Copper Wire Research Articles

Local Electric Field-Incorporated In-Situ Copper Ions Eliminating Pathogens and Antibiotic Resistance Genes in Drinking Water

Background/Objectives: Pathogen inactivation and harmful gene destruction from water just before drinking is the last line of defense to protect people from waterborne diseases. However, commonly used disinfection methods, such as chlorination, ultraviolet irradiation, and membrane filtration, experience several challenges such as continuous chemical dosing, the spread of antibiotic resistance genes (ARGs), and intensive energy consumption. Methods: Here, we perform a simultaneous elimination of pathogens and ARGs in drinking water using local electric fields and in-situ generated trace copper ions (LEF-Cu) without external chemical dosing. A 100-μm thin copper wire placed in the center of a household water pipe can generate local electric fields and trace copper ions near its surface after an external low voltage is applied. Results: The local electric field rapidly damages the outer structure of microorganisms through electroporation, and the trace copper ions can effectively permeate the electroporated microorganisms, successfully damaging their nucleic acids. The LEF-Cu disinfection system achieved complete inactivation (>6 log removal) of Escherichia coli O157:H7, Pseudomonas aeruginosa PAO1, and bacteriophage MS2 in drinking water at 2 V for 2 min, with low energy consumption (10−2 kWh/m3). Meanwhile, the system effectively damages both intracellular (0.54~0.64 log) and extracellular (0.5~1.09 log) ARGs and blocks horizontal gene transfer. Conclusions: LEF-Cu disinfection holds promise for preventing horizontal gene transfer and providing safe drinking water for household applications.

The aluminum and titanium-doped zinc oxide films with improved blocking effect on copper diffusion

Low-cost transparent conductive oxide films and copper metallization play a crucial role in the advancement of silicon heterojunction technologies (SHJ) to the terawatt level. However, the mechanisms of interfacial diffusion of copper through a zinc-based transparent conductive oxides (TCO) layer into silicon are still not known. In this study, we report that for the aluminum and titanium-doped zinc oxide (ATZO) films prepared by the magnetron sputtering method in the n-Si/110 nm TCOs/50 nm Cu structure, compared with indium tin oxide (ITO) and aluminum-doped zinc oxide (AZO), the blocking effect on copper diffusion can be comparable to that of ITO more than that of AZO. The results show that the measured band gap value of ATZO is 3.64 eV, and in terms of carrier concentration, ATZO has a value of 3.7 × 1020 cm−3, which is much higher than the level of AZO. The sample with an ATZO layer also outperforms AZO in band gap, surface morphology, and conductivity, even after heat treatment up to 600 °C. It is important to note, however, that the high-temperature annealing used in this study may have induced changes in the crystallinity and alloy composition of the TCOs, which are not representative of typical SHJ operating conditions. Further studies with more moderate annealing temperatures are needed to better simulate real-world conditions. Nevertheless, ATZO films show strong potential as effective copper diffusion barriers in low-cost metallized photovoltaic applications, offering performance on par with ITO

ACOUSTIC-MODELING OF RANDOM FIBROUS MATERIALS

We present a microstructure-based model for determining the sound absorption behavior and transport parameters of random fibrous materials and exploring the physical mechanisms underlying acoustic energy dissipation. In order to increase the generalizability of the model, a three-dimensional random fiber structure is employed for simulation. The propagation of sound waves is associated with four transport parameters, including viscous permeability, tortuosity, as well as viscous and thermal characteristic lengths. These parameters are determined by the porosity and diameter of the fibrous material. By using the method of multi-scale asymptotic simulation, the theoretical model for transport parameters includes unknown coefficients that are adjusted based on the simulated results. The sound absorption coefficients are then obtained by integrating the transport parameters into the widely-used Johnson-Champoux-Allard (JCA) model for porous materials. The theoretical predictions match well with existing experimental measurements on sintered fiber metals and fibrous copper wires. Our model systematically examines the impact of fiber diameter, porosity, and material thickness on sound absorption performance. Optimal results are achieved by carefully selecting fiber diameter and porosity to enhance the acoustic dissipation of sound waves, while thicker fibrous materials increase sound absorption in the low frequency range. The model provides a theoretical framework for designing and fabricating fibrous materials to reduce noise.

Continuous fiber printing of a modular heater for ion mobility spectrometry

Ion mobility spectrometry (IMS) is a powerful analytical method for separating and detecting gaseous substances like volatile organic compounds (VOCs). It is highly versatile, used both as a standalone technique and in combination with chromatographic methods for pre-separation or mass spectrometry for complex matrix analysis. This study explores the use of an advanced 3D printing technology to print a heater for an IMS-device.A continuous fiber printer, commonly used to enhance the mechanical properties of printed objects, was used to create a customized heating element by embedding a copper wire within the polymer matrix during the printing process. Cyclic olefin copolymer (COC) was chosen as the matrix material due to its analytical properties, such as low off-gassing and higher thermal stability, compared to the more commonly used polylactic acid (PLA).The 3D printed heater was incorporated into a drift tube ion mobility spectrometer, and its performance was evaluated by analyzing the separation of various ketones. The results show that the 3D printed heater effectively controlled the temperature within the drift tube, improving the resolving power of overlapping peaks.This study shows the potential of 3D printing technology to improve fabrication and functionality of IMS devices. The flexibility in design and material selection afforded by 3D printing not only enhances the analytical performance of IMS but also allows for customization and rapid prototyping of other analytical instruments or laboratory devices.

In Situ Synthesis of Nitrogen-Doped Carbon Coated Copper: Boosting Superhydrophobicity, Conductivity, and Oxidation Resistance.

Copper (Cu), known for its excellent electrical and thermal conductivity, faces significant challenges due to its susceptibility to oxidation, which leads to the formation of nonconductive oxide layers that impair its performance. We present an in situ thermal reduction method to synthesize nitrogen-doped carbon coated copper (NC@Cu) with enhanced oxidation and corrosion resistance. Using a stable, nontoxic, and cost-effective dopamine derivative, catechol (CA), and phenylenediamine, we developed a polydopamine-like (PDL) coating on copper oxide (CuO). Upon pyrolysis under an inert atmosphere, this coating transforms into a nitrogen-doped carbon layer, while simultaneously reducing CuO to metallic Cu in a stepwise process, initially forming Cu2O and then fully reducing to Cu. The resulting NC@Cu exhibits remarkable superhydrophobicity, enhanced conductivity, and exceptional resistance to oxidation and corrosion, attributed to the protective dense carbon layer. This study provides insights into the synergistic processes of PDL conversion into nitrogen-doped carbon and CuO reduction to Cu, offering a straightforward and practical passivation method for producing electrically conductive and oxidation-resistant copper with potential applications in harsh environments.

A novel method for introducing asymmetry in pulsating heat pipes to enhance performance

The primary objective of this study is to improve the performance of a pulsating heat pipe (PHP) by introducing a novel method of incorporating asymmetry into the PHP design. This asymmetry is achieved by inserting a copper wire into one column of a single-loop PHP. Five different configurations of single-loop PHPs were created for this study: one with a uniform internal diameter (ID) of 2.5 mm (UPHP), one with dual diameters (2.5 mm and 1.8 mm ID) (DPHP), and three with a uniform ID of 2.5 mm but with varying wire diameters (0.7 mm, 1.2 mm, and 1.7 mm) inserted into one column (WAPHP). The PHPs were constructed using borosilicate glass. The performance of these PHPs was evaluated through visualization techniques and by calculating equivalent thermal resistance. A comprehensive study was conducted by varying filling ratios, inclination angles, and heat loads to understand their influence on PHP performance. The results indicate that at a 60% filling ratio, the wired asymmetric pulsating heat pipe (WAPHP) with a 1.2 mm diameter wire exhibited superior performance compared to all other tested configurations achieving a thermal resistance of 1.27 K/W. The WAPHP performed effectively up to an inclination angle of 15°. Additionally, the WAPHP with a 1.7 mm wire diameter demonstrated the earliest startup, taking just 35 s, and showed the maximum heat load capacity at a 50% filling ratio in a vertical orientation. Furthermore, dry-out did not occur in the 1.2 mm and 1.7 mm diameter WAPHPs at 50% and 60% filling ratios up to the tested heat load.

ZnO nanorods grown on Cu wire mesh provide a high sensitivity non-enzymatic absorbance glucose sensor.

Ahighly sensitive non-enzymatic absorption-based glucose sensor is introducedthat combines ZnO nanorods with the ferrous oxidation-xylenol orange (FOX) assay. ZnO nanorods were successfully synthesized on the surface of a copper wire mesh, exhibiting high crystallinity, purity, and a large surface area. The glucose sensor displays a high sensitivity of 0.394mM-1 in a wide linear detection range (0 - 6mM), along with a low limit of detection of 0.25mM. The proposed assay has an excellent selectivity towards glucose comparedwithother sugars such as sucrose, maltose, and fructose. The potential use of the non-enzymatic absorbance sensor for diabetes monitoring is demonstrated by measuring the glucose concentration in human blood serum, obtaining values that are consistent with clinical analysis.

A cost-effective load side management solution based on power line carrier communication i-PLCC.

Conventional power systems are almost at the verge of their existence and are quickly being replaced by modern, especially smarter alternatives. Rapid and wide deployment of Load side management, which is a smarter and modern way to ensure efficient and economical use of power, is a classic example. However, there are several challenges which need to be addressed before it can be realized as a commercially viable solution. Suitable communication method, called "Home Area Networks", is a mandatory requirement which should be cost effective, robust and with ability to simultaneously handle large number of devices. Due to various inherent issues, communication protocols commonly used now-a-days, are not fully capable to address the requirements of HANs. Power Line Carrier Communications (PLCC) can be a suitable and efficient alternative of quick realization of HANs. In this paper, various aspects of PLCC have been analyzed for use in HANs. Modulation methods, materials, physical parameters and effect of noise have been analyzed. The paper evaluates performance and effectiveness of FSK modulation with aluminum transmission medium for PLC within a residential environment, focusing on the tradeoffs between distance, transmission medium diameter, and type of transmission medium, and cable gauge, which can degrade the performance of PLCC. A novel simulation model has been presented incorporating RLCG (Resistance, Inductance, Capacitance, and Conductance) tools and additive white Gaussian noise (AWGN). Performance parameter have been comprehensively analyzed of implementation using aluminum as a communication medium. This paper discusses cost effectiveness of PLCC by replacing copper by aluminum as the transmission medium. The study reveals that aluminum cables must be twice the size of copper cable in order to achieve same communication distances. Higher carrier frequencies in FSK modulation increase noise susceptibility, consequently reducing achievable communication distances. Cables with smaller diameters results in lower transmission ranges. These results highlight the trade-offs involved in implementing FSK for in-home PLCC (iPLCC). The study highlights how crucial it is to take these trade-offs into account while developing and refining FSK-based iPLCC systems for use in smart homes.

Copper Winding Voice Coil Speaker Microcontroller Based

The voice coil is a vital speaker component, producing sound through electromagnetic vibrations. Generally, commercially available voice coils do not meet standard quality specifications, especially in terms of copper quality and adhesive strength. This problem often leads to issues such as coil burning or breakage during operation. On the other hand, ordering custom voice coils through manual winding processes requires considerable time. This study aims to address these limitations by designing an automated coil winding device that employs Pulse Width Modulation (PWM) techniques to control the speed of a DC motor, enabling the production of voice coils with specifications and durability tailored to specific needs. An Arduino Nano microcontroller controls the system and consists of a BTS 7960 motor driver, a Direct Current (DC) motor, an optocoupler sensor, a rotary encoder, a 4x4 keypad, and an LCD display with an I2C interface. Coil durability testing was conducted using an ohmmeter and an amplifier with a transformer ranging from 20A 45V to 30A 45V. The testing results indicate that coils produced with the automated winder can be adjusted to approach the 8-ohm specification, with a tolerance of 0.1 to 0.3 ohms, suitable for speaker requirements. The comparison results show that commercial voice coils exhibit resistances below 8 ohms, with the lowest resistance measured at 4.9 ohms for larger coils. During power testing, coils with a diameter of 35.5 mm and copper wire diameters of 0.20 mm and 0.23 mm broke when tested with a 20A 45V amplifier. In contrast, commercial coils remained stable up to an input power of 372 W and output power of 273 W, although a burning odor was detected. These findings indicate that the copper quality in commercial coils is superior in resisting amplifier power up to 30A 45V compared to coils produced with the automated device.

Evaluation of Continuous GMA Welding Characteristics Based on the Copper-Plating Method of Solid Wire Surfaces

Gas metal arc welding (GMAW) is widely used in various industries, such as automotive and heavy equipment manufacturing, because of its high productivity and speed, with solid wires being selected based on the mechanical properties required for welded joints. GMAW consists of various components, among which consumables such as the contact tip and continuously fed solid wire have a significant impact on the weld quality. In particular, the copper-plating method can affect the conductivity and arc stability of the solid wire, causing differences in the continuous welding performance. This study evaluated the welding performance during 60 min continuous GMAW using an AWS A5.18 ER70S-3 solid wire, which was copper-plated using chemical plating (C-wire) and electroplating (E-wire). The homogeneity and adhesion of the copper-plated surface of the E-wire were superior to those of the C-wire. The E-wire exhibited better performance in terms of arc stability. The wear rate of the contact tip was approximately 45% higher when using the E-wire for 60 min of welding compared with the C-wire, which was attributed to the larger variation rate in the cast and helix in the E-wire. Additionally, the amount of spatter adhered to the nozzle during 60 min, with the E-wire averaging 5.9 g, approximately half that of the C-wire at 12.9 g. The E-wire exhibits superior arc stability compared with the C-wire based on the spatter amount adhered to the nozzle. This study provides an important reference for understanding the impact of copper plating methods and wire morphology on the replacement cycles of consumable welding parts in automated welding processes such as continuous welding and wire-arc additive manufacturing.

Obtaining Symmetrical Gradient Structure in Copper Wire by Combined Processing

Traditionally, structural wire is characterized by a homogeneous microstructure, where the average grain size in different parts of the wire is uniform. According to the classical Hall–Petch relationship, a homogeneous polycrystalline metal can be strengthened by decreasing the average grain size since an increase in the volume fraction of grain boundaries will further impede the motion of dislocations. However, a decrease in the grain size inevitably leads to a decrease in the ductility and deformability of the material due to limited dislocation mobility. Putting a gradient microstructure into the wire has promising potential for overcoming the compromise between strength and ductility. This is proposed a new combined technology in this paper in order to obtain a gradient microstructure. This technology consists of deforming the wire in a rotating equal-channel step die and subsequent traditional drawing. Deformation of copper wire with a diameter of 6.5 mm to a diameter of 5.0 mm was carried out in three passes at room temperature. As a result of such processing, a gradient microstructure with a surface nanostructured layer (grain size ~400 nm) with a gradual increase in grain size towards the center of the wire was obtained. As a result, the microhardness in the surface zone was 1150 MPa, 770 Mpa in the neutral zone, and 685 MPa in the central zone of the wire. Such a symmetrical spread of microhardness, observed over the entire cross-section of the rod, is a direct confirmation of the presence of a gradient microstructure in deformed materials. The strength characteristics of the wire were doubled: the tensile strength increased from 335 MPa to 675 MPa, and the yield strength from 230 MPa to 445 MPa. At the same time, the relative elongation decreased from 20% to 16%, and the relative contraction from 28% to 23%. Despite the fact that the ductility of copper is decreased after cyclic deformation, its values remain at a fairly high level. The validity of all results is confirmed by numerous experiments using a complex of traditional and modern research methods, which include optical, scanning, and transmission microscopy; determination of mechanical properties under tension; and measurement of hardness and electrical resistance. These methods allow reliable interpretation of the fine microstructure of the wire and provide information on its strength, plastic, and electrical properties.

Microstructure, electrical resistivity, and tensile properties of neutron-irradiated Cu–Cr–Nb–Zr

High strength, high conductivity copper alloys that can resist creep at high temperatures are one of the primary candidates for efficient heat exchangers in fusion reactors. Cu–Cr–Nb–Zr (CCNZ) alloys, which were designed to improve the strength and creep life of ITER Cu–Cr–Zr (CCZ) reference alloys, have been found to have comparable electrical conductivity and tensile properties to CCZ alloys. The measured creep rupture times for these improved alloys is about ten times higher than the ITER reference alloys at 90–125 MPa at 500 °C. However, the effects of neutron irradiation on these alloys, and the ensuing material properties, have not been studied; thus, their utility in a fusion reactor environment is not well understood. This study characterizes the room temperature mechanical and electrical properties of a neutron-irradiated CCNZ alloy and compares them to a neutron-irradiated ITER reference heat sink CCZ alloy. Tensile specimens were neutron irradiated in the High Flux Isotope Reactor (HFIR) to 5 dpa between 250 °C and 325 °C. Post-irradiation characterization included electrical resistivity measurements, hardness, and tensile tests. Microstructural evaluation used scanning electron microscopy, energy dispersive x-ray spectroscopy, and atom probe tomography to characterize the irradiation-produced changes in the microstructure and investigate the mechanistic processes leading to post-irradiation properties. Transmutation calculations were validated with composition measurements from atom probe data and used to calculate contributions to the increased electrical resistivity measured after irradiation. Comparisons with CCZ alloys in the same irradiation heat found that the post-irradiated CCNZ and CCZ alloys had comparable electrical resistivity. Although CCNZ alloys suffered more irradiation hardening than CCZ, the overall tensile behavior deviated very little from non-irradiated values in the temperature range studied.

Al-clad Cu bond wires for power electronics packaging: Microstructure evolution, mechanical performance, and molecular dynamics simulation of diffusion behaviors

With the advancement of power electronics, aluminum-clad copper thick bonding wires have garnered attentions due to superior electrical and thermal properties, making them well-suited for high-temperature and high-current applications. However, the impact remains unveiled of whether the growth of intermetallic compounds (IMCs) at the bonding interface presents critical challenges to the reliability of wedge wire bonds. Therefore, it is necessary to investigate the evolution behavior of Cu/Al IMCs in Al-clad copper wires. In this study, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were firstly employed to characterize the phase composition and growth behavior of Cu/Al intermetallic compounds (IMCs) at two distinct interfaces—the bonding interface and the core-shell interface—under various annealing conditions during high-temperature storage (HTS) tests, revealing a parabolic relationship between aging time and IMCs thickness. Subsequently, shear and pull tests of Al-clad copper bond wires were conducted to evaluate the bonding strength under different aging conditions, clarifying the correlation between various failure modes of the bonds and the evolution of IMCs at the bi-interfaces of this novel composite across different aging stages. Additionally, molecular dynamics (MD) simulations were employed to explore the diffusion behavior of Cu and Al atoms. It revealed that polycrystalline structures enhanced the mutual diffusion at the interface, with copper serving as the predominant element in the interdiffusion process. In conclusion, this study integrates experimental and numerical approaches to elucidate the growth mechanisms of Cu/Al intermetallic compounds and their effects on reliability, providing valuable guidance for optimizing the performance of composite bonding wires in high-temperature power device applications.

In situ synthesis of Cu(OH)2 and carbon nanotube electrodes: A promising approach for high-performance one-dimensional flexible supercapacitors

Amidst the rapid surge in electrical device utilization, there is an urgent need for advanced power supply solutions. Flexible supercapacitors, renowned for their remarkable electrochemical properties, emerge as a promising remedy. This study employs in situ techniques on copper wire (CW) to obtain active materials for both the electrodes. The positive CW@Cu(OH)2 electrode, synthesized through vapor-phase reaction between CW and NH3·H2O, yields copper hydroxide (Cu(OH)2) nanosheets via an alkali-assisted oxidation process. Comparative analysis of CW@Cu(OH)2 electrodes under varying reaction conditions revealed that the Cu(OH)2 nanosheets, characterized by their small size and high distribution density on CW, significantly enhance electrochemical performance. The optimized CW@Cu(OH)2 electrode achieved a specific capacitance of 195.7 mF cm−2. This in situ growth method effectively prevents active material detachment, resulting in electrodes with minimal internal resistance. Carbon nanotubes (CNTs), also synthesized in situ via chemical vapor deposition on CW, serve as the active materials for the negative electrode. Assembled in parallel, the flexible supercapacitor, CW@Cu(OH)2//KOH-PVA//CW@CNTs, achieves a specific capacitance of 1.59 F cm−3 at a current density of 0.1 A cm−3, with an energy density of 0.496 mWh cm−3 at a power density of 15 mW cm−3. Demonstrating robust capacitance retention across varying current densities and diverse bending angles, this supercapacitor signifies a versatile and stable power storage solution.

Влияние структуры и состава технически чистой бескислородной меди различных производителей на ее электропроводность и механические свойства

The composition, structure, electrical conductivity and mechanical properties of oxygen-free copper grade C10100 with a purity of 99.997% produced by Sichuan Huazi Technology Co., Ltd (China) intended for use in the production of niobium-titanium superconductors as a stabilizing component of a multi-filament composite were studied. It was shown that the recrystallization onset temperature of deformed copper samples in the form of wire is about 150 °C, and as a result of collective recrystallization at temperatures above 300 °C, the grain size reaches a value of more than 180 μm. The RRR parameter characterizing the electrical conductivity of copper at the cryogenic temperature of samples in a fully recrystallized state reaches a value of 1300 units, which is three times higher than the level typical for copper grade C10100 produced by leading manufacturers of cryogenic copper for superconductors. Maximum plasticity (up to 50%) of copper wire samples is achieved after short annealing (less than 5 minutes) at a temperature of 300°C. Increasing the annealing temperature to 600°C leads to a decrease in mechanical properties due to grain growth and the well-known effect of temperature plasticity failure.

Insight into the acceleration effect of current-carrying condition on copper conductor atmospheric corrosion

Copper is widely used as conductive components in transmission lines, facing severe corrosion risks. The current passing through copper conductors will significantly affect its corrosion process, yet there is a lack of detailed study on the corrosion mechanism under this specific condition. Thus, this study investigated the effect of direct current current-carrying (DC C-C) conditions on the atmospheric corrosion behavior of copper conductors under thin electrolyte layer (TEL) through electrochemical measurements and corrosion exposure experiments. Results revealed that the presence of DC C-C significantly hastened the corrosion process of copper conductors in the TEL, leading to distinct corrosion patterns at the input and output ends. Furthermore, both the extent of corrosion acceleration and the unevenness of corrosion were positively correlation with the DC C-C level. The above phenomenon was attributed to the special motion of charged particles and paramagnetic substances in TEL under the self-generated magnetic field.

Enhanced electrical and mechanical properties of graphene/copper composite through reduced graphene oxide-assisted coating

Modifying the surface of metallic materials with graphene (Gr) holds significant potential for achieving high electrical conductivity in metal-based composites, leveraging the synergistic effect of the high carrier concentration in metals and the high carrier mobility of Gr. However, the strong van der Waals forces and large specific surface area of Gr sheets often lead to agglomeration in slurrys, adversely affecting the arrangement of Gr layers within the coating structure. In this study, we introduce reduced Gr oxide (rGO) into the Gr slurry to enhance the electrostatic stability and dispersion of Gr sheets through π-π interactions. By precisely controlling the composition of the coating, a compact, low-roughness coating was prepared on the surface of the copper (Cu) wire. The fabricated Gr/rGO/Cu composite wire exhibited a high conductivity of 104.2% IACS, with a tensile strength of 266.1 MPa and the elongation of 36.3%, respectively. This study demonstrates that the addition of rGO improves the dispersibility of Gr in the slurry, leading to a more compact and effective composite structure. The Gr/rGO/Cu composite wires exhibit superior electrical and mechanical properties, making them promising candidates for high-performance applications in electrical and electronic industries.

Enhancing the detection efficiency of the 3D positive ion detector

Enhancing the 3D positive ion detector's efficiency is the objective of this study. The detector finds numerous applications in the fields of radiation biology, radiation dosimetry, radiation protection, radiation measurement etc. Generally, in 3D positive ion detector the cathode used is either high resistive glass or gold coated over ceramic glass. The detector efficiency has been reported as 2%max with high resistive glass cathode material and 9.2%max with gold coated ceramic glass. In the present study, we have significantly improved the detection efficiency by replacing these materials with an oxygen-free high conductivity (OFHC) copper cathode. This modification resulted in a substantial increase in the detector efficiency, reaching a maximum of 31.3%max. The study also presents a comparison between this enhanced performance and the previously reported efficiencies demonstrating the effectiveness of using high conductivity materials to improve ion detection capabilities.

Progress of highly conductive Graphene-reinforced Copper matrix composites: A review

Enhancing the electrical conductivity of metals remains a critical challenge, as it directly determines the transmission efficiency of power electronic systems. Graphene-reinforced metal matrix composites have garnered widespread attention due to their exceptional electrical conductivity and low-temperature coefficient of resistance. This review thoroughly examines the intrinsic physical properties of Graphene and Cu, identifying specific obstacles in developing highly conductive composite materials. Despite the weak van der waals interactions between Graphene and Cu, the work principle and interaction mechanism between Cu and Graphene are elucidated. The primary focus of this review is to explore methods for enhancing the electrical conductivity of Cu/Graphene composites through different design strategies and processing techniques. The more complex and critical factors encompass the quality of raw materials, processing techniques, dimensional precision, crystallographic orientation, and the interfacial properties between Graphene and Cu. The perspectives on the research gap and further development trends of Cu/Gr composites are also discussed.

Fabric‐Reinforced Functional Insoles with Superior Durability and Antifracture Properties for Energy Harvesting and AI‐Empowered Motion Monitoring

AbstractFunctional triboelectric insoles hold promise for advancing self‐powered wearable technologies. However, their durability is compromised by continuous compressive forces and friction, leading to surface abrasion and material fracturing. To address these challenges, an innovative fabric‐reinforced structure combined with a dual‐L backrest design is developed that enhances anti‐fracture capabilities and electric outputs while enabling AI‐empowered motion monitoring. Polydimethylsiloxane (PDMS) is used as the negative triboelectric material with a dual‐L backrest design, while insulated copper wire (icuW) serves as the positive triboelectric material with an annular structure design. These components are intricately nested to enable a multilayered friction pairing. The fabric‐reinforced structure demonstrates excellent compressive rebound resilience, withstanding forces of at least 1000 N. The functional insole, featuring a fabric‐reinforced dual‐L backrest structure (FRdL‐insole), efficiently harvests biomechanical energy with a peak power of 8214 µW and maintains highly consistent performance after 10 washing cycles and 60 000 durability tests. It can power portable electronic devices such as digital watches, calculators, hygrometers, and LEDs. Enhanced with machine learning algorithms, the FRdL‐insole processes sensor signals to monitor human movements, accurately identifying seven distinct motions. This positions the insole as a smart, real‐time, self‐powered tool for activity recognition, showcasing its potential in intelligent wearable technology.