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Steam reforming of methanol is an effective way to provide an on-line hydrogen source for fuel cells. However, due to the poor utilization of the performance of the catalyst, the traditional reformer has the problems of slow start-up, low hydrogen production. Therefore, it is urgent to develop new catalyst loading methods to make full use of the performance of the catalyst. In this paper, a foamed metal with nano copper wire is used for methanol-reformer. The relevant experiments were carried out to investigate the hydrogen production performance of the foam copper reformer based on nano copper wire and the traditional impregnation method. The results showed that compared with the metal foam autocatalysis, the hydrogen concentration in the product of the nano-copper wire reformer could be increased by more than 8 times. What's more, the concentration of hydrogen in the product is twice that of the current widely used impregnation method. Furthermore, this method reduced the start-up time of the reformer. Meanwhile, the best working parameters of nano copper wire methanol-reformer were obtained through experiments. [Display omitted] • An efficient methanol reforming reactor catalyzed by nano copper wire was developed. • The concentration of hydrogen in the product of copper nanofiber foam was increased by more than two times. • Nano structured copper foam can greatly shorten the start-up time of the reformer. • There is an optimum working condition of nano copper wire reformer. [ABSTRACT FROM AUTHOR]

Copper nanowire (Cu NW) networks are recognized for their excellent electrical conductivity and cost-effectiveness, making them a prime choice for transparent conductors. However, their susceptibility to degradation presents a significant challenge in various applications. In this study, we explore the efficacy of depositing Ti3C2 MXene onto copper nanowire (MXene/Cu NW) networks to enhance the stability and performance of Cu NW-based transparent conducting electrodes (TCEs). The results showed a rapid increase in the electrical resistance of bare Cu NW networks within 10 days under ambient conditions, whereas the deposition of Ti3C2 MXene enhanced the stability of the networks up to 10 months under ambient conditions. A significant figure of merit (FoM) of 109 was achieved from the MXene/Cu NW networks compared to only 69 for bare Cu NW networks. The fabricated TCEs also showcased their long-term stability when utilized as transparent thin-film heaters (TTFHs). The TTFHs utilizing MXene/Cu NW networks displayed consistent performance over the course of 1 week when subjected to a bias voltage of 3 V. Furthermore, the TTFHs have also been utilized as flexible human thermotherapy patches and defrosting networks. Our research underscores the potential of MXene/Cu NW electrodes in optoelectronic applications where both high FoM and long-term stability are essential, thereby expanding the possibilities for cost-effective TCEs in a variety of applications. [ABSTRACT FROM AUTHOR]

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Undersea optical communication (UOC) has been considered as the most potential next‐generation underwater wireless communication technology for ocean exploration. Photodetector is the essential component in UOC system, however, the harsh undersea environment like light attenuation and seawater corrosivity restricts the applications of conventional photodetectors. Herein, a novel natural‐electrolyte self‐powered photoelectrochemical (PEC) photodetector based on core‐shell structured Cu@GaN nanowires (NWs) network is demonstrated and direct utilization of seawater. High quality GaN shell is encapsulated on the Cu NWs network through Ga‐coating and high temperature nitridation processes. A Schottky junction along radial direction has formed at the Cu/GaN interface due to the outward diffusion of Cu into the GaN layer. Such a structure provides narrowed band detection on blue light as well as efficient carrier separation. A self‐powered undersea PEC photodetector is designed with a mini‐pipes connected device chamber, which allows direct indrawing of seawater and blue channel light communication (458 nm). This photodetector works stably for UOC in both shallow and deep‐sea conditions in Pacific Ocean area. It shows a high responsivity up to 5.04 mA W−1 and rapid response time of 0.68 ms. This photodetector can be easily integrated to marine equipment without waterproof packaging for the future energy‐saving UOC. [ABSTRACT FROM AUTHOR]

Despite a century of research, the inability to design flexible transparent electrodes with low cost and high stability has been the greatest obstacle in realizing flexible electronics. Herein, we report the growth of self-assembled SnO2 nanoshells on thin copper nanowire (Cu NW) networks using a simple and effective solution method. In addition, the SnO2–Cu NW flexible films exhibit an extremely low sheet resistance of ∼13.6 Ω/sq, with ∼83.5% optical transparency. In harsh environments (such as strong oxidation, heat, and humidity conditions), the films demonstrate excellent resistance stability, which can compete with the resistance stability of noble silver nanowire films. Particularly, the films are robust and able to withstand a high temperature of 210 °C without any deterioration of performance. Employing the outstanding stability of SnO2–Cu NWs, we also demonstrate the macroscopic use of a transparent conductor in a flexible transparent heater. [ABSTRACT FROM AUTHOR]

The overuse of copper-based fertilizers and pesticides over the last few decades has resulted in detrimental risks to our environment. Nano-enabled agrichemicals with a high effective utilization ratio have shown great potential for maintaining or minimizing environmental issues in agriculture. Copper-based nanomaterials (Cu-based NMs) serve as a promising alternative to fungicides. Three types of Cu-based NMs with different morphologies were analyzed for their different antifungal effects on Alternaria alternata in this current study. Compared to commercial copper hydroxide water power (Cu(OH)2 WP), all tested Cu-based NMs, including cuprous oxide nanoparticles (Cu2O NPs), copper nanorods (Cu NRs) and copper nanowires (Cu NWs), especially Cu2O NPs and Cu NWs, showed higher antifungal activity against Alternaria alternata. Its EC50 were 104.24 and 89.40 mg L−1, respectively, achieving comparable activity using a dose approximately 1.6 and 1.9-fold lower. Cu-based NMs could introduce the downregulation of melanin production and soluble protein content. In contrast to trends in antifungal activity, Cu2O NPs showed the strongest power in regulating melanin production and protein content and similarly exhibited the highest acute toxicity to adult zebrafish compared to other Cu-based NMs. These results demonstrate that Cu-based NMs could offer great potential in plant disease management strategies. [ABSTRACT FROM AUTHOR]

Various textile-based composite conductive materials have been extensively applied for wearable and flexible electronics recently owing to their high flexibility and bio-friendliness. Among these textile-based electronics, flexible non-enzymatic glucose sensors have especially attracted attention because they can diagnose human health status by monitoring glucose concentrations in human sweat, tears, and blood. In this paper, reduced graphene oxide (RGO) was in situ synthesized on cotton fabric (CF) by a hydrothermal reduction method to prepare reduced graphene oxide cotton fabrics (RGO/CF). Copper nanowires (CuNWs) were deposited on reduced graphene oxide cotton fabrics by vacuum filtration to obtain copper nanowires/reduced graphene oxide cotton fabrics (CuNW/RGO/CF) and applied to non-enzymatic glucose biosensing. Under the optimized conditions, the CuNW/RGO/CF sensor exhibits excellent catalytic performance for glucose oxidation and a series of excellent properties, such as the rapid response time and high sensitivity at 1020 μA mM−1 cm−2. Glucose concentrations in human sweat, serum and juice were analyzed by amperometric method, and the recoveries ranged from 97.00 to 109.00% (RSD ≤ 5.00%). In addition, the CuNW/RGO/CF sensor exhibits excellent anti-interference ability and stability, maintaining 93% of its original sensitivity for 25 days. This facile and cost-effective method provides a new strategy for detecting glucose in organisms and food. [ABSTRACT FROM AUTHOR]

[Display omitted] Direct ethanol fuel cell (DEFC) has the advantages of high power density, high energy conversion efficiency and environmental friendliness, but its commercialization is restricted by factors such as insufficient activity and low anti-poisoning ability of anode catalyst for incomplete oxidation of ethanol. It is of great significance to design and prepare anode catalyst with high activity and high anti-poisoning ability that can be recycled. In this work, tubular palladium-based (Pd-based) catalysts with abundant lattice defect sites were prepared by simple and reproducible electro-displacement reactions using Cu nanowires as sacrificial template. Pd is the main catalytic element which provides adsorption sites for ethanol oxidation. Ag and Cu introduced facilitates the formation of hydroxyl groups to oxidize toxicity intermediates, and changes the d-band center position of Pd, so as to adjust the adsorption and desorption of ethanol and its intermediates on the Pd surface. At the same time, Au introduced with high potential maintains the stability of the catalyst structure. The tubular structure exposes more active sites, improves the atomic utilization rate and enhances the ability of the catalyst resisting dissolution and aggregation. The series of PdAuAgCu tubular catalysts with outer layer dendrites were prepared by electro-displacement reactions using the mixture (ethylene glycol : ultra-pure water = 3 : 1) as the reaction solvent and fivefold twinned Cu nanowires as sacrificial template. The performance evaluation of ethanol electrocatalytic oxidation showed that the Pd 17 Au 40 Ag 11 Cu 32 tubular catalysts were prepared at 120 °C and 10 mM CTAB had excellent overall performance, with a peak mass activity of 6335 mA mg Pd -1 , which was 9.6 times of Pd/C (JM). The residual current density after the stability test of 3000 s was 249 mA mg Pd -1 , which was 3.3 times of Pd/C (JM). [ABSTRACT FROM AUTHOR]

The localized surface plasmon resonance (LSPR) of metal nanomaterials has unique optoelectronic properties, and the research on improving the photovoltaic performance of thin-film solar cells based on the LSPR effect has become one of the hot research fields of widespread concern at home and abroad. In this paper, ultrathin copper nanowires of face-centered cubic structure with a diameter of about 20 nm was synthesized by a low-temperature hydrothermal reduction method using glucose as reducing agent, copper chloride dihydrate as copper source, and hexadecylamine and octadecylamine as capping agents. The crystal structure, morphology and optical properties of the synthesized products were characterized by X-ray diffraction (XRD), ultraviolet-visible absorption spectroscopy (UV-Vis) and scanning electron microscopy (SEM). In addition, copper nanowires and nanoparticles were mixed as electron transport layers to utilize their LSPR effect to improve the light harvesting efficiency and electron transport efficiency of perovskite solar cells (PSCs), and the influence of the indoor photovoltaic performance of PSCs was investigated. The research shows that, compared with the device without Cu NWs, the energy conversion efficiency (PCE) of PSCs with Cu NWs under simulated sunlight with the light intensity of 100 mW/cm² increases from 18.46% to 20.47%; The PCE under the indoor LED light source of 2 000 lux has been greatly increased from the original 27.8% to 35.2%, and the indoor photovoltaic efficiency has been improved by as much as 26.6%. [ABSTRACT FROM AUTHOR]

Abstract Electroreduction of carbon dioxide into fuels and feedstocks with renewable energy is an attractive route to mitigate carbon emission and solve energy crisis. However, how to improve the selectivity of high‐value multicarbon products is still challenging. Here, we demonstrate that the high‐index crystalline surface of copper could be designed and obtained through a simple square‐wave potential treatment on copper nanowires, which is beneficial to improve the selectivity of multi‐carbon products, especially the reaction route towards ethylene. The Faradaic efficiency of C2+ products can reach nearly 60%, and hydrogen can be suppressed to below 20%. Density functional theory (DFT) calculations reveal that (311) high‐index facet can activate CO2 effectively and promote adsorption of the *COCOH intermediate on copper for ethylene formation, therefore improves the selectivity of ethylene and inhibits the competing hydrogen evolution reaction. This method can be extended to the design of other catalytic systems and has inspirations for other electrochemical catalytic reactions.

• Robust Cu@Ag core–shell nanowires have been synthesized. • The Ag coating is tailored via a facile galvanic replacement method. • The strain sensor is used to detect hand gestures and communicate with Morse code. • Enhanced thermal stability and reliable antibacterial activity are demonstrated. Copper nanowires (CuNWs) have shown great potential as transparent electrodes for cost-effective wearable electronics. However, its unsatisfactory electrical conductivity and intrinsic susceptibility to oxidation hinder practical applications. To address these issues, herein, ultra-stable Cu@Ag core–shell NWs have been designed via a facile galvanic replacement method for wearable applications. The thermal stability of the NWs is significantly enhanced after introducing Ag, and superior stability is achieved with a more uniform Ag coating. The structural integrity of the percolation networks is basically maintained after 5 days' annealing treatment at a high temperature (≥150 °C). The devices based on core–shell NWs show reliable heating performance, and can further be used for defrosting and heating water/ice applications. Owing to optimized contact between Ag-coated NWs, the devices exhibit excellent mechanical performance under repetitive bending. Based on above structural design, the resultant strain sensors show high sensitivity, good repeatability and a wide sensing range, which are capable to detect various hand gestures and communicate with Morse code. Furthermore, the fabricated core–shell NWs show robust antibacterial activity, which is essential for wearable healthcare applications, outperforming that of pristine CuNWs. This work provides a promising way for the design of high-performance metal NWs for advanced wearable electronics. [ABSTRACT FROM AUTHOR]

• A hybrid nanoparticle Ba 0.7 Sr 0.3 TiO 3 (BST) anchored on Copper Nanowire (CuNW) was synthesized using a facile co-precipitation followed by hydrothermal method. • The findings indicate that nanocomposites incorporating BST@CuNW hybrids exhibited enhanced dielectric loss and more pronounced microwave power absorption compared to samples with equivalent CuNW and/or BST loadings. • A composite sample measuring one-millimeter-thick, containing 10:15 (wt/wt) CuNW: BST hybrid nanoparticles with a density of 1.49 g/cc, attenuated 99.1 % of incident microwave power and demonstrated a shielding effectiveness of 21.2 dB in the X-band. In this work, hybrid epoxy nanocomposites containing varying loading of copper nanowires (CuNW), Ba 0.7 Sr 0.3 TiO 3 (BST), and BST@CuNW hybrid nanoparticles were prepared and analyzed for their microwave absorption characteristics. The nanoparticles used in this study were prepared using a facile co-precipitation and hydrothermal methodology. The synthesized nanoparticles were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD) for their morphology and phase determination. While the XRD results confirmed the presence of BST and CuNW, the SEM micrographs obtained on the hybrid BST@CuNW nanoparticles show BST anchored on the CuNW surfaces. A series of epoxy composites containing varying loading of synthesized nanoparticles were prepared and characterized for their microwave properties, such as complex permittivity, shielding effectiveness, and power coefficients. The results indicate that nanocomposites containing BST@CuNW hybrids exhibited enhanced dielectric loss and more significant microwave power absorption compared to samples with equivalent CuNW and/or BST loading. The best composite sample, i.e., a one-millimeter-thick epoxy containing 10:15 (wt/wt) CuNW: BST hybrid nanoparticles with an estimated density of 1.49 g/cc attenuated 99.1 % of incident microwave power and exhibited a shielding effectiveness value of 21.2 dB in the X-band (8–12 GHz) of the microwave frequency spectrum. These lightweight polymer composites with high microwave absorption in the X-band are useful for military and civilian applications. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of carbon dioxide is an attractive and challenging strategy to solve the problems of renewable energy storage and carbon neutral. However, activity, selectivity, and stability of present developing catalysts for production of C2H4 are not as high as required for practical applications. Herein, we report dezincified copper nanowires (pre-CuZn-CuNW) derived from an electrodeposited CuZn alloy by a wet chemical method for electrochemical reduction of carbon dioxide to C2H4. Compared with pre-Cu-CuNW (the copper nanowires derived from a bulk Cu), the pre-CuZn-CuNW significantly enhances the catalytic activity and the selectivity for C2H4. The partial normalized current density of the pre-CuZn-CuNW for production of C2H4 increases to 183 mA∙cm−2, which is about twice relative to pre-Cu-CuNW. The faradaic efficiency (FE) of the pre-CuZn-CuNW for C2H4 can be maintained over 46% for 24 h during carbon dioxide reduction reaction. The improved catalytic performance can be attributed to the formation of a special nanowire structure with larger electrochemical active surface area and higher intrinsic activity of the pre-CuZn-CuNW during the dealloying process. [ABSTRACT FROM AUTHOR]

Nowadays, the advancement of thermoconductive electromagnetic interference (EMI) shielding materials for the next generation of electronics is in high demand. We present, in this research, the fabrication of the highly thermoconductive nanopapers based on aramid nanofiber (ANF) and ultralong copper nanowires (ULCuNWs) with outstanding EMI shielding effectiveness (SE) and mechanical properties. A homogeneous red brick color nanopaper (thickness 40–50 μm) was fabricated by homogenizing a mixture of the ULCuNWs (10–40 wt %) in the ANF suspension, then vacuum filtration, and drying. The morphology of the nanopapers reveals that the ULCuNWs were uniformly dispersed and interweaved with ANF to form two-dimensional (2D) layers in the nanopapers. With the increase in the ULCuNWs content, the nanopaper shows outstanding mechanical properties and reaches the optimal tensile strength (σ) of 228 MPa and Young's modulus of 6.12 GPa at the filler content of 30 wt %. Moreover, the variation of the in-plane thermal conductivity (λ//) and EMI SE of the nanopapers strongly depends on the amount of the ULCuNWs; the ULCuNWs30/ANF nanopapers obtain a notable λ// and EMI SE of around 8.25 W·m–1·K1 and 54.7 dB, respectively, with the mass content of 30 wt % at ambient conditions. The thermal treatment of the ULCuNWs30/ANF nanopapers at 180 °C increases the λ// and EMI SE by 60% and 9%, respectively. The ULCuNWs30/ANF nanopaper demonstrates an impressive heat dissipating capability. In addition, the ULCuNWs/ANF nanopapers show eminent thermal stability up to 500 °C and flame retardancy with an extremely low total heat release of 0.72 kJ·g–1. Therefore, ULCuNWs/ANF nanopapers can be considered great potential materials alternative to the current thermoconductive materials for heat dissipating applications in modern electronics. [ABSTRACT FROM AUTHOR]

Polypropylene (PP), a promising engineering thermoplastic, possesses the advantages of light weight, chemical resistance, and flexible processability, yet preserving insulative properties. For the rising demand for cost-effective electronic devices and system hardware protections, these applications require the proper conductive properties of PP, which can be easily modified. This study investigates the thermal and electrical properties of isotactic polypropylene/copper nanowires (i-PP/CuNWs). The CuNWs were harvested by chemical reduction of CuCl2 using a reducing agent of glucose, capping agent of hexadecylamine (HDA), and surfactant of PEG-7 glyceryl cocoate. Their morphology, light absorbance, and solution homogeneity were investigated by SEM, UV-visible spectrophotometry, and optical microscopy. The averaged diameters and the length of the CuNWs were 66.4 ± 16.1 nm and 32.4 ± 11.8 µm, respectively. The estimated aspect ratio (L/D, length-to-diameter) was 488 ± 215 which can be recognized as 1-D nanomaterials. Conductive i-PP/CuNWs composites were prepared by solution blending using p-xylene, then melt blending. The thermal analysis and morphology of CuNWs were characterized by DSC, polarized optical microscopy (POM), and SEM, respectively. The melting temperature decreased, but the crystallization temperature increasing of i-PP/CuNWs composites were observed when increasing the content of CuNWs by the melt blending process. The WAXD data reveal the coexistence of Cu2O and Cu in melt-blended i-PP/CuNWs composites. The fit of the electrical volume resistivity (ρ) with the modified power law equation: ρ = ρo (V − Vc)−t based on the percolation theory was used to find the percolation concentration. A low percolation threshold value of 0.237 vol% and high critical exponent t of 2.96 for i-PP/CuNWs composites were obtained. The volume resistivity for i-PP/CuNWs composite was 1.57 × 107 Ω-cm at 1 vol% of CuNWs as a potential candidate for future conductive materials. [ABSTRACT FROM AUTHOR]

The overuse of copper-based fertilizers and pesticides over the last few decades has resulted in detrimental risks to our environment. Nano-enabled agrichemicals with a high effective utilization ratio have shown great potential for maintaining or minimizing environmental issues in agriculture. Copper-based nanomaterials (Cu-based NMs) serve as a promising alternative to fungicides. Three types of Cu-based NMs with different morphologies were analyzed for their different antifungal effects on Alternaria alternata in this current study. Compared to commercial copper hydroxide water power (Cu(OH)2 WP), all tested Cu-based NMs, including cuprous oxide nanoparticles (Cu2O NPs), copper nanorods (Cu NRs) and copper nanowires (Cu NWs), especially Cu2O NPs and Cu NWs, showed higher antifungal activity against Alternaria alternata. Its EC50 were 104.24 and 89.40 mg L−1, respectively, achieving comparable activity using a dose approximately 1.6 and 1.9-fold lower. Cu-based NMs could introduce the downregulation of melanin production and soluble protein content. In contrast to trends in antifungal activity, Cu2O NPs showed the strongest power in regulating melanin production and protein content and similarly exhibited the highest acute toxicity to adult zebrafish compared to other Cu-based NMs. These results demonstrate that Cu-based NMs could offer great potential in plant disease management strategies.

The electrochemical nitrate reduction reaction (NITRR) provides a promising solution for restoring the imbalance in the global nitrogen cycle while enabling a sustainable and decentralized route to source ammonia. Here, we demonstrate a novel electrocatalyst for NITRR consisting of Rh clusters and single‐atoms dispersed onto Cu nanowires (NWs), which delivers a partial current density of 162 mA cm−2 for NH3 production and a Faradaic efficiency (FE) of 93 % at −0.2 V vs. RHE. The highest ammonia yield rate reached a record value of 1.27 mmol h−1 cm−2. Detailed investigations by electron paramagnetic resonance, in situ infrared spectroscopy, differential electrochemical mass spectrometry and density functional theory modeling suggest that the high activity originates from the synergistic catalytic cooperation between Rh and Cu sites, whereby adsorbed hydrogen on Rh site transfers to vicinal *NO intermediate species adsorbed on Cu promoting the hydrogenation and ammonia formation. [ABSTRACT FROM AUTHOR]

As strong and shape‐conformable as biological muscles, nitinol shape memory alloys (SMAs) artificial muscles have great merit when applied for bio‐inspired robots. However, the low bandwidth and slow actuation speed of SMAs due to their sluggish cooling have long been troublesome, limiting possible applications. Here, to expedite the cooling rate, a Cu nanowire forest is directly grown on the surfaces of 3D shaped SMA coil (SMAc) to increase the surface area by 15 times and boost thermal convection. As a result, the Cu nanowire forest grown SMA coil (CuNF‐SMAc) shows accelerated cooling compared to bare SMAc (B‐SMAc): the actuation speed of CuNF‐SMAc is 100% faster than that of bare SMAc (B‐SMAc) under natural cooling and 170% faster under forced‐air cooling. With this faster actuation, CuNF‐SMAc artificial muscles are employed in a versatile prosthetic hand to bend and flex fingers. The proposed prosthetic hand successfully demonstrates a series of sign language within 4 s for each letter, and rhythmically plays a grand piano. Moreover, unique retractable feline claws are mimicked which demonstrate a fully tunable frictional force just like how cats do it, expanding the potential of a cooling‐accelerated SMAc artificial muscle. [ABSTRACT FROM AUTHOR]

Electrochemical application has been widely used in the study of biosensors. Small biomolecules need a sensitive sensor, as the transducer that can relay the signal produced by biomolecule interactions. Therefore, we are improvising a sensor electrode to enhance electrochemical conductivity for the detection of small DNA molecule interaction. This work describes the enhanced electrochemical conductivity studies of copper nanowires/gold nanoparticles (CuNWs/AuNPs), using the screen-printed gold electrode (SPGE). The AuNPs were synthesized using the Turkevich method as well as characterized by the high-resolution transmission electron microscopy (HRTEM) and ultraviolet-visible (UV-Vis) analysis for the particle size and absorption nature, respectively. Further, the surface morphology and elemental analysis of a series of combinations of different ratios of CuNWs-AuNPs-modified SPGE were analyzed by field emission scanning electron microscopy (FESEM) combined with an energy dispersive X-ray (EDX). The results indicate that the nanocomposites of CuNWs-AuNPs have been randomly distributed and compacted on the surface of SPGE, with AuNPs filling the pores of CuNWs, thereby enhancing its electrochemical conductivity. The cyclic voltammetry (CV) method was used for the evaluation of SPGE performance, while the characterization of the electrochemical conductivity of the electrode modified with various concentrations of AuNPs, CuNWs, and different volumes of dithiopropionic acid (DTPA) has been conducted. Of the various parameters tested, the SPGE modified with a mixture of 5 mg/mL CuNWs and 0.25 mM AuNPs exhibited an efficient electrochemical conductivity of 20.3 µA. The effective surface area for the CuNWs-AuNPs-modified SPGE was enhanced by 2.3-fold compared with the unmodified SPGE, thereby conforming the presence of a large active biomolecule interaction area and enhanced electrochemical activity on the electrode surface, thus make it promising for biosensor application. [ABSTRACT FROM AUTHOR]

In this work, we explore the effect of increasing electrodeposition time on the dielectric properties of Cu/AAO nanocomposites. Cu nanowires are electrodeposited within the AAO template pores fabricated using a two-step anodization process. The morphology, composition, and crystalline structure are characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The dielectric properties, including the real part and the imaginary part of the effective complex relative permittivity and the effective AC conductivity of the AAO template and Cu/AAO nanocomposites, are subsequently analyzed. The results demonstrate a clear improvement in effective permittivity and effective AC conductivity of Cu/AAO nanocomposites with increasing electrodeposition time, indicating the potential for tailoring the dielectric properties of AAO templates through the incorporation of metal nanowires for advanced capacitor applications. • The AAO templates are fabricated by two-step anodization process. • Copper nanowires are electrodeposited within AAO template. • Samples are characterized using SEM, EDX, and XRD. • The AAO Template-Copper nanowires exhibits a higher dielectric function. • The AAO Template-Copper nanowires has higher AC conductivity. [ABSTRACT FROM AUTHOR]

It is of great significance to explore a low cost and high sensitivity sialic acid (SA) detection method for early diagnosis and prognosis of cancer. Electrochemiluminescence (ECL) has aroused many scholars' interest in the accurate analysis of multi-domain analytes for its excellent performance. In order to improve the ECL signal strength and the corresponding detection sensitivity, it is effective to develop new ECL reagents. Copper nanowires (CuNWs) as luminophor has always been a blank in the field of ECL sensors. In this study, a glycosyl imprinted electrochemiluminescence sensor (GIP-ECLS) for SA specificity detection in serum was developed using CuNWs as luminophor. CuNWs can not only form quasi-three-dimensional (3D) conductive network, but also realize self-enhancement of ECL signal through Cu2+ and Cu+ conversion. In addition, the excellent conductivity and wrapping properties of Ti 3 C 2 provide a large electroactive area for electrode modification. More importantly, 3-aminobenzenoboric acid (3-ABA) specifically binds to SA to form B-N or B-O, which lays the foundation for selective recognition of SA. Under optimal conditions, the signal response of GIP-ECLS showed a good linear relationship with SA concentration at 5 × 10−12–1 × 10−8 mol L−1 (R 2 = 0.997), and the limit of detection (LOD) was 1.17× 10−12 mol L−1. The results showed that in the actual sample analysis, the recovery rate of SA detected by GIP/Ti 3 C 2 /CuNWs/GCE was good, and it had good selectivity and stability, which provided ideas for designing minimally invasive and highly sensitive detection of SA in serum samples. [Display omitted] • An ECL sensor system with high selectivity was constructed for the detection of SA. • CuNWs has been reported for the first time to achieve self-enhancing ECL signals. • Ti 3 C 2 provided an effective specific surface area for the loading of CuNWs. • Glycosyl imprinting based on borate bond improved the selective detection of SA. [ABSTRACT FROM AUTHOR]

The use of electrochemical method to remove nitrate and reduce it to ammonia under mild conditions has attracted widespread attention. In this study, a dendritic structured electrode composed of polyaniline (PANI) modified copper nanowires was designed and synthesized on copper foam (CF) as the electrocatalytic nitrate (NO 3 -) reduction reaction (NO 3 -RR) catalyst. The PANI can not only accelerate the migration of electron, but also provide abundant active sites. The optimized sample exhibited an attractive electrocatalytic ability for NO 3 - reduction to NH 3 with conversion rate, faradaic efficiency, and selectivity of 95.1%, 96.1%, and 98.38%, respectively, at −0.89 V vs reversible hydrogen electrode (RHE). This work provides an efficient and convenient solution for solving nitrate pollution and achieving nitrogen cycling. [Display omitted] • A facile electrodeposition method was developed to synthesize dendritic electrode. • The dendritic arrays of PANI on the B-Cu nanowire can provide multi-active site. • The optimized ED-30 exhibits brilliant nitrate reduction ability at −0.89 V vs RHE. [ABSTRACT FROM AUTHOR]

In this work epoxy nanocomposites containing varying content of copper nanowires (CuNW) were produced. The CuNW were synthesized using a facile one‐pot hydrothermal synthesis method. The composites were characterized for their electrical conductivity and electromagnetic interference (EMI) shielding effectiveness in the X‐band. The electrical conductivity of the epoxy composites was measured, and the composites containing 12 wt % CuNW demonstrated percolated behavior and exhibited a frequency‐independent conductivity value of 1.76 × 10−6 S m−1 in the range of 25–200 Hz. The 12 wt % CuNW sample demonstrated an EMI shielding effectiveness value of 6.5 dB, which corresponds to 77.1 % attenuation of the incident electromagnetic wave. Furthermore, an absorption‐dominated shielding mechanism was observed in these composites. [ABSTRACT FROM AUTHOR]

Electroreduction of carbon dioxide into fuels and feedstocks with renewable energy is an attractive route to mitigate carbon emission and solve energy crisis. However, how to improve the selectivity of high‐value multicarbon products is still challenging. Here, we demonstrate that the high‐index crystalline surface of copper could be designed and obtained through a simple square‐wave potential treatment on copper nanowires, which is beneficial to improve the selectivity of multi‐carbon products, especially the reaction route towards ethylene. The Faradaic efficiency of C2+ products can reach nearly 60%, and hydrogen can be suppressed to below 20%. Density functional theory (DFT) calculations reveal that (311) high‐index facet can activate CO2 effectively and promote adsorption of the *COCOH intermediate on copper for ethylene formation, therefore improves the selectivity of ethylene and inhibits the competing hydrogen evolution reaction. This method can be extended to the design of other catalytic systems and has inspirations for other electrochemical catalytic reactions. [ABSTRACT FROM AUTHOR]

Soft actuators with high flexibility have received widespread attention. Here, a transparent electrothermal soft actuator is designed and manufactured via sandwiched copper nanowires (Cu NWs) between two kinds of flexible substrates with different thermal expansion characteristics (polyethylene-terephthalate (PET) and low-density polyethylene (LDPE)). In order to improve bending characteristics of the soft actuator, heating performance of heaters with different widths is studied, and the bending characteristics of strain gauges under different voltages are also studied. The fabricated soft actuator can produce a bend of 90° and provide about 1 mN of force at a low voltage of 6 V. The application of this type of soft actuator is demonstrated toward biomimetic robotics, a two-finger flexible transparent gripper is designed, where two soft actuators are utilized to simulate the movements of human fingers and realizes the operation of picking and placing fine objects. In addition, the topography of the object can be feasibly observed during clamping process of the soft actuator with certain light transmittance, which is favorable for the soft gripper application. [ABSTRACT FROM AUTHOR]

Co–B has good catalytic activity in the hydrogenation reaction of unsaturated groups and has been widely studied and applied. Co–B catalysts were usually prepared by reducing cobalt salts with reducing agents. However, the high surface energy and magnetic properties of Co–B catalysts made the particles easily agglomerate. Then, agglomeration increased the particle size of the sample and reduced the effective surface area of the catalyst powder, which limited the catalytic activity of the Co–B catalysts. A new type of Co–B/copper nanowires/cetyl trimethyl ammonium bromide (Co–B/CuNWs/CTAB) catalyst with high catalytic activity was prepared by a chemical reduction in this work. The performance of Co–B/CuNWs/CTAB was studied in the hydrolysis of ammonia-borane (AB) and CuNWs inserted into the Co–B interlayer could avoid particle agglomeration, thereby effectively increasing the specific surface areas of the catalysts. Furthermore, the insertion of CuNWs facilitated the transportation of electrons and improved catalytic activity. The BET analysis shows that the maximum surface area of the sample is 148.9 m2/g. Meanwhile, the hydrogen generation rate of 13.46 L min−1·g−1 at 30 °C was obtained by using the synthesized Co–B/CuNWs/CTAB catalyst with a low activation energy of 8.771 kJ mol−1. [Display omitted] • Co–B/CuNWs/CTAB catalyst with high catalytic activity was prepared. • CuNWs inserted into the Co–B interlayer could avoid particle agglomeration. • CuNWs facilitated the transportation of electrons and improved catalytic activity. • CTAB controlled the morphology of catalyst. [ABSTRACT FROM AUTHOR]

Copper nanowires (Cu NWs) are considered an excellent alternative to indium tin oxide (ITO) in flexible transparency electrodes (FTEs). However, the mixed particles and surface oxidation of Cu NWs degrade the transmittance and conductivity of the electrodes. Therefore, highly purified Cu NWs without oxidation are vital for high-performance FTEs. Herein, a facile and effective purification process is introduced to purify Cu NWs in a water and n-hexane system, which takes advantage of the differences in hydrophilicity between Cu NWs and Cu NPs caused by their different adsorption affinities to octadecylamine (ODA). At the same sheet resistance, the transmittance of the purified Cu NW-based FTEs improved approximately 2% compared to that of non-purified Cu NW-based FTEs. Immersion of the electrode in glacial acetic acid removed the surface organics and oxides. After only 40 s of treatment, the sheet resistance dramatically decreased from 105 Ohm/sq to 31 Ohm/sq with a transmittance of 85%. In addition, the Cu NW-based FTE conductors showed excellent flexibility (remaining stable after 1000 bending cycles). The Cu NW-based FTEs were further applied to fabricate a flexible transparent heater. At a voltage of 10 V, the temperature of the heater reached 73 °C, demonstrating the potential applications of this material in various fields.

The development of highly efficient and stable electrocatalysts for their application in electrochemical detection is desirable. Herein, a new copper nanowires (CuNWs) modified electrode was fabricated by coating poly(dimethyl diallyl ammonium chloride) (PDDA) stabilized CuNWs composite onto the the glassy carbon electrode (GCE), and used for electro-catalyze and determination of cysteine (CySH). The morphology, structure, and surface property of fabricated CuNWs were tested using SEM, XRD, and XPS, separately. Electrocatalytic behavior of the modified electrode (CuNWs-PDDA/GCE) for CySH oxidation in alkaline medium was researched by cyclic voltammetry (CV) and chronoamperometry (CA) thoroughly, displaying excellent electrocatalytic oxidation activity and sensing ability towards CySH with a rapid and sensitive anodic current response at low oxidation potential. In the amperometric detection of CySH, the as-prepared electrode displayed a significantly wide linear range from 2 μM to 260 μM and a detection limit of 0.19 μM with a sensitivity of 1.430 μAμM−1cm−2. The proposed CySH sensor exhibited good reproducibility, stability, and anti-interference ability, and has been used to detect CySH in human plasma samples successfully with good applicability.

The mechanical properties of copper (Cu) nanowires (NWs) wrapped by carbon nanotube (CNT) under compression are studied by molecular dynamics simulations. By constructing a new structural model, which contains a Cu NW and a CNT that is denoted as CNT@Cu, the mechanical properties, deformation process and structural transformation are investigated in terms of stress–strain relationship, number of stacking faults (SFs) and dislocations, average bond length and atomic configurations. Results show that stress–strain exhibits two nonlinear elastic contraction stages and two intervening stages of inelastic deformation. The stress of Cu NW is almost not affected by the generation and migration activities of SFs but strongly depends on the increasing ratio of SFs due to the supporting of CNT. The inelastic plastic deformation is initiated by nucleation of partial dislocations on the {110} surface and then propagates to interior along the {111} close-packed planes. Wrapped by CNT, a unique structural transformation of compressed Cu NW is found, which is from < 100 > /{111} to < 100 > /{100} through the annihilation of {111} SFs planes and formation of {100} SFs planes along the [100] crystallographic orientations. The < 100 > /{100}-structured wire would undergo nonlinear elastic contraction until to a certain large strain, and then bend near the middle part before NW fractures eventually at a very high stain. What's more, the < 100 > /{100}-structured Cu NW possess high reversibility under unloading and an interestingly structural reverse transformation from < 100 > /{100} to < 100 > /{111} structure is observed prior to the fracture of NW at a high strain for the CNT@Cu model due the support of CNT. The ultimate compressive elastic strength of {100} (UCES-{100}) and ultimate elastic stain will decrease as the temperature increases from 10 to 500 K. The UCES of pristine (UCES-pristine) and UCSE-{100} decrease as diameter decreases. [ABSTRACT FROM AUTHOR]

Transparent electrodes are essential elements of devices bearing a screen or display, as well as solar cells, LEDs etc. To overcome the drawbacks presented by indium tin oxide, nanomaterials have been proposed for a long time as alternatives. Metal nanowires are particularly interesting for their high intrinsic electrical conductivity. Copper nanowires have attracted wide interest due to the low cost and high abundancy of the starting material. However, they are easily oxidized thus suitable strategies must be devised to prevent it. This review discusses the fundamental properties and challenges of copper nanowires, focusing on the efforts made to make them longer and thinner then the strategies to prevent oxidation and to join them in the network are presented. After that, mechanical properties are summarized and applications are presented, before conclusions and perspectives are finally given. [ABSTRACT FROM AUTHOR]

Polypropylene (PP), a promising engineering thermoplastic, possesses the advantages of light weight, chemical resistance, and flexible processability, yet preserving insulative properties. For the rising demand for cost-effective electronic devices and system hardware protections, these applications require the proper conductive properties of PP, which can be easily modified. This study investigates the thermal and electrical properties of isotactic polypropylene/copper nanowires (i-PP/CuNWs). The CuNWs were harvested by chemical reduction of CuCl2 using a reducing agent of glucose, capping agent of hexadecylamine (HDA), and surfactant of PEG-7 glyceryl cocoate. Their morphology, light absorbance, and solution homogeneity were investigated by SEM, UV-visible spectrophotometry, and optical microscopy. The averaged diameters and the length of the CuNWs were 66.4 ± 16.1 nm and 32.4 ± 11.8 µm, respectively. The estimated aspect ratio (L/D, length-to-diameter) was 488 ± 215 which can be recognized as 1-D nanomaterials. Conductive i-PP/CuNWs composites were prepared by solution blending using p-xylene, then melt blending. The thermal analysis and morphology of CuNWs were characterized by DSC, polarized optical microscopy (POM), and SEM, respectively. The melting temperature decreased, but the crystallization temperature increasing of i-PP/CuNWs composites were observed when increasing the content of CuNWs by the melt blending process. The WAXD data reveal the coexistence of Cu2O and Cu in melt-blended i-PP/CuNWs composites. The fit of the electrical volume resistivity (ρ) with the modified power law equation: ρ = ρo (V − Vc)−t based on the percolation theory was used to find the percolation concentration. A low percolation threshold value of 0.237 vol% and high critical exponent t of 2.96 for i-PP/CuNWs composites were obtained. The volume resistivity for i-PP/CuNWs composite was 1.57 × 107 Ω-cm at 1 vol% of CuNWs as a potential candidate for future conductive materials.

In this study, metallic copper (Cu) nanowires are synthesized by reducing thermally synthesized CuO nanowires under an indigenously developed hydrogen plasma system. The X-ray diffraction (XRD) results of the plasma-synthesized nanowires indicate the presence of metallic copper [(111) and (200)] and the field emission scanning electron microscopy (FESEM) further affirms the findings by presenting a stark difference in contrast of the nanowires before and after plasma treatment with diameters of 50 and 100 nm, respectively. The nanowires are studied for hydrogen evolution reaction in a neutral medium and they show excellent performance than the previously reported studies on bulk copper, with an overpotential of 210 mV at a current density of 10 mA/cm2 and an exchange current density of 60 exp-5 A/cm2 which is an order of magnitude larger than the reported values on bulk copper. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy indicates that the surface of the nanowires is highly rich in metallic copper resulting in better electrochemical performance of the metallic Cu nanowires in a neutral environment. • DBD plasma technique is used for the synthesis of Copper nanowires. • Metallic Copper nanowires are successfully tested for HER. • Exchange current density of up to 60exp-5 A/cm2 is observed. • Overpotential requirements attain 210 mV to reach 10 mA/cm2. [ABSTRACT FROM AUTHOR]

Copper nanowires (CuNWs) have been attracting a lot of attention as an alternative to silver nanowires for next generation transparent conductors because of their favorable electric conductivity, mechanical properties, abundance, and low cost. Here, we report a new route using copper hydroxide as precursor, diethylenetriamine as complexing agent, and glucose as reducing agent, by which CuNWs can be acquired within a short reaction time of 10 min and a mild temperature of around 80℃. The effect of reaction temperature, copper precursor concentration, and glucose concentration on the morphology and dimensions of the synthesized CuNWs were investigated. CuNWs of 37 nm in diameter and 17 µm in length were incorporated in an ethylene vinyl acetate (EVA)-coated transparent conductive film, which offered a relative visible light transmission of 91% and a sheet resistance of 48 Ω/sq. [ABSTRACT FROM AUTHOR]

Determination of Cu(II) plays a critical role to prevent over dosage of Cu(II) that exceed cellular needs in drinking water. Rare sensors based on localized surface plasmon resonance (LSPR) are used to determinate the trace of metal ions. In this work, a process of LSPR sensor is developed to determinate Cu(II) with LSPR. A trench array was fabricated via photolithography to wet the bottoms of trenches using oxygen plasma. Hydrophobic halogen-terminated silane, a water immiscible compound before hydrolysis, was evaporated for deposition on the plasma-treated trench template surface. The silane compound was hydrolyzed along the edges of two sides of the trench bottom to form a dual-stripe of an initiator. Polyacrylonitrile (PAN) was grafted from the dual-stripe of the initiator to covert to polyvinyltetrazole (PVT) dual-stripes via a cyano-to-tetrazole reaction, which could chelate Cu(II) at various concentrations. a The Cu(II) ions within the PVT dual-stripes were reduced to form a PVT–copper hybrid dual-stripe nanowires (PCDW) array, resulting in a geometrical change from a dual-stripe to a two-humped structure as the Cu(II) was chelated by the PVT dual-stripes after the in-situ reduction. The reflectance spectra could be used to analyze the position of the extinction wavelength and the peak shape of PCDW array. The linear range between the wavelength shift and Cu(II) concentration from 10 to 1280 nM was established to obtain the detection limit of ∼10 nM. Our proposed method provides a novel pathway to efficiently fabricate a dual-nanowire array with a scale of less than 100 nm, which demonstrates significant potential for highly sensitive and selective Cu(II) sensing. • Scalable dual-stripe arrays of ATRP were formed on a silicon substrate via semiconductor processes. • PAN dual-stripes were grafted from the dual-stripes of the initiator via ATRP as a precursor to convert to PVT dual-stripes. • Cu(II) ions were chelated by PVT dual-stripes to synthesize PVT–copper hybrid dual-stripe nanowires after in-situ reduction. • The reflectance peaks of the PCDW array shift linearly with increasing Cu(II) concentration. • The limit of detection of the platform reaches 10 nM Cu(II) with linear range from 10–1280 nM. [ABSTRACT FROM AUTHOR]

We conducted an investigation on a flexible random laser (RL) device featuring non-noble plasmonic enhancement and scattering. The RL device was created by integrating copper nanowires (Cu NWs) and laser dyes (rhodamine 6G, R6G) into an acrylamide (AM) hydrogel matrix. The substantial overlap between the plasmonic resonance of Cu NWs and the emission of R6G effectively mitigates the requirements for lasing generation. Furthermore, the robust scattering induced by the three-dimensional distribution of Cu NWs contributes to a reduction in the laser threshold. Notably, the unique properties of the AM hydrogel ensure that the laser device exhibits excellent tensile recovery performance. The RL device is capable of maintaining stable lasing performance even after 100 % tensile deformation. This flexible laser device offers the advantages of a straightforward fabrication process, low cost, and robust lasing characteristics, thus paving the way for their advanced application in the future. [Display omitted] • A flexible hydrogel-based random laser that utilizes the plasmonic enhancement effect of non-noble metals was developed. • The threshold of random laser is effectively reduced by the local surface plasmon resonance effect of copper nanowires. • The random laser can maintain stable and high-quality laser output even after 100 % tensile deformation. [ABSTRACT FROM AUTHOR]

• Amplified SPCEs: CuNWs/rGO enhance chlorpyrifos detection via AChE inhibition. • Detection range: 10–200 µg/L, LOD: 3.14 µg/L, LOQ: 12.5 µg/L for chlorpyrifos. • Versatile analysis: water, orange juice; high recoveries, no interference. An enzymatic electrochemical biosensor was built for the indirect detection of organophosphates (OPs), based on acetylcholinesterase inhibition. The biosensor was fabricated for enhanced performance on a screen-printed carbon electrode (SPCE), modified with copper nanowires (CuNWs) composited with reduced graphene oxide (rGO). The oxidation current was measured using the cyclic voltammogram (CV) method, as generated by the enzymatic interaction between acetylcholinesterase (AChE) and its substrate, acetylthiocholine (ATCh). The biosensing response is the reduction in signal caused by the inhibition of acetylcholinesterase in the presence of an organophosphate inhibitor. Benchmarking shows that the CuNWs/rGO nanocomposite enhanced the signal current considerably and decreased the oxidation potential for electrochemical detection of the OP chlorpyrifos, exhibiting a wide linear detection range from 10 µg/L–200 µg/L, with a limit of detection of 3.1 µg/L and limit of quantification of 12.5 µg/L. This sensor is useful for the analysis of chlorpyrifos in drinking water and orange juice, with high recovery rates and no interference effects. [ABSTRACT FROM AUTHOR]

SARS‐CoV‐2 and other respiratory viruses spread via aerosols generated by infected people. Face masks can limit transmission. However, widespread use of disposable masks consumes tremendous resources and generates waste. Here, a novel material for treating blown polypropylene filtration media used in medical‐grade masks to impart antimicrobial activity is reported. To produce thin copper@ZIF‐8 core‐shell nanowires (Cu@ZIF‐8 NWs), Cu NWs are stabilized using a pluronic F‐127 block copolymer, followed by growth of ZIF‐8 to obtain uniform core‐shell structures. The Cu@ZIF‐8 NWs are applied to filtration media by dip coating. Aerosol filtration efficiency decreases upon exposure to ethanol (solvent for dip‐coating), but increases with addition of Cu@ZIF‐8 NWs. Cu@ZIF‐8 NWs shows enhanced antibacterial activity, compared to Cu NWs or ZIF‐8 alone, against Streptococcus mutans and Escherichia coli. Antiviral activity against SARS‐CoV‐2 is assayed using virus‐infected Vero E6 cells, demonstrating 55% inhibition of virus replication after 48 h by 1 µg of Cu@ZIF‐8 NWs per well. Cu@ZIF‐8 NWs' cytotoxicity is tested against four cell lines, and their effect on inflammatory response in A549 cells is examined, demonstrating good biocompatibility. This low‐cost, scalable synthesis and straightforward deposition of Cu@ZIF‐8 NWs onto filter media has great potential to reduce disease transmission, resource consumption, and environmental impact of waste. [ABSTRACT FROM AUTHOR]

Copper nanowires and Cu-Ag nanowires have various potential applications, such as transparent conductive film, flexible electronics, and conductive filler. In this study, we developed a new green fabrication method for silver-coated copper nanowires using methylsulfonylmethane (DMSO2), which is an environmentally friendly chemical at the food-grade level, to replace toxic chemicals, including ammonia, in the silver coating process. Copper nanowires were synthesized under various reaction temperatures and concentrations of hydrazine (N2H4), ethylenediamine (EDA), sodium hydroxide (NaOH), and copper precursor. The reaction temperature higher than 70 °C caused the oxidation of copper products and evaporation of the sample solution. The optimal conditions to synthesize copper nanowires more than 18 µm in length and 25–45 nm in diameter were determined: 9 M of NaOH, 50 µL of EDA, 17 mM of CuCl2, 5.7 mM of N2H4, and 70 °C reaction temperature. Cu-Ag nanowires, which have about a 12 nm thick silver shell, were successfully fabricated at room temperature under 1 mM of silver nitrate (AgNO3) and 1 wt % of DMSO2. Synthesis conditions for copper and silver-coated copper nanowires have been optimized.

Copper nanostructures are promising catalysts for the electrochemical reduction of CO2 because of their unique ability to produce a large proportion of multi‐carbon products. Despite great progress, the selectivity and stability of such catalysts still need to be substantially improved. Here, we demonstrate that controlling the surface oxidation of Cu nanowires (CuNWs) can greatly improve their C2+ selectivity and stability. Specifically, we achieve a faradaic efficiency as high as 57.7 and 52.0 % for ethylene when the CuNWs are oxidized by the O2 from air and aqueous H2O2, respectively, and both of them show hydrogen selectivity below 12 %. The high yields of C2+ products can be mainly attributed to the increase in surface roughness and the generation of defects and cavities during the electrochemical reduction of the oxide layer. Our results also indicate that the formation of a relatively thick, smooth oxide sheath can improve the catalytic stability by mitigating the fragmentation issue. [ABSTRACT FROM AUTHOR]

To meet the requirement of clean and efficient energy storage system for practical applications, supercapacitors (SCs), which are promising candidates for the next‐generation energy storage devices, have received tremendous attention. Herein, a hybrid electrode consisting of copper nanowires (Cu NWs) and carbon nanotubes (CNTs) is prepared by simple vacuum‐filtration method. Both Cu NWs and CNTs have excellent conductivities, high aspect ratios, and large surface areas, in which the two kinds of materials are evenly dispersed and are entangled with each other. The electrochemical performance characterization of the Cu@CuO NWs/CNTs hybrid electrode shows high specific capacitance of 1.7 F cm−2 and excellent cycling characteristics of 97.4% after 5000 cycles. The hybrid electrode of Cu@CuO NWs/CNTs with one‐dimensional (1D) structure provides significant advantages in terms of electron/ion transport pathways. The SC devices with excellent electrochemical performance and stability clearly demonstrate their broad applications as low‐cost, high‐performance power supplies for electronic devices. [ABSTRACT FROM AUTHOR]

In spite of its excellent electrical, mechanical, and low‐cost characteristics, copper nanowire has fatal issues in the oxidation problem and the lack of biological compatibility, which occasionally outweighs its advantages and limits its usage as electronics or biodevice applications. In this study, a novel wet chemical synthesis method is developed for the oxidation‐free Cu–Au core–shell nanowire based on the prepared Cu nanowire with alkylamine‐mediated synthesis and ligand exchange. The synthesized Cu–Au core–shell nanowire exhibits improved electrical stability against thermal oxidation under the harsh environment of 80 °C and 80% relative humidity. Additionally, to substantiate suitability for the biomedical application, the enhanced chemical stability and biocompatibility are investigated by utilizing the artificial perspiration and the cell culture. As a proof‐of‐concept demonstration, high performance wearable electromyogram (EMG), electrocardiogram (ECG) sensors for electrophysiological monitoring with the Cu–Au core–shell nanowire electrode are demonstrated with superior oxidation‐resistance and biocompatibility even after the harsh environment test. The Cu–Au core–shell nanowire can provide promising, cost‐effective electrode materials for various wearable electronics applications. [ABSTRACT FROM AUTHOR]

A mode-locked nanosecond Erbium-doped fiber laser (EDFL) based on copper nanowires (CuNWs) saturable absorber (SA) is successfully demonstrated in this article. The CuNWs were prepared by dissolving the CuNWs solution in a polydimethylsiloxane (PDMS) host polymer. Through the doctor blade technique, a free-standing CuNWs-PDMS film was formed. Upon inserting the film in a laser cavity, nanosecond pulses with a stable mode-locking was observed past the threshold pump power of 104.62 mW. The laser operated at the center frequency of 1.86 MHz and wavelength of 1563.3 nm. At the maximum available pump power of 187.04 mW, the 173 ns mode-locked pulse train achieved the highest pulse energy of 9.14 nJ and the maximum average output power of 1.703 mW. These results vindicate the capacity of the CuNWs film SA in producing nanosecond mode-locked EDFL in the 1550 nm region.

The composites comprising vertically aligned network of copper nanowires (CuNWs) in the presence of cellulose nanofibers were fabricated by using the freeze‐templating method and the effect of aspect ratio (A/R) of CuNWs on the thermal conductivity of epoxy composites was investigated. The thermal conductivity of epoxy composites increased to 0.79 W m−1 K−1 at 1.12 vol% of high A/R CuNWs loading, corresponding to the thermal conductivity enhancement of 365% as compared to the pure epoxy. The thermal conductivity of vertically aligned higher A/R CuNWs/epoxy, which is 38.5% and 51.9% higher than those of the lower A/R CuNWs and the randomly aligned CuNWs, respectively. The application of the epoxy composites in heat dissipation was demonstrated by the temperature changes of composites on a hot plate with the increase of heating time. These results indicate that the thermally conductive composites in this study could be applied for thermal dissipating materials in electronic devices. [ABSTRACT FROM AUTHOR]

The effects of copper nanowires (Cu NWs) and ionic liquid (1-butyl-3-methylimidazolium perchlorate, in short [BMIM] [ClO4]) on the tribological properties of ionic liquid under external voltages were explored using friction tests in this paper. The results showed that the ionic liquid with 0.15 wt.% Cu NWs after 60 days exhibited better lubricating property at a low voltage of 0.5 V. The worn surfaces characterized by SEM and XPS illustrated that the existence of the Cu2O could increase wear of friction pairs when Cu particles were oxidized. How the different forms of copper affect the lubrication of ionic liquid under external voltages were further discussed. This work provides a new thought of using metal ions to improve the lubrication performance of ionic liquids under external voltages. [ABSTRACT FROM AUTHOR]

Controlling aspect ratio of copper (Cu) nanowire (NW) is a vital role to determine the conductivity at a high transmittance for the transparent conductive electrode application, but systemic studies on aspect ratio control of Cu NW have been still in early stages. Herein, we systemically explore the aspect ratio of Cu NW by varying solution process parameters including reaction time and the concentration of additives (Cu precursor, reducing agent, and capping agent). From optimized process parameters, we successfully synthesize Cu NWs showing the high aspect ratio of ~ 1570, which is relatively comparable than that of previous reports. We characterize the sheet resistance with different transmittances, and consequently achieve excellent sheet resistance of 46 Ω sq−1 at transmittance = 93%, similar to that of indium tin oxide-based electrodes. Obtained Cu NW films also show stable bending reliability with applying bending radius of 6.5 mm. Such remarkable performances are attributed to high aspect ratio of our Cu NWs, which lead to reduced junction resistance in films. [ABSTRACT FROM AUTHOR]