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This study investigates the structural effects on the cross-plane thermal conductivity of Li4Ti5O12-based anode active material. Three structures are investigated: a basic structure consisting of LiBr/LiCl/Li4Ti5O12, polyvinylidene difluoride, and Super P (sample #1); a structure without Li4Ti5O12 (sample #2); and a structure without LiBr/LiCl (sample #3). Despite its high porosity level (77%), sample #1 exhibits higher thermal conductivity than sample #3 (64% porosity) in both air and vacuum conditions, potentially due to the extra structural bonding provided by LiBr/LiCl. The observed difference in cross-plane thermal conductivity between air and vacuum conditions provides insights into the configuration of the anode's active material in the heat transfer direction. The lower limit corresponds to the parallel thermal circuit configuration of active material and air, which is the product of the sample's porosity and thermal conductivity of air. Our analysis suggests that in sample #2, the anode's active material and air inside the pores demonstrate a more serial configuration, while in sample #3, they exhibit a more parallel configuration in the heat transfer direction. However, the thermal conductivity difference observed for sample #1 falls below the theoretical lower bound indicating significant thermal radiation within the pores. Furthermore, the in-plane thermal conductivity is predominantly controlled by the copper foil. Sample #2 exhibits the lowest in-plane thermal conductivity. This is attributed to the severe oxidization of the copper foil by LiBr/LiCl, which is confirmed by structure characterization. [ABSTRACT FROM AUTHOR]

Pulsed-power-driven underwater electrical explosion of cylindrical or conical wire arrays produces supersonic water jets that emerge from a bath, propagating through the air above it. Interaction of these jets with solid targets may represent a new platform for attaining materials at high pressure (>1010 Pa) conditions in a university-scale laboratory. However, measurements of the internal structure of such jets and how they interact with targets are difficult optically due to large densities and density contrasts involved. We utilized multi-frame x-ray radiographic imaging capabilities of the ID19 beamline at the European Synchrotron Radiation Facility to explore the water jet and its interaction with a 50 μm thick copper foil placed a few mm from the surface of water. The jet was generated with a ∼130 kA-amplitude current pulse of ∼450 ns rise time applied to a conical wire array. X-ray imaging revealed a droplet-type structure of the jet with an average density of <400 kg/m3 propagating with a velocity of ∼1400 m/s. Measurements of deformation and subsequent perforation of the target by the jet suggested pressures at the jet–target interface of ∼5 × 109 Pa. The results were compared to hydrodynamic simulations for better understanding of the jet parameters and their interaction with the foil target. These results can be used in future research to optimize the platform, and extend it to larger jet velocities in the case of higher driving currents supplied to the wire array. [ABSTRACT FROM AUTHOR]

Lithium foils were demonstrated to absorb surrogate protium for tritium-powered betavoltaics. 20 μ m thick lithium foils were hole-punched from a ribbon of electrodeposited lithium on copper foil. The lithium foils were loaded with hydrogen in a custom Sievert apparatus where the pressure drop showed full hydriding at a hydrogen pressure of 2 bar and at all loading temperatures above the lithium melting point at 190, 200, 225, 250, and 300. Lithium hydride formation was confirmed with Raman spectroscopy after hydrogen loading. The kinetics of experimental hydride formation was compared to the diffusion-limited Mintz–Bloch model. While the Mintz–Bloch model showed good fit with the experimental loadings, the model overpredicted the loading kinetics starting at 250 °C and at higher temperatures. The overprediction was either caused by lithium hydride outgassing due to some reduction with some residual lithium hydroxide created from brief air exposure when sealing the lithium in the reactor or a transition from diffusion-limited hydride growth to surface or metal–hydride interface-limited hydride growth. [ABSTRACT FROM AUTHOR]

We present results on underwater electrical explosions of thin aluminum and copper foils using a generator delivering ∼200 kA current amplitude, ∼0.9 μs rise time pulses. Time-resolved shadow imaging displays the generation of a strong planar shock wave in water in the vicinity of the exploding foil. Using time-resolved spectroscopy, aluminum oxide (AlO) absorption bands were observed in a Planckian-like spectrum, indicating that aluminum combustion starts when aluminum vaporizes. It is also shown that the strongest shock wave is obtained for the largest linear energy deposition rate to the foil. [ABSTRACT FROM AUTHOR]

Dimensionally stable anodes (DSAs) offer great advantages as insoluble anodes for electrolytic copper foils. Titanium-based iridium dioxide electrode has low oxygen evolution potential, which can reduce energy consumption in industrial production. In view of the excellent oxygen evolution performance of MoS2 in alkaline environment, molybdenum disulfide is considered to be loaded on Ti/IrO2 electrode by electrodeposition to improve the oxygen evolution efficiency of electrolytic copper foil anode in copper sulfate. The structure of the composite anode was characterized using surface analysis techniques such as XRD and SEM. The results manifested that the surface of the anode was shallower and had fewer pits, which effectively improved the microscopic morphology of the Ti/IrO2/MoS2. The oxygen evolution potential of Ti/IrO2/MoS2 composite anode determined by oxygen evolution polarization curve (LSV) was 1.25 V, which was lower than that of commercially available Ti/IrO2-Ta2O5 anodes and had the largest oxygen evolution active surface area. In addition, the experiment with the electrolytic copper foil using the Ti/IrO2/MoS2 anode revealed that the surface flatness of the copper foil was high and the average grain size was 32 nm, which further confirmed that the application of the Ti/IrO2/MoS2 anode in the electrolytic copper foil area can lessen the slot voltage and save cost. [ABSTRACT FROM AUTHOR]

Accurately calculating winding losses has always been a significant challenge in the design of large-capacity medium-frequency transformers. This paper presents an accurate design algorithm for calculating the winding losses of a large-capacity medium-frequency distribution transformer. First, the peculiarities of winding losses in medium-frequency distribution transformers are analyzed. Various commonly used winding conductor types for medium-frequency transformers are introduced. The mechanisms of and differences between AC and DC winding losses in medium-frequency transformers are explained, and an effective analytical method for calculating the AC-to-DC resistance ratio is provided. Finally, the analytical calculation results of different types of winding losses are compared with those obtained through finite element simulations and experimental methods applied to a real transformer prototype. The discrepancies between the analytical results and those obtained using the other two methods were found to be within acceptable error margins, thereby validating the accuracy and effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

[Display omitted] The ever-growing requirement for electrochemical energy storage has exacerbated the production of spent batteries, and the recycling of valuable battery components has recently received a remarkable attention. Among all battery components, copper foil is widely utilized as a current collector for stable zinc platting and stripping in zinc metal batteries (ZMBs) due to the perfect lattice matching of between metal copper and zinc, which is accompanied by the formation of multiple copper-zinc alloy components during the cycling process. Herein, a novel "two birds with one-stone" strategy through a one simple heat treatment step to revive the discarded copper foil in zinc metal battery is reported to further obtain a lithiophilic current collector (Cu x Zn y -Cu) with multiple copper-zinc alloy components on the surface of the discarded copper foil. Such revived Cu x Zn y -Cu current collector greatly reduces the lithium nucleation overpotential and realizes uniform lithium deposition and further inhibits lithium dendrites growth. The formed multiple Cu x Zn y alloy phases on the surface of discarded copper foil exhibit a low Li nucleation overpotential of only 15 mV at 0.5 mA cm−2 for the first cycle. Moreover, such a Cu x Zn y -Cu current collector could achieve stable cycle for 220 cycles at 0.5 mA cm−2 and 110 cycles at 1 mA cm−2 with a Li plating capacity of 1 mAh cm−2. Theoretical calculations indicate that, compared with pure Cu foil, the formed multiple alloy components of CuZn 5 , CuZn 8 , Cu 0.61 Zn 0.39 and CuZn have low adsorption energy of −2.17, −2.55, −2.16 and −2.35 eV with lithium atoms, respectively, which result in reduced lithium nucleation overpotential. The full cell composed of Cu x Zn y alloy current collector with deposition of 5 mAh cm−2 metal Li anode coupled with LiFePO 4 (LFP) cathode exhibits a reversible capacity of 125.6 mAh/g after 110 cycles at a current of 0.5 C with capacity retention of 85.1 %. This work proposed a promising strategy to regenerate the discarded copper foil in rechargeable batteries. [ABSTRACT FROM AUTHOR]

Lithium ion copper foil is prone to oxidation and discoloration on the surface during production, storage-transportation, and use, which directly affects the product yield, reliability, service life and adhesion of lithium batteries. This requires copper foil to have good anti oxidation performance. In this paper, the changes in surface morphology and oxygen content of the copper foil under different soaking and micro electroplating process conditions were studied using characterization methods such as SEM and ED AX. The impact of soaking and micro plating processes on the surface of copper foil surface anti oxidation performance. The results show that when the current density is 5 A/dm², the plating time is 10 s, the chromic anhydride concentration is 0. 5 g/L, and the glucose concentration is 1. 5 g/L. After the copper foil is baked at high temperature, there is no discoloration on the surface, and the anti oxidant performance is better. [ABSTRACT FROM AUTHOR]

Deposition at oblique vapor incidence angles can lead to the growth of thin films with dramatically changed morphological features. Herein, thin-film titanium nanocolumnar arrays were grown on a graphene monolayer/copper foil substrate (TiNCs/Gm-Cufoil) by applying a physical vapor deposition method, through magnetron sputtering at an oblique angle. Ti-nanocolumnar arrays with ca. 200 nm length were developed throughout the substrate with different morphologies depending on the substrate topography. It was found that over the as-fabricated electrocatalyst, the electrooxidation reaction of dopamine is facilitated, allowing quasi-reversible electrooxidation of protonated dopamine to dopamine quinone. Additionally, contrary to works that appeared in the literature, TiNCs/Gm-Cufoil also promotes further quasi-reversible oxidation of leucodopaminechrome to dopaminechrome. The electrode exhibited two linear ranges of dopamine detection (10–90 μM with a sensitivity value of 0.14 μAμM−1cm−2 and 100–400 μM with a sensitivity value of 0.095 μAμM−1cm−2), a good stability over time of about 30 days, and a good selectivity for dopamine detection. [ABSTRACT FROM AUTHOR]

The main methods for suppressing the common mode (CM) noise in flyback converters include adding a shielding layer and adding a balancing winding. To combine the advantages of both methods, a balancing winding with a shielding effect is proposed to suppress CM noise. First, the CM noise transmission path of a flyback converter is analyzed, and an equivalent model of CM noise is established. Then, combined with the CM noise characteristics of the flyback converter, the design criteria for the shielding-balancing winding are given. Finally, experiments are conducted on a flyback converter prototype. The CM noise spectra of four transformer structures (without a shielding layer, with a traditional copper foil shielding layer added, with a balancing winding and with the proposed shielding-balancing winding) are compared. The results show that the CM noise of the flyback converter can be effectively suppressed by adding the shielding-balancing winding proposed in this paper. In addition, the effectiveness of the proposed method is verified. [ABSTRACT FROM AUTHOR]

Liquid crystal polymers (LCPs) should be widely used as substrates in flexible copper clad laminate (FCCL) owing to their unique advantages. However, the poor adhesion of LCPs to copper foils hinders their applications. Considering the good adhesion between polyimides and copper foils, imide groups have previously been introduced into the main chains of LCP molecules. In the present paper, to further enhance the adhesion of the LCPEIs, the 1‐hydroxy‐7‐azabenzotriazole (HOAt) is used to terminate the main chains of LCPEI molecules, which arises from the excellent coordination interaction between the azabenzotriazole groups and copper ions. Thus, the liquid crystal poly(ester imide) (t‐LCPEI), carboxyl‐terminated liquid crystal poly(ester imide) (c‐LCPEI), and azabenzotriazole‐terminated liquid crystal poly(ester imide) (a‐LCPEI) were synthesized. The results showed that LCPEIs possessed liquid crystallinity, and the peel strength of a‐LCPEI film to copper foils was increased by about 140% and nearly 43%, respectively, compared to that of LCP and t‐LCPEI. Moreover, a‐LCPEI showed higher glass transition temperature (Tg = 211°C) than conventional LCP resins (Tg = 155°C, Vectra A), and excellent thermal properties. Meanwhile, the dielectric constant and loss of a‐LCPEI were as low as 3.04 and 9.7 × 10−3 at 10 GHz, respectively. These findings indicate that the azabenzotriazole‐terminated LCPEI is suitable to be used as the substrate material for high‐performance FCCL, and the work provides a feasible approach to enhance the adhesion and maintain the other outstanding properties of LCP. [ABSTRACT FROM AUTHOR]

2D hexagonal boron nitride (h‐BN), which has a similar honeycomb lattice structure to graphene, is a promising dielectric material for a wide variety of applications. Herein, the growth of high‐quality and large‐size multilayer h‐BN crystals on Cu foils is reported by chemical vapor deposition (CVD) at atmospheric pressure. The size of an individual isolated hexagonal crystal of h‐BN is about 20 µm, and the thickness is 3 nm. This paper studies the variables that affect h‐BN growth during the process and the microstructure changes during the growth. Through analysis of the thermal and dynamic processes of chemical vapor deposition, relationships are derived between the mass of h‐BN grown in the gas phase and various temperature and pressure factors. This information is used to develop appropriate parameters for commercial copper foil growth. Finally, using optimized conditions, high‐quality h‐BN at high pressure and low gas flow conditions are grown. [ABSTRACT FROM AUTHOR]

Purpose: A daily quality assurance (QA) check in proton therapy is ensuring that the range of each proton beam energy in water is accurate to 1 mm. This is important for ensuring that the tumor is adequately irradiated while minimizing damage to surrounding healthy tissue. It is also important to verify the total charge collected against the beam model. This work proposes a time-efficient method for verifying the range and total charge of proton beams at different energies using a multilayer Faraday collector (MLFC). Methods: We used an MLFC-128-250 MeV comprising 128 layers of thin copper foils separated by thin insulating KaptonTM layers. Protons passing through the collector induce a charge on the metallic foils, which is integrated and measured by a multichannel electrometer. The charge deposition on the foils provides information about the beam range. Results: Our results show that the proton beam range obtained using MLFC correlates closely with the range obtained from commissioning water tank measurements for all proton energies. Upon applying a range calibration factor, the maximum deviation is 0.4 g/cm2. The MLFC range showed no dependence on the number of monitor units and the source-to-surface distance. Range measurements collected over multiple weeks exhibited stability. The total charge collected agrees closely with the theoretical charge from the treatment planning system beam model for low- and mid-range energies. Conclusions: We have calibrated and commissioned the use of the MLFC to easily verify range and total charge of proton beams. This tool will improve the workflow efficiency of the proton QA. [ABSTRACT FROM AUTHOR]

Practical aqueous zinc‐ion batteries require low‐cost thin zinc anodes with long‐term reversible stripping/depositing. However, thin zinc anodes encounter more severe issues than thick zinc, such as dendrites and uneven stripping, resulting in subpar performance and limited lifetimes. Here, this work proposes a three‐in‐one zinc anode obtained by a large‐scale two‐step method to address the above issues. In a three‐in‐one zinc anode, the copper foil as an inactive current collector solves the gradual reduction of the active area when only the pure zinc as an active current collector. This work develops an automatic electroplating device that can continuously deposit a zinc layer on a conducting foil to meet the demand for zinc‐coated copper foils. The sodium carboxymethylcellulose (CMC)‐zinc fluoride (ZnF2) protective layer prevents direct contact between zinc and separator, and provides a uniform and sufficient supply of zinc ions. The CMC‐ZnF2‐coated copper foil performs up to 3000 reversible zinc deposition/stripping cycles with a cumulative capacity of 6 Ah cm−2 and an average Coulombic efficiency of 99.94%. The Zn||ZnVO cell using the three‐in‐one anode achieved a high capacity retention of over 70% after 15 000 cycles. The proposed three‐in‐one anode and the automatic electroplating device will facilitate industrialization of practical thin zinc anodes. [ABSTRACT FROM AUTHOR]

Ti/IrO2-Ta2O5 electrodes are extensively utilized in the electrochemical industries such as copper foil production, cathodic protection, and wastewater treatment. However, their performance degrades rapidly under high current densities and severe oxygen evolution conditions. To address this issue, we have developed a composite anode of Ti/Ta-Ti/IrO2-Ta2O5 with a Ta-Ti alloy interlayer deposited on a Ti substrate by double-glow plasma surface alloying, and the IrO2-Ta2O5 surface coating prepared by the traditional thermal decomposition method. This investigation indicates that the electrode with Ta-Ti alloy interlayer reduces the agglomerates of precipitated IrO2 nanoparticles and refines the grain size of IrO2, thereby increasing the number of active sites and enhancing the electrocatalytic activity. Accelerated lifetime tests demonstrate that the Ti/Ta-Ti/IrO2-Ta2O5 electrode exhibits a much higher stability than the Ti/IrO2-Ta2O5 electrode. The significant improvement in electrochemical stability is attributed to the Ta-Ti interlayer, which offers high corrosion resistance and effective protection for the titanium substrate. [ABSTRACT FROM AUTHOR]

A copper/polydimethylsiloxane (Cu/PDMS) microfluidic chip was designed to synthesize SERS substrates through a displacement reaction between silver and copper in microfluidic channels to form a microfluidic SERS nanoparticles (AgNPs)/Cu chip. This SERS substrate fabrication method doesn't require complex manufacturing processes or expensive equipment, and it can be achieved at room temperature in just 4 min. Meanwhile, the AgNPs grown on copper foil could offer ample hot spots, effectively boosting Raman signals of target molecules, and the enhancement factor (EF) was 5.12 × 107 for methylene blue, 4.08 × 107 for crystal violet, and 4.81 × 105 for sulfadiazine. The chip could be reused at least 9 times with consistent signal performance. Combined with the concentration gradient microchannel network design, we could establish the standard curve for samples through one injection on a single chip. A rapid SERS method for detecting sulfadiazine in aquatic products was developed. The linear range for sulfadiazine analysis was 75.0–1000 μg L−1 with a limit of detection of 28.4 μg L−1. Sulfadiazine was found in aquatic products (43.8 μg kg−1), with recovery rates ranging from 82.7% to 110%. The result was validated using high-performance liquid chromatography, showing a relative error of 9.3%. The entire detection procedure could be completed in just 20 min to detect sulfadiazine. These results demonstrate that the developed SERS method is fast, accurate, and reliable for analysis of sulfadiazine in aquatic products. [ABSTRACT FROM AUTHOR]

In this research, CZTS thin films were grown on flexible Cu-foil substrates with varying sulfurization times. Distinct characterization methods were employed, including X-ray diffraction (XRD), Raman spectroscopy, EnergyDispersive X-ray Spectroscopy (EDX), Scanning Electron Microscopy (SEM), optical transmission, and Photoluminescence (PL) measurements. Distinctive diffraction peaks characteristic of the kesterite CZTS phase were observed in the XRD analysis, occurring around at 2θ= 28.45° (112), 47° (220/204), and 56° (312/116). Additionally, some secondary phases such as Cu2S and SnS were identified. Raman spectroscopy confirmed the presence of the kesterite CZTS phase, with a prominent peak detected at approximately ~336 cm-1, attributed to sulfur atom vibrations within the kesterite structure. Apart from CZTS structure, minor peaks suggesting the presence of the Cu2SnS3 (CTS) phase was detected. EDX analysis revealed compositions with Cu-poor content and Zn-rich content across all samples, with slight variations in sulfurization dwell times affecting the chemical composition. SEM imaging at different magnifications showed alterations in surface morphology and grain structures. Films sulfurized for 30 s and 60 s displayed a granular structure morphology, while extending the dwell time to 120 s resulted in a more compact surface morphology. Optical band gap values ranged between 1.57 and 1.60 eV. PL measurements consistently exhibited strong PL emission around 1.25 eV for all samples, attributed to various transitions within the band structure of CZTS film. The absence of observable band-to-band transitions in the PL measurements indicated the presence of intrinsic defect levels and recombination centers within CZTS. Overall, it was demonstrated in this study that CZTS thin films can be produced on flexible Cu-foils with short sulfurization times, thereby expanding the application areas of CZTS thin-film solar cells. [ABSTRACT FROM AUTHOR]

Aqueous trivalent metal batteries represent a compelling candidate for energy storage due to the intriguing three‐electron transfer reaction and the distinct properties of trivalent cations. However, little research progress has been achieved with trivalent batteries due to the inappropriate redox potentials and drastic ion hydrolysis side reactions. Herein, the appealing yet underrepresented trivalent indium is selected as an advanced metal choice and the crucial effect of substrate on its plating mechanism is revealed. When copper foil is used, an indiophilic indium‐copper alloy interface can be formed in situ upon plating, exhibiting favorable binding energies and low diffusion energy barriers for indium atoms. Consequently, a planar, smooth, and dense indium metal layer is uniformly deposited on the copper substrate, leading to outstanding plating efficiency (99.8–99.9%) and an exceedingly long lifespan (6.4–7.4 months). The plated indium anode is further paired with a high‐mass‐loading Prussian blue cathode (2 mAh cm−2), and the full cell (negative/positive electrode capacity, N/P = 2.5) delivers an excellent cycling life of 1000 cycles with 72% retention. This work represents a significant advancement in the development of high‐performance trivalent metal batteries. [ABSTRACT FROM AUTHOR]

Electrolytic copper foils are functional basic raw material in the electronics manufacturing industry. Due to different electrolytic process conditions (such as types of additives, current density, electrodeposition time, etc.), different microstructures will be formed during the raw foil manufacturing process, such as grain size, morphology, twinning, and texture. These microstructures are closely related to the performance of the electrolytic copper foil (ECF). Texture is one key aspect among them, as it affects various properties of ECF to a certain extent, including tensile strength, elongation, and hardness. Therefore, texture is receiving increasing research attention. This article reviews recent studies on the texture of ECF, analyzes the influence of electrolytic process conditions on the formation of texture, and explores the intrinsic relationship between texture and the mechanical properties of ECF. It also provides an outlook on the mechanisms for the study of ECF texture and its future development. [ABSTRACT FROM AUTHOR]

The comparative analysis of the structural, morphological, and local electrical properties of CVD graphene films synthesized at atmospheric and low pressure CVD growth conditions was carried out. The use of electrical techniques of scanning probe microscopy, such as Kelvin probe force microscopy, scanning capacitance microscopy, electrostatic force microscopy, and conductive atomic-force microscopy for investigation of heterogeneous graphene coverage was discussed. A significant change in the surface potential values was observed indicating the formation of p-type multilayered graphene domains on single layer graphene at low pressure and n-type multilayered graphene films at atmospheric pressure CVD. The effect of Ar flow rate increasing during cooling stage in the temperature range of 700–200 °C causing graphite formation was described. The employment of surface potential spectroscopy allows to indicate the presence of nonlinear phenomena in heterogeneous graphene. [ABSTRACT FROM AUTHOR]

Sodium metal anode is considered the most promising alternative to lithium due to its cost‐effectiveness and widespread availability. To realize its practical applications, numerous strategies have been devised in metallic Na and electrolyte to enhance the cycle life. However, the improvements in 2D current collector in ester‐based electrolyte remain limited. Herein, a two‐alloys‐layer modified current collector (Na15Sn4/Cu6Sn5/Cu) has been constructed through electrodeposition and sodiation processes. The Na15Sn4/Cu6Sn5 alloys‐layer guarantees the dense plating of Na and establishes a credible connection between Na and substrate. The failure of sodium anode is attributed to the depletion of ester‐based electrolyte resulting from their side reactions, which could be mitigated on Na15Sn4 surface. Thus, the asymmetric cell, containing merely 100 µL electrolyte, achieves efficient Na plating/stripping for 110 times with an average Coulombic efficiency of 94.9%, which is superior than those reported using excessive fluorine‐rich electrolytes. The full cell consisting of an anode with 3 mAh cm−2 of Na on Na15Sn4/Cu6Sn5/Cu and a Na3V2(PO4)3 cathode demonstrates a capacity retention rate of 96% after 200 cycles at 1.0 C. By improving the Coulombic efficiency solely through the modified copper foil, this work provides a new route for the practical application of Na anode in ester‐based electrolytes. [ABSTRACT FROM AUTHOR]

Aqueous Zn metal batteries are emerging as a promising candidate for the next‐generation largescale energy storage system due to their high safety, low lost, and eco‐friendliness. Nevertheless, their practical application is restricted by the uncontrollable Zn dendrite growth and the limited utilization of the Zn metal anode. Herein, a room temperature electrodeposition strategy based on an optimized rate relationship between the diffusion and consumption of Cu2+ to prepare a (111)‐textured Cu current collector for the construction of the dendrite‐free Zn metal anode with high reversibility is developed. Attributed to the high lattice match between the (002) facet of Zn with the (111) facet of Cu, the deposition of Zn along its [001] orientation is achieved on the (111)‐textured Cu. The (002) facets horizontally aligned with the current collector endow Zn with the dendrite‐free planar construction and superior corrosion resistance, resulting in a high reversibility with a long life‐span over 2186 cycles. Impressively, the resultant Zn anodes can stabilize the operation of pouch cells with an extremely demanding negative‐to‐positive capacity ratio of 2. This work provides a new avenue for the development of the current collectors for the low‐cost sustainable energy storage. [ABSTRACT FROM AUTHOR]

Anode‐free sodium batteries (AFSBs) are a desirable choice for high‐energy‐density and low‐cost battery systems. However, the rapid capacity decline resulting from irreversible sodium plating and stripping remains a big challenge for AFSBs. Herein, a copper‐dominated Cu2Sb composite coating employing a co‐sputtering strategy is designed to improve the sodophilicity of copper foils. The Cu2Sb coating can construct a durably sodophilic and stable interface by suppressing the alloying transition of the sodophilic phase and alleviating the volumetric deformation of the coating. This stable alloy interface can greatly enhance sodium nucleation and improve ion transport at the interface by forming homogeneous NaF‐rich solid electrolyte interphase (SEI) film. Ultimately, the AFSB assembled using this unique substrate with a highly loaded Na3V2(PO4)3 (NVP) cathode (≈10 mg cm−2) can cycle 600 cycles deliver a discharge capacity of 75.4 mAh g−1 with a capacity retention of 74.2%, which is much higher than those of the untreated one or antimony coating one (<30% after 200 cycles). This co‐sputtering strategy provides new insights into the design of sodophilic coatings with sodium‐alloying ability and can be extended to the optimization of zinc‐metal batteries. [ABSTRACT FROM AUTHOR]

Due to the direct contact between the probe and sample, the contact of the four-probe method is important for the structural integrity of the sample and the accuracy of electrical resistivity measurements, especially for surface-coated metal foils with multilayered structures. Here, we analyzed the accuracy and stability of four-probe method probing on different sides of copper (Cu) foils covered with graphene (Gr). Theoretical simulations showed similar potential distributions on the probe tip when probing on the Cu and Gr sides. The resistivity of the Gr/Cu foil was 2.31 ± 0.02 μΩ·cm when measured by probing on the Cu side, and 2.30 ± 0.10 μΩ·cm when measured by probing on the Gr side. The major difference in the mean deviation is attributed to surface damage. In addition, the method of probing on the Cu side was sensitive to the resistivity changes of Gr induced by polymers with a dielectric constant range of 2~12, which is consistent with the calculations based on the random phase approximation theory. Our results demonstrated that the probing position on the metal side in the four-probe method can effectively protect the structural integrity of the functional surface-coated layer and maintain the high sensitivity of the measurement, providing guidance for the resistivity measurements of other similarly heterogeneous materials. [ABSTRACT FROM AUTHOR]

In this study, an electrode slurry composed of molybdenum disulfide (MoS2) and vapor-grown carbon fiber (VGCF) prepared through a solid-phase synthesis method was blade-coated onto copper foil to form a thick film as the anode for lithium-ion batteries. In previously reported work, MoS2-based lithium-ion batteries have experienced gradual deformation, fracture, and pulverization of electrode materials during the charge and discharge cycling process. This leads to an unstable electrode structure and rapid decline in battery capacity. Furthermore, MoS2 nanosheets tend to aggregate over charge and discharge cycles, which diminishes the surface activity of the material and results in poor electrochemical performance. In this study, we altered the density of the MoS2–carbon fiber/Cu foil anode electrode by rolling. Three different densities of electrode sheets were obtained through varying rolling repetitions. Our study shows the best electrochemical performance was achieved at a material density of 2.2 g/cm3, maintaining a capacity of 427 mAh/g even after 80 cycles. [ABSTRACT FROM AUTHOR]

Despite rechargeable aqueous Zn‐ion batteries (AZIBs) exhibit advantages such as high safety, high specific energy, and low cost, etc, the implementation of Zn anodes is still hampered by insufficient cyclability and grievous side reactions. To improve the cycling stability of the zinc anode, a stable zinc anode/electrolyte interface is needed to suppress dendrite formation and side reactions. Herein, a self‐regulating endogenous organic–inorganic hybrid interface layer (EHI) in situ on the surface of the Zn anode by regulating solvent molecules is constructed. The EHI consists of an organic outer layer containing N─H and ─CH3 and an inorganic inner layer containing ZnO and ZnCO3, which effectively inhibits hydrogen evolution and dendrite growth. Consequently, AZIBs with the EHI achieve a lifespan exceeding 5500 h in 3 mA cm−2, and stripping/plating on copper foils for 600 cycles with an average coulomb efficiency (CE) of 99.47%. This study provides a feasible idea for realizing stable and reversible zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal, with its unparalleled theoretical capacity and lowest electrochemical potential, is a promising anode material for rechargeable batteries. Yet, challenges such as dendrite formation, severe electrode volume change, and ongoing Li consumption impede its practical adoption. To address these challenges, a novel approach is introduced, harnessing the switchable electrical conductivity of a nanoporous current collector for Li metal anode. A vertically aligned Nickel‐catecholate (VANC) is directly grown on the copper foil as the nanoporous current collector, and the Li intercalation and de‐intercalation of VANC reversibly decrease and increase the electrical conductivity in the direction perpendicular to the electrode, respectively. The switchable conductivity induces uniform deposition and stripping of Li metal without forming dendrite and dead Li during the Li plating/stripping process and thus enables high coulombic efficiency of over 98% even after 200 cycles. This nanoporous structure with switchable conductivity will open up a new path for reliable lithium metal anode for rechargeable battery applications. [ABSTRACT FROM AUTHOR]

With the increasing demand for innovative electronic products, LED transparent screens are gradually entering the public eye. Polyimide (PI) materials combine high temperature resistance and high transparency, which can be used to prepare flexible copper-clad laminate substrates. The physical and chemical properties of PI materials differ from copper, such as their thermal expansion coefficients (CTEs), surface energy, etc. These differences affect the formation and stability of the interface between copper and PI films, resulting in a short life for LED transparent screens. To enhance PI-copper interfacial adhesion, aminopropyl-terminated polydimethylsiloxane (PDMS) can be used to increase the adhesive ability. Two diamine monomers with a trifluoromethyl structure and a sulfone group structure were selected in this research. Bisphenol type A diether dianhydride is a dianhydride monomer. All three of the above monomers have non−coplanar structures and flexible structural units. The adhesion and optical properties can be improved between the interface of the synthesized PI films and copper foil. PI films containing PDMS 0, 1, 3, and 5 wt% were analyzed using UV spectroscopy. The transmittance of the PI-1/3%, PI-1/5%, PI-2/3%, and PI-2/5% films were all more than 80% at 450 nm. Meanwhile, the Td 5% and Td 10% heat loss and Tg temperatures decreased gradually with the increase in PDMS. The peel adhesion of PI-copper foil was measured using a 180° peel assay. The effect of PDMS addition on peel adhesion was analyzed. PIs-3% films had the greatest peeling intensities of 0.98 N/mm and 0.85 N/mm. [ABSTRACT FROM AUTHOR]

This article discusses an interesting method to synthesize copper oxide films on a copper foil for photoelectrochemical (PEC) water-splitting applications. A simple, and low-cost, non-thermal plasma (NTP) jet on a copper foil with an Ar/O2 gas mixture in ambient air are used. The NTP exposure times used to synthesize the CuO films on Cu foil were 10 s, 20 s, and 30 s. The prepared films were subjected to different apparatus and techniques. X-ray diffraction tests showed that the prepared films were polycrystalline with sharp peaks. Field-emission scanning electron microscopy (FE-SEM) revealed the morphology of the modified surface of the CuO films, the images showing that the films consist of homogeneous and well-distributed nanoparticles. These films were a photocathode using a three-electrode homemade Teflon PEC with a quartz window and a Keithley-2430 source meter. An increased photocurrent was obtained via water-splitting under full-spectrum xenon light with a photoconversion efficiency of up to 6.45%. The increased PEC water splitting was mostly due to the creation of many electron–hole pairs. This research could pave the way for a more efficient CuO-based photocathode for PEC. [ABSTRACT FROM AUTHOR]

To investigate the feasibility and formation laws of fabricating micro-dimples induced by near-wall laser-induced cavitation bubble (LICB) on 7050 aluminum alloy. A high-speed camera and a fiber-optic hydrophone system were used to capture pulsation evolution images and acoustic signals of LICB. Meanwhile, a three-dimensional profilometer was employed to examine the contour morphology of the surface micro-dimple on the specimen. The results show that at an energy level of 500 mJ, the total pulsation period for the empty bubble is 795 μs, with individual pulsation periods of 412.5 μs, 217 μs, and 165 μs for the first, second, and third cycles, respectively, with most energy of the laser and bubble being consumed during the first evolution period. Under the synergy of the plasma shock wave and collapse shock wave, a spherical dimple with a diameter of 450 μm is formed on the sample surface with copper foil as the absorption layer. A model of micro-dimple formed by LICB impact is established. As the energy increases, the depth of the surface micro-dimple peaks at an energy of 400 mJ and then decreases. The depth of the surface micro-dimple increases with the increase in the number of impacts; the optimal technology parameters for the micro-dimple formation by LICB impact are as follows: the absorption layer is copper foil, the energy is 400 mJ, and the number of impacts is three. [ABSTRACT FROM AUTHOR]

The need to manufacture components out of copper is significantly increasing, particularly in the solar technology, semiconductor, and electric vehicle sectors. In the past few decades, infrared laser (IR) and green laser (GL) have been the primary technologies used to address this demand, especially for small or thin components. However, with the increased demand for energy saving, alternative joint techniques such as blue diode laser (BDL) are being actively explored. In this paper, bead-on-plate welding experiments on 0.2 mm thick pure copper samples employing a BDL are presented. Two sets of parameters were carefully selected in this investigation, namely Cu-1: Power (P) = 200 W; Speed (s) = 1 mm/s; and angle = 0°, and Cu-2: P = 200 W; s = 5 mm/s; and angle = 10°. The results from both sets of parameters produced defect-free full penetration welds. Hardness test results indicated relatively softer weld zones compared with the base metal. Tensile test samples fractured in the weld zones. Overall, the samples welded with Cu-1 parameters showed better mechanical properties, such as strength and elongation, than those welded with the Cu-2 parameters. The tensile strength and elongation obtained from Cu-1 were marginally lower than those of the unwelded pure copper. The outcomes from this research provide an alternative welding technique that is able to produce reliable, strong, and precise joints, particularly for small and thin components, which can be very challenging to produce. [ABSTRACT FROM AUTHOR]

As microelectronic technology advances, electronic devices have become faster and smaller. The electromagnetic radiation has negative effects on electronic device operation, how to eliminate the electromagnetic radiation has attracted much attention. Copper foil is the most commonly used and effective material for reducing electromagnetic radiation. In practical applications, it is necessary to use adhesive to fix it onto the surface of electronic devices. In this work, an integrated electromagnetic shielding material (AgPs/TPU@Cu hybrid film) was designed and prepared by a facile way, in which the mixture of silver particles (AgPs) and thermoplastic polyurethane (TPU) was cured to form a AgPs/TPU composite film on the surface of copper foil (Cu) by a one-pot heating press processing. The horizontal and vertical electrical resistances of AgPs/TPU composite film decreased to 0.2 Ω and 0.47 Ω at the AgPs loading of 38 wt%, respectively, and the corresponding thermal conductivity reached 0.81 W m−1 K−1. Moreover, the AgPs/TPU@Cu hybrid film at the AgPs loading of 38 wt% exhibited the maximum electromagnetic interference shielding effectiveness (EMI SE) value of 105 dB. This work provides valuable information about EMI shielding technologies for practical electronic applications. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a miniature quadrupedal piezoelectric robot with a mass of 1.8 g and a body length of 4.6 cm. The robot adopts a novel spatial parallel mechanism as its transmission. Each leg of the robot has two degrees of freedom (DOFs): swing and lift. The trajectory necessary for walking is achieved by the appropriate phasing of these two DOFs. A new manufacturing method for piezoelectric actuators was developed. During the stacking process, discrete patterned PZT pieces are used to avoid dielectric failure caused by laser cutting. Copper-clad FR-4 is used as the solder pad instead of copper foil, making the connection between the pad and the actuator more reliable. The lift powertrain of the robot was modeled and the link length of the powertrain was optimized based on the model. The maximum output force of each leg can reach 26 mN under optimized design parameters, which is 1.38 times the required force for successful walking. The frequency response of the powertrain was measured and fitted to the second-order system, which enabled increased leg amplitudes near the powertrain resonance of approximately 70 Hz with adjusted drive signals. The maximum speed of the robot without load reached 48.66 cm/s (10.58 body lengths per second) and the payload capacity can reach 5.5 g (3.05 times its mass) near the powertrain resonance. [ABSTRACT FROM AUTHOR]

Synthesis of high quality and quantity of graphene by cost-effective methods are highly desirable for various application. In electrochemical exfoliation, graphite foil has been used as carbon source for the synthesis of high yield of graphene flakes. Electrochemical exfoliation is one of the faster and cheaper method to synthesize graphene sheets. In this work, five different types of concentration of sulphuric acid were used for electrochemical exfoliation. The electrochemical cell design where graphite foil as anode and copper foil as cathode which were connected to DC power supply of 5V. To examine the morphology scanning electron microscope (SEM) was employed in which the sheet structures with large lateral dimension and thin graphene flakes. Furthermore, X-ray diffraction (XRD) revealed that exfoliated graphene samples showed a significant peak at about 2θ = 26º corresponded to graphite. [ABSTRACT FROM AUTHOR]

Metallic copper is widely used as current collector (CC) for graphite anode of lithium-ion batteries (LIBs) due to its high electrical conductivity and electrochemical stability. However, the large volume density of commercial copper foil (∼8.9 g·cm−3) limits the increase of energy density of battery. Here, copper-coated porous polyimide (Cu@PPI) was prepared by vacuum evaporation as collector for the graphite anode. The sandwich structure connects the copper metal on both sides of the collector with excellent electrical conductivity. Compared to commercial Cu foil, Cu@PPI has lighter mass (≤3.9 mg for disc of 12 mm diameter versus 9.9 mg of ∼10 µm Cu foil) and lower volume density (≤3.3 g·cm−3). In addition, the porous structure allows of better adhesion of reactive substances and electrochemical properties than pure Cu foils. It is estimated that the energy density of Cu@PPI should be much higher than that of Cu foil. This strategy should be applicable for other current collectors. [ABSTRACT FROM AUTHOR]

This paper proposes a novel inductive and capacitive combined wireless power transfer (IC-WPT) system for unmanned aerial vehicle (UAV) applications. First, a new compact inductive and capacitive combined coupler is presented. The magnetic field coupled power transmission of the compact coupler contains one magnetic transmitting unit, which is composed of two biorthogonal L-type cores and two rectangular coils wound on each of the short edges of the L-type ferrite core in the vertical position, and two air-cored receiving coils embedded in the legs. Meanwhile, the electric field coupled power transmission of the compact coupler consists of four pieces of copper foil, where two are attached on the primary side and two are attached on the secondary sides for wireless energy transmission through capacitive coupling. Second, a simple resonant compensation network is developed for the IC-WPT system. To make the secondary side lightweight, the receiver self-inductance of the inductive power transfer (IPT) coupler and compensating capacitance of the capacitive power transfer (CPT) receiver can be used to compensate each other. A prototype of the proposed UAV IC-WPT system is built and tested. Experimental results show that the wireless power transfer system can deliver 130 W at an efficiency of 81.2%, which means it can be adopted to the autonomous charging of UAVs. [ABSTRACT FROM AUTHOR]

A 500 MHz high temperature superconducting (HTS) and low temperature superconducting (LTS) hybrid NMR magnets with conduction cooling has been designed in the paper, in which the HTS insert magnet is designed and fabricated with an intra-layer no-insulation (LNI) layer-wound coil structure. An equivalent circuit model considering layer-wound coil helical structure coupled with a stacked homogenization T-A model is used to study the screening current behaviors and magnetic field homogeneity of the HTS-LTS hybrid NMR magnet. It can be found that the maximum value of the time constant of the LNI layer-wound coil is only determined by the copper foil resistance, which ensures a smaller charging delay. The screening current induced by self field and some special background field, which does not change the original radial magnetic flux direction of the LNI HTS magnet, optimizes the magnetic field homogeneity. The screening current induced by the LTS compensation coils is the reason for the deterioration of magnetic field homogeneity. Then, we use the screening current property to readjust the parameters of the background magnets, which make the homogeneity of the NMR magnet optimized. [ABSTRACT FROM AUTHOR]

Copper foils demonstrate a tendency for self-annealing, which adversely impacts the stability of the products. The self-annealing induced recrystallization of copper foil is closely related to the grain growth mode. When copper foil grows in equiaxed grain mode, resulting in a decrease in tensile strength from 780 MPa to 330 MPa. Conversely, the columnar grain copper foil exhibits excellent room-temperature stability in mechanical properties. The mechanism of copper foil room temperature self-annealing behavior was put forward. It was found that the internal stress generated in the process of preparing copper foils is the key factor driving the recrystallization of equiaxed grains. This internal stress originates from nanocrystals and high-density dislocations, with the latter arising from the doping of organic elements. The initial high stress values and the plasticity of dislocations contributed to a noteworthy decrease in residual stress. As dislocation plasticity ensues, the anchoring of interstitial atoms gives rise to dislocation loops. The interaction between dislocation loops and coincident twin boundaries induces the formation of twin steps. The quantity of twins of equiaxed copper foil increases greatly after self-annealing. Conversely, the initial dislocation density of columnar grain copper foil is an order of magnitude lower than that of equiaxed grains.

In this work, the formability of copper foils was analyzed based on a series of multi-step micro deep drawing (MMDD) tests. The copper foils were annealed at temperatures ranging from 300 to 700 °C for 5 min, followed by tensile tests and electron backscatter diffraction (EBSD) tests for the exploration of mechanical behavior and microstructural characterization of annealed specimens. The results show that the as-received copper foils exhibit poor formability and cannot form micro cups during MMDD. When the annealing temperature attains 500 °C, a homogeneous microstructure was formed inside copper foils, enhancing the formability of materials and improving the surface quality of formed products. Nevertheless, both the elongation and tensile strength decrease dramatically due to the easy occurrence of incoordination deformation in coarse grain bands with further increase in annealing temperature to 700 °C. Consequently, marked wrinkling is generated on the surface of drawn cups and obvious thinning occurs at the nose radius region due to metal flow. In addition, the results show that the E texture component within the copper foils is favorable for MMDD. Overall, an optimal annealing temperature of 500 °C is obtained with improved formability of copper foils and forming quality of drawn cups.

Plasma treatment was used to improve the surface roughness of copper foil. The copper‐clad laminates reinforced with carbon fiber, boron nitride (BN), or boron carbide (B4C), and epoxy resin were prepared by hot pressing. The effect of BN or B4C content on the physical properties and tribological properties of copper‐clad laminates reinforced with carbon fiber and epoxy resin were studied. The resulting copper‐clad laminate exhibited desirable properties, such as dielectric constant, peel strength, oxygen index, and arc resistance, which were influenced by the concentration of BN or B4C particles. Additionally, the wear and friction properties of the laminate were evaluated, revealing the effects of load, sliding speed, and particle content on weight loss, specific wear rate, and coefficient of friction. SEM analysis of worn surfaces provided insight into the stages of wear, highlighting the importance of an oxide layer in reducing wear and protecting the copper surface. [ABSTRACT FROM AUTHOR]

A novel finding that the electrochemical performance of the commercial lithium titanate (Li4Ti5O12, LTO) can be significantly improved by using a novel current collector of CuI particles modified copper foil is reported for the first time in this work. Firstly, a large number of particles with well-defined shapes were prepared on the commercial copper foil surface via a very simple soaking process, in which the soaking solution contained only CuSO4, H2SO4 and [Bmim]I. As indicated by the XRD and XPS measurements, the particles observed on the surface of the copper foil were identified as CuI particles. That is, CuI particles modified copper foils (denoted as CuI/Cu) were successfully prepared at room temperature. CuI/Cu prepared in the presence of 0.4, 0.6 and 0.8 g of [Bmim]I were nominated as CF (copper foil) a, b and c, respectively. Inconceivably, as compared to the conventional LTO electrode, the LTO electrodes assembled using the newly prepared CFs exhibited a significantly improved electrochemical performance, i.e., all as-prepared CFs showed an evident promoting effect on the electrochemical performance of the traditional LTO electrodes. For instance, the initial discharge capacity (DC) of the LTO electrode assembled using CF b (called electrode b) at 0.2 C was 307 mAh g−1, which was about 1.86 times higher than that of the LTO electrode prepared using the conventional copper foil current collector (165 mAh g−1). Particularly, as the applied current rate was as high as 10 C, the DC value of electrode b (117 mAh g−1), even after 100 cycles, was still about 2.54 times that of the traditional LTO electrode (46 mAh g−1). In this preliminary work, a new method for preparing CuI particles was developed, along with a novel approach to significantly improve the electrochemical properties of the commercial LTO electrode. The method did not require any strong oxidants or reducing agents, nor did it demand any additional energy expenditure during the preparation of CuI particles. Moreover, the approach did not require any changes in the assembly procedure for the LTO electrodes being studied. This work was very meaningful for the development of the CuI-related research field as well as for the electrochemical performance improvement of LTO-based lithium-ion batteries (LIBs). [ABSTRACT FROM AUTHOR]

This paper presents the implementation of high-energy-resolution off-resonant spectroscopy (HEROS) measurements using self-seeded x-ray free-electron laser (XFEL) pulses. This study systematically investigated XFEL conditions, including photon energy and accumulated shot numbers, to optimize the measurement efficiency for copper foil samples near the K-edge. The x-ray absorption spectra reconstructed using HEROS were compared with those derived from fluorescence-yield measurements. The HEROS-based spectra exhibited consistent line shapes independent of the sample thickness. The potential application of HEROS to high-temperature copper was also explored. HEROS offers distinct advantages including scan-free measurement of x-ray absorption spectra with reduced core-hole lifetime broadening and self-absorption effects. Using self-seeded XFEL pulses, HEROS facilitates single-shot-based pump–probe measurements to investigate the ultrafast dynamics in various materials and diverse conditions. [ABSTRACT FROM AUTHOR]

In this work, we use electrolytic copper foils as substrates for the deposition of graphene by chemical vapor deposition. We investigate the effects of preannealing conditions, methane injection time, and temperature to synthesize graphene with a similar quality as when grown on cold-rolled copper. We find that the electrolytic copper foil's annealing conditions and CH4 injection temperature determine the quality of graphene. [ABSTRACT FROM AUTHOR]

A novel finding that rock-shaped CuBr particles can be prepared onto the commercial copper foil surface (denoted as CuBr/Cu) through using a room temperature soaking approach is presented for the first time in this preliminary work. The soaking solution only contained 0.7 M CuSO4 and a very small amount of benzyltrimethylammonium bromide (C10H16NBr, denoted as BTABr). The commercial bare copper foil was called as foil o, and the samples of CuBr/Cu fabricated in the presence of 5 mM, 10 mM, and 15 mM BTABr were respectively nominated as foil a, b, and c. Correspondingly, the tin dioxide (SnO2) electrodes prepared using foil o, a, b, and c were noted as electrode o, a, b, and c, respectively. To one's surprise, in comparison with electrode o, electrode a, b, and c delivered a significantly promoted electrochemical performance. For instance, the initial discharge capacity (DC) of electrode b measured at 0.2 A g−1 was about 1249 mAh g−1, being about 1.78 times that of electrode o (699 mAh g−1). More than that, even at 1.0 A g−1 after 50 cycles, the DC value of electrode b (194 mAh g−1) was still measured to be about 1.88 times that of electrode o (103 mAh g−1). A soaking method to prepare rock-shaped CuBr particles and a groundbreaking approach to dramatically promote the electrochemical performance of the routine SnO2 electrode are presented in this work, which is very beneficial to both the progress of CuBr-based material research field and the further development of SnO2 related lithium ion batteries (LIBs). [ABSTRACT FROM AUTHOR]

Large area single and bilayer graphene are grown on Pt/Ti/SiO2 substrates by hot filament chemical vapor deposition (HFCVD) with and without the assistance of Cu foil. The quality and number of graphene layers deposited on the substrate are assessed by Raman Spectroscopy. Atomic Force Microscopy (AFM) is used for assessing the surface topography of the graphene films grown on the Pt/Ti/SiO2 substrates. The microstructure and elemental analyses are performed by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The results show that bilayer graphene growth is facilitated by a copper foil placed nearby Pt/Ti/SiO2 substrate and by a high filament temperature in the HFCVD reactor. Monolayer graphene grows only when no copper foil is placed near the Pt/Ti/SiO2 substrate at a low filament temperature. The approach paves a novel pathway towards the layer‐controlled growth of graphene on Pt/Ti/SiO2 substrates by HFCVD for frontier applications. [ABSTRACT FROM AUTHOR]

Electrolytic copper foil is ideal for use in the anode current collectors of lithium-ion batteries (LIBs) because of its abundant reserves, good electrical conductivity, and soft texture. However, electrolytic copper foil is prone to corrosion in electrolytes and weak bonding to the anode substance. Surface modification of copper foil is considered an effective method of improving the overall electrochemical performance of LIBs. In this study, a 5 nm thickness phytic acid (PA)-based film is constructed on electrolytic copper foil using a fast electrodeposition process (about 10 s). PA-treated copper foil (PA-Cu) displays an improved corrosion resistance in electrolytes because of a strong complexation between the PA and copper. It is found that PA-treated copper foil also bonds better with graphite particles compared with pristine copper foil. LIBs with PA-Cu foils as their current collectors exhibit enhanced cycling stability, improved capacity retention, and superior rate performance at both low and high current densities. Our study offers a novel avenue for the development of high-performance electrode current collector materials for LIBs. [ABSTRACT FROM AUTHOR]

Magnetically soft and malleable magnetostrictive (MS) alloys are highly promising as low-cost solutions for high-efficiency generation of guided waves in industrial applications and a variety of magnetostrictive patch transducers (MPTs) have been described in the literature. This work focuses on understanding the mechanisms and behaviour of soft MPTs used in the Wiedemann effect geometry, generating shear horizontal (SH) guided waves using FeCo alloy patches. MPT operation is explored in relation to patch geometry, size, magnetic field directions and guided wave wavelength. MPTs are compared with electromagnetic acoustic transducers (EMATs) and EMATs are also placed on MS and copper foil patches bonded to large glass plates for some of the measurements. Periodic permanent magnet (PPM) array EMATs operating on MPTs bonded to ferritic steel samples produced significant enhancements in the generated wave amplitude and the detected signal amplitude when compared to directly generating on the steel substrate, which primarily operates through the Lorentz mechanism. This enhanced performance was investigated and was found to be due to the magnetic fringing fields at the magnet edges. Moreover, EMAT lift-off behaviour was significantly improved when an EMAT was placed above a magnetostrictive patch, with 50 mm lift-off between the EMAT and the patch demonstrated for SH wave generation at a 22 mm nominal wavelength at a 170 kHz excitation frequency on a glass plate sample. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting is a promising alternative to produce high purity hydrogen gas as the green substitute for renewable energy. Thus, development of electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are vital to improve the efficiency of the water splitting process particularly based on transition metals which has been explored extensively to replace the highly active electrocatalytic activity of the iridium and ruthenium metals‐based electrocatalysts. In situ growth of the material on a conductive substrate has also been proven to have the capability to lower down the overpotential value significantly. On top of that, the presence of substrate has given a massive impact on the morphology of the electrocatalyst. Among the conductive substrates that have been widely explored in the field of electrochemistry are the copper based substrates mainly copper foam, copper foil and copper mesh. Copper‐based substrates possess unique properties such as low in cost, high tensile strength, excellent conductor of heat and electricity, ultraporous with well‐integrated hierarchical structure and non‐corrosive in nature. In this review, the recent advancements of HER and OER electrocatalysts grown on copper‐based substrates has been critically discussed, focusing on their morphology, design, and preparation methods of the nanoarrays. [ABSTRACT FROM AUTHOR]