/nanomanufacturing,due to the new flexible materials and device morphology.Currently,flexible electronics and micro/nanomanufacturing have attracted great at-tention from researchers around the world.Scientists explore new materials and techniques to further expand the applications of flexible electronics.On this basis,we have organized a special topic on“Flexible Electronics and Micro/Nanomanufacturing”in National Science Open(NSO)to discuss the development of flexible electronics.The topic focuses on key issues in the design and manufacturing of flexible electronics.We have invited nine scientists from different fields to present their latest research findings and prospective analyses of flexible electronics systematically.
基金supported by the National Natural Science Foundation of China(nos.52188102 and 51925503)the Science and Technology Development Fund of Macao SAR(file na.0117/2024/AMJ)+1 种基金Zhuhai UM Science&Technology Research Institute(CP-009-2024)the State Key Laboratory of Intelligent Manufacturing Equipment and Tech-nology(IMETKF2024003),HUST,Wuhan,China.
文摘The realization of natural and authentic facial expressions in humanoid robots poses a challenging and prominent research domain,encompassing interdisciplinary facets including mechanical design,sensing and actuation control,psychology,cognitive science,flexible electronics,artificial intelligence(AI),etc.We have traced the recent developments of humanoid robot heads for facial expressions,discussed major challenges in embodied AI and flexible electronics for facial expression recognition and generation,and highlighted future trends in this field.Developing humanoid robot heads with natural and authentic facial expressions demands collaboration in interdisciplinary fields such as multi-modal sensing,emotional computing,and human-robot interactions(HRIs)to advance the emotional anthropomorphism of humanoid robots,bridging the gap between humanoid robots and human beings and enabling seamless HRIs.
基金supported by financial support from KONE Foundation,the Research Council of Finland(grant no.331368)project DURATRANS(364364,2024–2027,under the framework of M-ERA.Net)+2 种基金the Materials Research Infrastructure(MARI)at the University of Turku for infrastructural facilitiessupport by the UK Engineering and Physical Sciences Research Council(EPSRC)(grant no.:EP/Y011457/1)by the RAEng/Leverhulme Trust Research Fellowship(grant no.:LTRF-2324-20-129)。
文摘The microfractals of leaf skeletons can be effective substrates for flexible electronics due to their high surface-to-volume ratio,transparency,breathability and flexibility.The challenge lies in replicating these fractal surfaces at the microscale in a way that is scalable,freestanding,and integrable with various materials.In this study,we present a novel method for the biomimetic microfabrication of leafskeleton-based fractal surfaces.We utilized a modified electrospinning method,replacing the fiber collector with a metalized biotic collector to replicate the microstructures.The biomimetic microfractals demonstrated~90%replication accuracy,>80%transparency,good stretchability,and breathability,and were freestanding.The method is versatile,allowing for the use of a wide range of polymers in biomimetic microfabrication.For application in flexible electronics,biomimetic conductive fractal patterns(BCFP)were fabricated by immobilizing Ag Nanowires(AgNW)using a simple spraybased method.The BCFP exhibited high conductivity with sheet resistances<20Ωsq-1 while maintaining good transparencies.The BCFP adheres conformally to human skin,acting as an electronic skin(e-skin).To demonstrate the application,the BCFP was used to fabricate a tactile pressure sensor.In addition to their excellent transparency at low sheet resistances,stretchability,moisture resistance,and tight conformal bonding with the target surface,the BCFP also allows the evaporation of perspiration,making them suitable for long-term use as epidermal sensors.The application of BCFP in advanced bionic skin was demonstrated through gesture monitoring experiments.
基金supported by the National Natural Science Foundation of China(52573131,22203015)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZZ127)+2 种基金National Key Research and Development Program of China(2020YFA0710303)Fujian Provincial Natural Science Foundation of China(2024J01626)Fujian Provincial Health Technology Project(2024QNA016)。
文摘Ionogels,with their combined properties of flexibility,excellent ionic conductivity,and biomechanical characteristics similar to biological tissues,have become key materials in flexible electronics,exhibiting enormous appli-cation potential in fields such as health monitoring and smart wearables.However,ionogels are susceptible to mechanical damage.Under large deformations and continuous mechan-ical loading,structural damage and device failure are in-evitable.Self-healing ability can significantly improve the reliability,service life,and safety of devices.This review dis-cusses the latest progress in self-healing ionogels,covering self-healing mechanisms,as well as the design,preparation,and applications of various ionogel-based flexible electronic devices,including wearable sensors,flexible triboelectric na-nogenerators,supercapacitors,flexible displays,and soft ro-bots.Furthermore,based on the self-healing mechanisms of ionogels and the design and manufacturing of related pro-ducts,we put forward perspectives on the development of flexible electronics.This review is expected to accelerate the development of self-healing ionogels in the applications of various flexible electronic devices.
基金financially supported by the Department of Science and Technology of Guangdong Province (2023QN10L141)the Innovation and Entrepreneurship Team of Guangdong Provincial Pearl River Talents Program (2019ZT08L101)+1 种基金the Program for Shenzhen Science and Technology Innovation Committee (JSGGKQTD20221101115701006)the Guangdong Basic Research Center of Excellence for Aggregate Science。
文摘The rapid expansion of the Internet of Things(IoT)and wearable technologies has driven the demand for flexible,lightweight,and multifunctional electronic devices.However,conventional rigid electronics often fall short in meeting the requirements for conformability,comfort,and durability in applications such as health monitoring,soft robotics,and human-machine interfaces(HMIs)[1].While two-dimensional materials like graphene and transition metal dichalcogenides have been extensively explored,their limitations in electrical conductivity,tunable surface properties,and scalable synthesis have spurred the search for alternative materials[2].
基金This work was supported by the financial support from the National Key Research and Development Program of China(Nos.2021YFA1202600 and 2023YFF0719600)the National Natural Science Foundation of China(Nos.U23A20322,92164108,62174164 and U22A2075)+3 种基金Natural Science Foundation of Zhejiang Province(No.LR23E020001)Hunan Provincial Natural Science Foundation(Nos.2023JJ50009 and 2023JJ30599)Talent Plan of Shanghai Branch,Chinese Academy of Sciences(No.CASSHB-QNPD-2023-022)Ningbo Technology Project(No.2022A-007-C).
文摘Self-rectifying memristor(SRM)arrays hold tremendous potential in high-density data storage and energy efficient neuromorphic computing.However,SRM arrays are mostly developed on rigid substrates and lack mechanical flexibility,limiting their applications in intelligent electronic skin,wearable technologies,etc.Here,we present a high performance SRM array based on Pt/HfO_(2)/Ta_(2)O_(5−x)/Ti heterojunctions,which can be fabricated on a flexible polyimides(PI)substrate and demonstrates exceptional memristive performance under bending conditions(bending radius(R)=1 cm,rectifying ratio>10^(4),retention time>10^(4) s and endurance>105 cycles).We demonstrate a 16×16 flexible memristor array offering noise filtering and data storage capabilities,which can be used to accurately process and store the signals transmitted by a pressure sensor array.This research represents an important advancement towards the realization of next-generation high-performance flexible electronics.
基金supported by the National Natural Science Foundation of China(Nos.62174086,62474096,and 62288102)Basic Research Program of Jiangsu(No.BK20243057)+2 种基金Outstanding Youth Foundation of Jiangsu Province(No.BK20240139)Qinglan Project of Jiangsu Province of ChinaNational Entrepreneurship Training Program for College Students(No.202510293240E).
文摘Flexible electronics have emerged as a revolutionary paradigm to unlock novel possibilities across diverse fields such as wearables,healthcare,and wireless communications.Among the numerous materials,liquid metal(LM)thin films,characterized by high electrical conductivity,high thermal conductivity,high ductility,and biocompatibility,have become crucial materials for the fabrication of flexible electronics.Nevertheless,the current state-of-the-art technologies still face several challenges including complex preparation processes,poor compatibility with substrates,and insufficient mechanical stability.In this comprehensive review,the innovative preparation technologies for LM thin films including patterned printing methods,various coatings techniques,and interface-driven assembly approaches have been systematically summarized.The underlying design principle which involves modulating the ratio of composition materials and process conditions,are elucidated in detail.Moreover,their innovative applications in flexible electronics are concluded.Finally,we provide a forward-looking perspective on the future research and development trends in this burgeoning field.It aims to guide and inspire further scientific investigations and technological advancements.
基金Research Projects of Department of Education of Guangdong Province,Grant/Award Numbers:2024ZDZX3079,2023GCZX015Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2023A1515011677+5 种基金Innovation Team Project of Guangdong,Grant/Award Number:2022KCXTD055University‐Enterprise Joint Research and Development Center‐Advanced Carbon Materials R&D Center,Grant/Award Number:602431010PQNational Key Research and Development Program of China,Grant/Award Number:2023YFF0719600Ningbo Science and Technology Project,Grant/Award Numbers:2022A‐230‐G,2024Z242,2022‐DST‐004Natural Science Foundation of Ningbo,Grant/Award Number:2022J149Shenzhen Polytechnic University Postdoctoral Fund,Grant/Award Number:6025331012K。
文摘Organic field‐effect transistors are widely recognized as key enabling components for low‐cost,lightweight,and flexible electronic systems.Despite substantial research progress,a critical barrier to their commercialization remains the fragmented understanding between materials chemistry,device physics,and manufacturing.In contrast to reviews that focus on isolated aspects,this research provides a distinctive integrative perspective,deliberately linking fundamental material properties with device‐level performance and operational stability.This approach is essential for addressing persistent issues such as environmental instability,significant contact resistance,and performance nonuniformity.We highlight recent progress in both p‐type and n‐type semiconductors,novel device architectures,and the underlying mechanisms of contact resistance.Particular emphasis is placed on interface engineering and structural optimization to mitigate parasitic losses and enhance operational stability.By bridging molecular design with contact engineering,this review outlines clear pathways toward reliable,high‐performance OFET for nextgeneration flexible electronics.
基金supported by the National Natural Science Foundation of China(52422205,52403154)the National Key Research and Development Program of China(2023YFB3811303)+2 种基金the Natural Science Foundation of Sichuan Province(2026NSFSCZY0103,2026NSFSC1406)the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(GZC20230383)the China Postdoctoral Science Foundation(2025M770159)。
文摘Flexible energy storage and harvesting devices,as core components of the flexible electronic system,have driven the transformation of electronic system from“external power supply”to“self-powering”and from“fixed forms”to“adaptive configurations”,thus playing an important role in the advancement of wearable technology,the internet of things,and other related fields.MXenes,a class of two-dimensional transition metal carbides,nitrides,and carbonitrides,emerge as promising candidates for flexible energy storage and harvesting devices,attributed to their excellent conductivity,mechanical flexibility,and tunable interfacial characteristics.Specifically,the interfacial characteristics of MXenes,including surface energy,surface terminations,and interlayer spacing,have a decisive influence on the performance of MXene-based energy devices.This review summarizes the influence of microcosmic interfacial characteristics on macroscopic properties,the interfacial regulation strategies,and applications in flexible energy storage and harvesting of MXenes,concluding with current challenges and perspectives to guide the design of high-performance MXene-based energy devices.
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supported by the Shenzhen Scientific and Technological Foundation(RCYX20231211090332037 and JCYJ20240813160211015)the National Natural Science Foundation of China(62474008 and 62204007)+2 种基金the Guangdong Provincial Natural Science Foundation(2024A1515030044)the Guangdong Provincial Key Laboratory of In-Memory Computing Chips(2024B1212020002)the Shenzhen Science and Technology Program(KJZD20230923115005009)。
文摘Reed membrane,a natural cellulosic material traditionally used in musical instruments,holds promise in flexible electronics due to its abundance,low cost,and excellent biocompatibility.However,its native form contains water-soluble ions and lipid-soluble waxes that hinder performance in acoustic and electronics by compromising electrical insulation and mechanical stability.Here,supercritical fluid superposition purification(SCSP-WA)is introduced,which utilizes supercritical CO_(2)with water and acetone as bipolar co-solvents to selectively remove these impurities.Post-SCSP-WA treatment,the reed membrane exhibits significant enhancements in mechanical strength and electrical insulation,achieving a 4-fold increase in elongation at break,improved tensile strength and Young’s modulus,and a 98.5%reduction in leakage current,all while maintaining low and stable capacitance.These improvements stem from the restructuring of the fibrous network into a porous,interconnected microstructure.Material characterization(X-ray photoelectron spectroscopy(XPS),Fourier-transform infrared spectroscopy(FTIR),and scanning electron microscopy(SEM))confirmed the effective removal of magnesium and waxy functional groups,along with enhanced fiber crosslinking.Cytotoxicity tests further validated the biocompatibility of the SCSP-WA-treated membranes.This environmentally sustainable approach expands the potential of reed membranes in flexible bioelectronics and bio-integrated acoustic systems.
