ZnO nanowires(ZnO NWs),ZnO nanoparticles(ZnO NPs)and carbon dots(C-dots)were synthesized by hydrothermal,sol-gel and hydrothermal methods respectively.They were also characterized and applied for dye sensitized solar ...ZnO nanowires(ZnO NWs),ZnO nanoparticles(ZnO NPs)and carbon dots(C-dots)were synthesized by hydrothermal,sol-gel and hydrothermal methods respectively.They were also characterized and applied for dye sensitized solar cells(DSSCs).The effects of C-dots on ZnO NWs and ZnO NPs have been evaluated.The C-dots were used at a mole ratio of citric acid(CA)to ethylene diamine(EDA)of 1:1.5.These C-dots were found to enhance the performance of the flexible electrode DSSCs.After the addition of C-dots,the power conversion efficiency(PCE)of ZnO NPs was boosted to be two times higher than that of ZnO NPs DSSCs without C-dots.Similarly,the ultraviolet(UV)-band revealed a blue shift,resulting in a lower band gap and a reduced charge transfer resistance,which can enhance the PCE of DSSCs.The loaded quantity on the flexible electrode substrate made of polyethylene terephthalate(PET)was optimized(50 mg).For DSSCs,the PET flexible electrode conductive polymer has produced positive outcomes.For ZnO NWs and ZnO NWs@C-dots,the PCE values were 1.45%and 4.25%;while for ZnO NPs and ZnO NPs@C-dots,they were 2.34%and 5.81%,respectively.This work achieved remarkable and competitive performance when compared to solid(indium tin oxides/glass)-based substrate.展开更多
With the spectacular rise of wearable and portable electronics,flexible power supplying systems with robust mechanical flexibility and high energy storage performance under various mechanical deformation conditions ar...With the spectacular rise of wearable and portable electronics,flexible power supplying systems with robust mechanical flexibility and high energy storage performance under various mechanical deformation conditions are imperative to be needed.Sodium ion batteries(SIBs)with sustainable natural abundance,low cost and superb properties similar to equivalent lithium ion batteries(LIBs),which have shown significant potentials as energy source for flexible electronic devices.In this review,the recent advances in flexible electrode materials based on different types of conductive substrates are addressed and the strategies underlying rational design for flexible structures are highlighted,as well as their applications in flexible SIBs.The remaining key challenges in rational electrodes design are discussed,and perspectives for practical applications of flexible SIBs are proposed as general guidance for future research of high-performance flexible SIBs.展开更多
An electromagnetic coupling mathematical model is established by finite element method and is verified by the contrastive experiments of copper matrix Ni-TiN cylindrical coating electrode,copper electrode and Cu50 W e...An electromagnetic coupling mathematical model is established by finite element method and is verified by the contrastive experiments of copper matrix Ni-TiN cylindrical coating electrode,copper electrode and Cu50 W electrode.The wear mechanism of Ni-TiN/Cu composite electrode in the case of high-frequency pulse current is studied,and the influence of the fluctuation frequency of discharge current on electrode wear in micro-EDM is found out.Compared with the electrode made from homogeneous material,the high frequency electromagnetic properties of Ni-TiN composite layer can be used effectively to inhibit the effect of high frequency pulse on the electrode and improve the distribution trend of current density.展开更多
Traditional processes for machining mold cavities are lengthy and costly. EDM (electro-discharge machining) is the most commonly used technique to obtain complex mold cavities. However, some electrodes are difficult t...Traditional processes for machining mold cavities are lengthy and costly. EDM (electro-discharge machining) is the most commonly used technique to obtain complex mold cavities. However, some electrodes are difficult to fabricate because of the complexity. Applying RP (rapid prototyping) technology to fabricate an abrading tool which is used to abrade graphite EDM electrodes, the cost and cycle time can greatly be reduced. The paper describes the work being conducted in this area by the authors. This technique will find widespread application in rapid steel mold manufacturing.展开更多
The recent rapid growth in electronics has reached the point where there is a need for solid-state devices with excellent physical flexibility, which will be a significant advantage in modern electronic devices. In ...The recent rapid growth in electronics has reached the point where there is a need for solid-state devices with excellent physical flexibility, which will be a significant advantage in modern electronic devices. In particular, metal nanowires and nano-particles are chosen for electrodes because of their low resistance and high mechanical stability. Among the various alternatives, Ag nanomaterials have recently garnered increasing attention due to the high intrinsic conductivity, a transparency with a low sheet resistance and relatively low cost. We herein summarize recent developments toward flexible electronics on the basis of Ag nanomaterials , which show promising performance and outperform the commonly used. The typical fabrication techniques along with the promising applications for flexible devices, are thoroughly discussed.展开更多
Flexible electrodes have been widely focused on in recent years due to their special mechanical properties,which can be directly integrated onto human soft tissues to actively take effects on human body or passively m...Flexible electrodes have been widely focused on in recent years due to their special mechanical properties,which can be directly integrated onto human soft tissues to actively take effects on human body or passively monitor human vital signs.These flexible electrodes provide a new routine to realize clinical treatment of accurate thermal ablation in the biological tissues via radiofrequency ablation(RFA).Meanwhile,accurately controlling of thermal field is very significant for the thermal ablation in the clinical therapeutics to prevent the healthy tissue from excessive burning.In this paper,both one-dimensional and two-dimensional axisymmetric analytical models for the electrothermal analysis of radiofrequency ablation considering bio-heat transfer are established,which are verified by finite element analysis(FEA)and in vitro experiments on pig skins.In the model,the electrical field and thermal field are both derived analytically to accurately predict the temperature rise in the biological tissues.Furthermore,parameters,such as the blood flow convection in living tissues and thickness of tissue,have obvious effects on the thermal field in the tissues.They may pave the theoretical foundation and provide guidance of RFA with flexible electrodes in the future.展开更多
Direct current and pulse plating of copper-zirconium diboride (ZrB2) composites were studied and the effects of current density (DC) and pulse duty cycle (PC) on the EDM performance of the composites were invest...Direct current and pulse plating of copper-zirconium diboride (ZrB2) composites were studied and the effects of current density (DC) and pulse duty cycle (PC) on the EDM performance of the composites were investigated. With increasing current density, the effect of grain refinement on the electro-discharge machining (EDM) performance of the composites compensates that of the decrease of ZrB2 content in the composites, which improves the spark-resistance of the material. Under the same average current density and other experiment conditions, a lower duty cycle yields better EDM performance probably because more ZrB2 particles are incorporated in the composites in this condition. However, at a still lower duty cycle (10%), the particle agglomeration and the microcracks of the copper matrix occur, which considerably deteriorate the spark-resistance of the composites.展开更多
The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the cr...The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the creation of hierarchical structures with distinctive func-tionalities,remains a formidable challenge.Here,we present a method for nanomaterial assembly enhanced by ionic liquids,which enables the fabrication of highly stable,flexible,and transparent electrodes featuring an organized layered structure.The utilization of hydrophobic and non-volatile ionic liquids facilitates the production of stable interfaces with water,effectively preventing the sedimentation of 1D/2D nanomaterials assembled at the interface.Furthermore,the interfacially assembled nanomaterial monolayer exhibits an alternate self-climbing behavior,enabling layer-by-layer transfer and the formation of a well-ordered MXene-wrapped silver nanowire network film.The resulting composite film not only demonstrates exceptional photoelectric performance with a sheet resistance of 9.4Ωsq^(-1) and 93%transmittance,but also showcases remarkable environmental stability and mechanical flexibility.Particularly noteworthy is its application in transparent electromagnetic interference shielding materials and triboelectric nanogenerator devices.This research introduces an innovative approach to manufacture and tailor functional devices based on ordered nanomaterials.展开更多
Smart wearable devices are regarded to be the next prevailing technology product after smartphones and smart homes,and thus there has recently been rapid development in flexible electronic energy storage devices.Among...Smart wearable devices are regarded to be the next prevailing technology product after smartphones and smart homes,and thus there has recently been rapid development in flexible electronic energy storage devices.Among them,flexible solid-state zinc-air batteries have received widespread attention because of their high energy density,good safety,and stability.Efficient bifunctional oxygen electrocatalysts are the primary consideration in the development of flexible solid-state zinc-air batteries,and self-supported air cathodes are strong candidates because of their advantages including simplified fabrication process,reduced interfacial resistance,accelerated electron transfer,and good flexibility.This review outlines the research progress in the design and construction of nanoarray bifunctional oxygen electrocatalysts.Starting from the configuration and basic principles of zinc-air batteries and the strategies for the design of bifunctional oxygen electrocatalysts,a detailed discussion of self-supported air cathodes on carbon and metal substrates and their uses in flexible zinc-air batteries will follow.Finally,the challenges and opportunities in the development of flexible zinc-air batteries will be discussed.展开更多
In recent years,the rapid development of portable/wearable electronics has created an urgent need for the development of flexible energy storage devices.Flexible lithium-ion batteries(FLIBs)have emerged as the most at...In recent years,the rapid development of portable/wearable electronics has created an urgent need for the development of flexible energy storage devices.Flexible lithium-ion batteries(FLIBs)have emerged as the most attractive and versatile flexible electronic storage devices available.Carbon nanotubes(CNTs)are hollow-structured tubular nanomaterials with high electrical conductivity,large specific surface area,and excellent mechanical properties.Graphene(G)is to some extent comparable to CNTs,because both have unlimited value in flexible electrodes.Herein,a systematic summary of the application of CNT and G in FLIBs electrodes is presented,including different functional applications and services at different temperatures.Furthermore,the effects of electrode structures,including powder,wire-shaped,and film-shaped structures,on electrochemical properties is highlighted.The assembly structures of the FLIBs consisting of CNT and G-based flexible electrodes to realize different functions,including bendability,stretchability,foldability,self-healing,and self-detecting,are systematically reviewed.The current challenges and development prospects of flexible CNT and G-based flexible electrodes and corresponding FLIBs are discussed.展开更多
文摘ZnO nanowires(ZnO NWs),ZnO nanoparticles(ZnO NPs)and carbon dots(C-dots)were synthesized by hydrothermal,sol-gel and hydrothermal methods respectively.They were also characterized and applied for dye sensitized solar cells(DSSCs).The effects of C-dots on ZnO NWs and ZnO NPs have been evaluated.The C-dots were used at a mole ratio of citric acid(CA)to ethylene diamine(EDA)of 1:1.5.These C-dots were found to enhance the performance of the flexible electrode DSSCs.After the addition of C-dots,the power conversion efficiency(PCE)of ZnO NPs was boosted to be two times higher than that of ZnO NPs DSSCs without C-dots.Similarly,the ultraviolet(UV)-band revealed a blue shift,resulting in a lower band gap and a reduced charge transfer resistance,which can enhance the PCE of DSSCs.The loaded quantity on the flexible electrode substrate made of polyethylene terephthalate(PET)was optimized(50 mg).For DSSCs,the PET flexible electrode conductive polymer has produced positive outcomes.For ZnO NWs and ZnO NWs@C-dots,the PCE values were 1.45%and 4.25%;while for ZnO NPs and ZnO NPs@C-dots,they were 2.34%and 5.81%,respectively.This work achieved remarkable and competitive performance when compared to solid(indium tin oxides/glass)-based substrate.
基金financially supported by the National Natural Science Foundation of China(52101267)the China Postdoctoral Science Foundation(2021M690117)。
文摘With the spectacular rise of wearable and portable electronics,flexible power supplying systems with robust mechanical flexibility and high energy storage performance under various mechanical deformation conditions are imperative to be needed.Sodium ion batteries(SIBs)with sustainable natural abundance,low cost and superb properties similar to equivalent lithium ion batteries(LIBs),which have shown significant potentials as energy source for flexible electronic devices.In this review,the recent advances in flexible electrode materials based on different types of conductive substrates are addressed and the strategies underlying rational design for flexible structures are highlighted,as well as their applications in flexible SIBs.The remaining key challenges in rational electrodes design are discussed,and perspectives for practical applications of flexible SIBs are proposed as general guidance for future research of high-performance flexible SIBs.
基金the National Natural Science Foundation of China for financially supporting this research through project No.51005027
文摘An electromagnetic coupling mathematical model is established by finite element method and is verified by the contrastive experiments of copper matrix Ni-TiN cylindrical coating electrode,copper electrode and Cu50 W electrode.The wear mechanism of Ni-TiN/Cu composite electrode in the case of high-frequency pulse current is studied,and the influence of the fluctuation frequency of discharge current on electrode wear in micro-EDM is found out.Compared with the electrode made from homogeneous material,the high frequency electromagnetic properties of Ni-TiN composite layer can be used effectively to inhibit the effect of high frequency pulse on the electrode and improve the distribution trend of current density.
基金The work in this paper is supported by NSFC fund under the contract No.59775066.
文摘Traditional processes for machining mold cavities are lengthy and costly. EDM (electro-discharge machining) is the most commonly used technique to obtain complex mold cavities. However, some electrodes are difficult to fabricate because of the complexity. Applying RP (rapid prototyping) technology to fabricate an abrading tool which is used to abrade graphite EDM electrodes, the cost and cycle time can greatly be reduced. The paper describes the work being conducted in this area by the authors. This technique will find widespread application in rapid steel mold manufacturing.
基金Program for the Top Young Academic Leaders of Higher Learning Institutions of Shanxi,100 Persons Program of Shanxithe Project Supported by Science Foundation of North University of China(No.110248-28140)The Project Supported by Science and Technology on Electronic Test & Measurement Laboratory(No.110103112113)
文摘The recent rapid growth in electronics has reached the point where there is a need for solid-state devices with excellent physical flexibility, which will be a significant advantage in modern electronic devices. In particular, metal nanowires and nano-particles are chosen for electrodes because of their low resistance and high mechanical stability. Among the various alternatives, Ag nanomaterials have recently garnered increasing attention due to the high intrinsic conductivity, a transparency with a low sheet resistance and relatively low cost. We herein summarize recent developments toward flexible electronics on the basis of Ag nanomaterials , which show promising performance and outperform the commonly used. The typical fabrication techniques along with the promising applications for flexible devices, are thoroughly discussed.
基金The authors acknowledge the supports from the National Natural Science Foundation of China(No.11772030)the Aeronautical Science Foundation of China(No.2018ZC51030).
文摘Flexible electrodes have been widely focused on in recent years due to their special mechanical properties,which can be directly integrated onto human soft tissues to actively take effects on human body or passively monitor human vital signs.These flexible electrodes provide a new routine to realize clinical treatment of accurate thermal ablation in the biological tissues via radiofrequency ablation(RFA).Meanwhile,accurately controlling of thermal field is very significant for the thermal ablation in the clinical therapeutics to prevent the healthy tissue from excessive burning.In this paper,both one-dimensional and two-dimensional axisymmetric analytical models for the electrothermal analysis of radiofrequency ablation considering bio-heat transfer are established,which are verified by finite element analysis(FEA)and in vitro experiments on pig skins.In the model,the electrical field and thermal field are both derived analytically to accurately predict the temperature rise in the biological tissues.Furthermore,parameters,such as the blood flow convection in living tissues and thickness of tissue,have obvious effects on the thermal field in the tissues.They may pave the theoretical foundation and provide guidance of RFA with flexible electrodes in the future.
基金This work was financially supported by the National Natural Science Foundation of China (No. 59935110)the Science Founda-tion of Liaoning Province, China (No. 20062183).
文摘Direct current and pulse plating of copper-zirconium diboride (ZrB2) composites were studied and the effects of current density (DC) and pulse duty cycle (PC) on the EDM performance of the composites were investigated. With increasing current density, the effect of grain refinement on the electro-discharge machining (EDM) performance of the composites compensates that of the decrease of ZrB2 content in the composites, which improves the spark-resistance of the material. Under the same average current density and other experiment conditions, a lower duty cycle yields better EDM performance probably because more ZrB2 particles are incorporated in the composites in this condition. However, at a still lower duty cycle (10%), the particle agglomeration and the microcracks of the copper matrix occur, which considerably deteriorate the spark-resistance of the composites.
基金This work was supported by the National Natural Science Foundation of China(nos.21988102,and 22305026)the China Postdoctoral Science Foundation(2019M650433).
文摘The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the creation of hierarchical structures with distinctive func-tionalities,remains a formidable challenge.Here,we present a method for nanomaterial assembly enhanced by ionic liquids,which enables the fabrication of highly stable,flexible,and transparent electrodes featuring an organized layered structure.The utilization of hydrophobic and non-volatile ionic liquids facilitates the production of stable interfaces with water,effectively preventing the sedimentation of 1D/2D nanomaterials assembled at the interface.Furthermore,the interfacially assembled nanomaterial monolayer exhibits an alternate self-climbing behavior,enabling layer-by-layer transfer and the formation of a well-ordered MXene-wrapped silver nanowire network film.The resulting composite film not only demonstrates exceptional photoelectric performance with a sheet resistance of 9.4Ωsq^(-1) and 93%transmittance,but also showcases remarkable environmental stability and mechanical flexibility.Particularly noteworthy is its application in transparent electromagnetic interference shielding materials and triboelectric nanogenerator devices.This research introduces an innovative approach to manufacture and tailor functional devices based on ordered nanomaterials.
基金supported by the National Natural Science Foundation of China(22072107,21872105)the Natural Science Foundation of Shanghai(23ZR1464800)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Science&Technology Commission of Shanghai Municipality(19DZ2271500)。
文摘Smart wearable devices are regarded to be the next prevailing technology product after smartphones and smart homes,and thus there has recently been rapid development in flexible electronic energy storage devices.Among them,flexible solid-state zinc-air batteries have received widespread attention because of their high energy density,good safety,and stability.Efficient bifunctional oxygen electrocatalysts are the primary consideration in the development of flexible solid-state zinc-air batteries,and self-supported air cathodes are strong candidates because of their advantages including simplified fabrication process,reduced interfacial resistance,accelerated electron transfer,and good flexibility.This review outlines the research progress in the design and construction of nanoarray bifunctional oxygen electrocatalysts.Starting from the configuration and basic principles of zinc-air batteries and the strategies for the design of bifunctional oxygen electrocatalysts,a detailed discussion of self-supported air cathodes on carbon and metal substrates and their uses in flexible zinc-air batteries will follow.Finally,the challenges and opportunities in the development of flexible zinc-air batteries will be discussed.
基金supported by the National Natural Science Foundation of China(Grant Nos.51972261 and 51302206)。
文摘In recent years,the rapid development of portable/wearable electronics has created an urgent need for the development of flexible energy storage devices.Flexible lithium-ion batteries(FLIBs)have emerged as the most attractive and versatile flexible electronic storage devices available.Carbon nanotubes(CNTs)are hollow-structured tubular nanomaterials with high electrical conductivity,large specific surface area,and excellent mechanical properties.Graphene(G)is to some extent comparable to CNTs,because both have unlimited value in flexible electrodes.Herein,a systematic summary of the application of CNT and G in FLIBs electrodes is presented,including different functional applications and services at different temperatures.Furthermore,the effects of electrode structures,including powder,wire-shaped,and film-shaped structures,on electrochemical properties is highlighted.The assembly structures of the FLIBs consisting of CNT and G-based flexible electrodes to realize different functions,including bendability,stretchability,foldability,self-healing,and self-detecting,are systematically reviewed.The current challenges and development prospects of flexible CNT and G-based flexible electrodes and corresponding FLIBs are discussed.