Copper Substrate Research Articles

Indazole-5-amine (AIA) as competing corrosion coating to Benzotriazole (BTAH) at the interface of Cu: A DFT and BOMD case study

This study compares three organic compounds—benzotriazole (BTAH), imidazole (IM), and indazole-5-amine (AIA)—as corrosion inhibitors for copper substrates. Using Density Functional Theory (DFT) and Born-Oppenheimer Molecular Dynamics (BOMD) calculations, it identifies AIA as a promising and cost-effective alternative to the toxic BTAH. The adsorption strength on Cu(100) surfaces is ranked AIA>BTAH>IM for both neutral and deprotonated forms. These findings are supported by electronic parameter studies, including Bader charge analysis, density of states (DOS), charge density differences (CDD), and frontier molecular orbital analysis. AIA shows the best adsorption in a parallel orientation at the top site. Packing studies reveal that hydrogen bonding stabilizes the interaction energies within self-assembled AIA aggregates. Organometallic complexation studies reveal that deprotonated BTAH exhibits higher interaction energy with a single Cu atom compared to AIA when bonded through the carbon end, consistent with the findings from BOMD studies. However, on periodic Cu surfaces, AIA outperforms BTAH molecules as seen from adsorption energies. This investigation highlights AIA’s potential as a superior and more economical corrosion inhibitor for copper.

Effect of bath temperature on electroplating of nickel on a copper substrate

ABSTRACT Nickel electroplating is known to be industrially effective for enhancing various substrate properties. In the present work, nickel coatings were developed on copper substrates by electroplating using standard nickel plating solution at various electrolyte bath temperatures ranging from 40 ± 2°C to 60 ± 2°C in steps of 10°C. Energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) were used to study the composition, phase structure and morphology of the coatings. The coatings were also analysed for hardness and porosity, and process current efficiency was measured. The electrolyte bath temperature has a profound effect on the nature of the developed nickel coatings, and is observed to have an impact on the surface morphology, crystallographic direction, and hardness, as well as deposition current efficiency.

Effect of methane flow in inverse diffusion flame and surface morphology on synthesis of copper–carbon nanotubes composite

ABSTRACT In an inverse diffusion flame of fuel-rich methane–air mixture, a distinct separation between a yellow flame situated atop a high-temperature blue flame structure enabled the growth of carbon nanotubes on relatively low melting temperature copper substrates within a carbon-rich precursor environment. However, high-affinity passivation layers formation on copper prevented the diffusion of carbon precursors, rendering the growth of carbon nanotubes on copper challenging. Removal of passivation layers via sulphuric acid treatment facilitates the synthesis of carbon nanotubes within the flame. Nevertheless, the impact of sulphuric acid treatment on the surface morphology of copper, and its influence on the growth of carbon nanotubes in the presence of methane–air mixtures, remains relatively unexplored. This research investigates the effects of sulphuric acid treatment and methane–air mixtures towards the growth of carbon nanotubes on copper substrates. Application of sulphuric acid treatment yields a surface characterised by high surface area-to-volume nano-hills morphology, which enhances the adsorption of carbon atoms and leads to the growth of carbon nanotubes with lifted copper nanoparticles. The optimal growth of carbon nanotubes occurs at a specific methane flow rate, where the supply of carbon precursors aligns with the diffusion of carbon atoms and growth rate of carbon nanotubes.

Copper Foil Substrate Enables Planar Indium Plating for Ultrahigh‐Efficiency and Long‐Lifespan Aqueous Trivalent Metal Batteries

AbstractAqueous 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.

Friction and Wear Characteristics of Electrodeposited Ni‐Based Metallic Coatings on Cu‐Substrate under High‐Temperature Conditions

The Ni self‐lubricating coatings on copper substrates are deposited by electrodeposition using an aqueous electrolyte at room temperature. These coatings have the potential to improve the service life of Cu as a structural component in high‐temperature abrasion environments. A combination of low wear rate and coefficient of friction (CoF) is required in the coatings. Herein, friction and wear characteristics of the deposited Ni coatings are done by a ball‐on‐disc tribometer operated in the temperature range of 25–500 °C. The morphology and wear mechanism of tribo/transfer films are investigated using X‐ray diffraction, X‐ray photoelectron spectroscopy, and scanning electron microscopy. The CoF of Ni coating is substantially lower (CoF 0.37) at 500 °C than the Cu‐substrate, which is 0.79 at 25 °C. The Ni‐coating also reveals a low wear rate due to the formation of in situ oxides of Ni and Cu on sliding surfaces at high temperatures.

Influences of Al particles on structure and properties of Ni–Al composite coatings with nanoscale twin structure

Nickel-aluminum (Ni–Al) composite coatings containing nickel nanoscale twins have been prepared by co-electrodeposition on copper substrate. Effects of Al particles on microstructure, chemical composition, friction properties, and corrosion resistance of Ni–Al coatings were investigated. It presents an even and compact structure with granular surface that Al are evenly dispersed in pyramidal-like nickel lattice. Adding Al could alter crystal orientation, refine grains and promote strengthening effects induced by nanoscale twinning. It can enhance anti-corrosion properties and decrease the coefficient of friction (COF). The minimum COF was obtained at 10 g L−1 Al. The larger amounts and even dispersion of Al, the better corrosion resistance and the smaller COF. Increasing Al from 20 to 40 g L−1, incorporated Al in top surface rose from 20.86 to 30.13 wt%, which was larger than in cross section from 13.93 to 18.86 wt%. As the incorporated depth increased, the particle color changed from grey to dark. Nano-twins were generated around enveloped Al particles. The roughness increased as Al rose from 10 to 40 g L−1. The average roughness (Ra) was of 191–231 nm. Ni–Al-5g and Ni–Al-80g have excellent anti-corrosion features, owning the maximum Rct of 1437.2 and 1565.1 kΩ cm2, respectively, associated with the amount and distribution of Al particles, preferred orientation, grain sizes, and twinned structure. The enhanced corrosion resistance might be due to the generation of uniform, compact aluminum oxide layer by doping Al in nickel.

Enhanced insights into paired droplet evaporation dynamics on heated substrates: Unveiling the role of convection and diffusion

This study aims to examine the evaporation characteristics of single and multiple droplets on a heated substrate. By utilizing a multi-syringe pump, deionized water droplets were precisely deposited on a copper substrate, ensuring uniformity and accuracy in the experimental setup. The shadowgraph technique was instrumental in determining the droplet contact angle and volume with exceptional clarity and precision. This work numerically predicted the vapor distribution and local evaporation flux across the liquid-air interface. A critical assessment of the role of natural convection at varying substrate temperatures was performed by contrasting diffusion-only cases with those incorporating both diffusion and convection. The findings reveal that the droplet pinning motion remains unchanged across different distances between droplets and various substrate temperatures, indicating that neither vapor accumulation nor substrate temperature significantly influences the behavior of the contact line. Notably, the study identifies a reduction in the evaporation rate of closely positioned paired droplets, related to a shielding effect. However, with increasing substrate temperature, the role of natural convection was found to become more pronounced, effectively reducing the overall evaporation time for both single and paired droplets, thus facilitating a quicker evaporation process.

Thickness effect on superconducting properties of niobium films for radio-frequency cavity applications

Niobium-coated copper radio-frequency cavities are cost-effective alternatives to bulk niobium cavities, given the lower material costs of copper substrates and their operation in liquid helium at around 4.2 K. However, these cavities historically exhibited a gradual degradation in performance with the accelerating field. This phenomenon, not yet fully understood, limits the application of niobium thin film cavities in accelerators where the real-estate gradient needs to be maximized. Recent studies on niobium films deposited on copper using high power impulse magnetron sputtering (HiPIMS) technique show promising results in mitigating the performance degradation of niobium thin film radio-frequency cavities.This paper examines the effect of film thickness on the superconducting properties of niobium films deposited on copper using HiPIMS. The study provides insights into how the critical temperature, transition width, lower and upper critical fields, and critical current density vary with the film thickness. Increasing the thickness of niobium films deposited through HiPIMS is found to enhance superconducting properties and reduce densities of defects and structural irregularities in the crystalline lattice. This shows potential for enhancing overall performance and potentially mitigating the observed performance degradation in niobium thin film radio-frequency cavities. Additionally, the Ivry’s scaling relation among critical temperature, thickness, and sheet resistance at the normal state appears applicable to niobium films up to approximately 4 µm. This extends the previously confirmed validity for niobium films, which was limited to around 300 nm thickness.

Enhanced Adhesion and Resolution of Negative Photoresists on Copper Substrates with Polyglycerin-Based Methacrylate

Enhanced Adhesion and Resolution of Negative Photoresists on Copper Substrates with Polyglycerin-Based Methacrylate

Ice-Enabled Transfer of Graphene on Copper Substrates Enhanced by Electric Field and Cu2O.

Graphene films grown by the chemical vapor deposition (CVD) method suffer from contamination and damage during transfer. Herein, an innovative ice-enabled transfer method under an applied electric field and in the presence of Cu2O (or Cu2O-Electric-field Ice Transfer, abbreviated as CEIT) is developed. Ice serves as a pollution-free transfer medium while water molecules under the electric field fully wet the graphene surface for a bolstered adhesion force between the ice and graphene. Cu2O is used to reduce the adhesion force between graphene and copper. The combined methodology in CEIT ensures complete separation and clean transfer of graphene, resulting in successfully transferred graphene to various substrates, including polydimethylsiloxane (PDMS), Teflon, and C4F8 without pollution. The graphene obtained via CEIT is utilized to fabricate field-effect transistors with electrical performances comparable to that of intrinsic graphene characterized by small Dirac points and high carrier mobility. The carrier mobility of the transferred graphene reaches 9090 cm2V-1s-1, demonstrating a superior carrier mobility over that from other dry transfer methods. In a nutshell, the proposed clean and efficient transfer method holds great potential for future applications of graphene.

Ferromagnetic and supercapacitive properties of 2D Co–Ni–Gd nanoflake on copper substrate

Ferromagnetic and supercapacitive properties of 2D Co–Ni–Gd nanoflake on copper substrate

Microstructure and properties of TiB2/Cu composite coating with multi-layer structure prepared by electrodeposition

In order to improve the hardness of the copper surface, reduce its friction coefficient, and adjust the overall performance of the coating, a TiB2/Cu composite coating with multilayer structure was prepared by electrodeposition. The microstructure of the composite coating was analyzed by SEM and XRD. The microhardness and friction characteristics of the coating were tested, and the differences in the microstructures and properties of different coating structures were analyzed. Microstructure coatings with two layers (Cu + TiB2/Cu) and three layers (Cu + TiB2/Cu + Cu) were prepared on the copper substrate by electrodeposition. The TiB2 particles reduced the deposition rate of the TiB2/Cu composite coating by electrodeposition, by up to 29%. The TiB2 particles in the electrolyte increased the discharge voltage of the electrodeposition process. The content of TiB2 affected the microhardness, friction, and wear properties of the TiB2/Cu composite coating. The TiB2 particles increased the microhardness of the TiB2/Cu composite coating by 61%. The multilayer-structured coating prepared by electrodeposition could control the overall properties of the coating. The microhardness and friction coefficient of the TiB2/Cu + Cu coating were between those of the Cu and TiB2/Cu composite coatings.

Synthesis of polymeric superhydrophobic coatings of nickel stearate for excellent corrosion resistance, self-cleaning, and photodegradation

Superhydrophobic coatings (SHCs) have been widely reported for various applications; however, the practical applications of SHCs have been restricted by recurrent preparation methods, complex equipment, and low mechanical robustness. The development of a simple, low-cost, and effective superhydrophobic coating remains a challenge. Here, we reported a simple way to fabricate the SHC by using fluoropolymeric suspension of nickel stearate nanoparticles (Ni-St-NPs) on the copper and other substrates. The surface of copper coated by SHC showed a static contact angle of 161 ± 1º and a sliding angle of 2º. Scanning electron microscopy with energy-dispersive spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared spectrometer were used to determine the surface morphology, elemental content, crystal structures, chemical bonding, and structure of the SHCs. The fluoropolymeric coating of Ni-St-NPs showed excellent anti-corrosion and self-cleaning with mechanical durability and stability. Photodegradation of methylene blue (MB) and rhodamine B (RhB) dyes were done at 25 °C and obtained the degradation efficiency of 99 % and 98.1 %, respectively. The existence of self-cleaning, mechanical durability, and photocatalytic properties makes the fluoropolymer coating of nickel stearate a very promising superhydrophobic coating material for multifunctional applications.

Microstructure and excellent arc ablation resistance of Ni–8Al coating on copper substrate by high-speed laser cladding

In the case of electrical contact, copper alloys are often unable to withstand arc ablation and premature failure. To solve this issue, Ni-8wt.%Al (Ni–8Al) coatings were successfully prepared on copper substrates utilizing the high-speed laser cladding. In addition, the microstructure evolution, microhardness, electric conductivity and arc ablation resistance of the prepared coatings were investigated in detail. As a result, the achieved Ni–8Al coatings were structurally dense with good metallurgical bonding to the substrate, of which the microstructure showed a bottom-up evolution of fine sub-grain structure. Notably, the microhardness of the coating was 191.7 HV0.2, representing an increase of 82.57% compared to the substrate, and the electrical conductivity was 18.03 %IACS, approaching that of pure nickel. Additionally, the increase in ablation currents led to changes in the ablation behaviors and failure mechanisms of both the substrate and coating. At high currents, a huge arc ablation crater appeared in the center of the substrate due to the reaction force of the anode flame and the difference in surface tension between the liquid metal at the center and the edge of the molten pool. Nevertheless, the coatings showed better arc ablation resistance due to the improvement of molten pool stability during arc ablation by the in situ formed Al2O3 layer on the coating surface.

Kinetic Study of Anaerobic Adhesive Curing on Copper and Iron Base Substrates.

Anaerobic adhesives (AAs) cure at room temperature in oxygen-deprived spaces between metal substrates. The curing process is significantly influenced by the type of metal ions present. This study investigates the curing kinetics of a high-strength AA on iron and copper substrates using differential scanning calorimetry (DSC). The activation energy and kinetic parameters were determined with different empiric models, revealing that curing on copper is faster and more complete compared to iron. The findings suggest that copper ions lower the activation energy required for curing, enhancing the adhesive's performance. This research addresses the gap in understanding how metal ions affect AA curing kinetics, offering valuable insights for optimizing adhesive formulations for industrial applications.

Green synthesis, characterization and thermophysical properties of diverse molar Ag decorated GO hybrid nanofluids

The present work critically analyses the thermal characteristics of diverse molar (0.03, 0.06, and 0.09 M) Ag decorated GO hybrid nanofluids at constant 0.05 wt.%. The study broadly encompassed the synthesis, characterization, stability, thermophysical properties, reactivity, and contact angle measurements on copper substrates using varied molar Ag-GO hybrid nanofluids. The thermal impact of these hybrid nanofluids was evaluated across a temperature range of 293–333 K, encompassing thermal conductivity, specific heat, viscosity, surface tension, and density. The results illustrate that increasing the molarity of Ag over GO significantly influenced the thermal properties of the hybrid nanofluids. Notably, the most substantial improvements in thermal conductivity are observed at 333 K, reaching 30.12, 22.63, and 17.13% for 0.09, 0.06, and 0.03 M Ag-GO, respectively, compared to the base fluid. Furthermore, central composite design approach (CCD) was employed to establish correlations between the experimental and predicted thermal conductivity enhancement ratio (K-ratio) results. In conclusion, these studies underscore a promising insight that the optimizing of Ag molarity in GO hybrid nanofluids holds substantial potential for enhancing heat transfer performance across diverse heat transfer applications.

Role of Substrate on the Fractal Characteristics of Nanostructure Surfaces of Electrodeposited Nickel Thin Films

This study investigates the structure, morphological, and roughness properties of electrodeposited nickel thin films grown on different substrates, that is, silicon, copper, and gold. X‐ray diffraction analysis reveals that the Ni coatings exhibit a face‐centered‐cubic phase, regardless of the substrate used, although the texture is mainly influenced by the substrate. Atomic force microscopy images show that larger grains are obtained with gold substrates, while smaller ones are observed with copper and silicon substrates, in agreement with scanning electron microscopy. The results demonstrate that both topological and fractal characteristics of the Ni thin films are significantly influenced by the type of substrate. Statistical parameters are quantified to compare the surface morphology of the different samples. Fractal analysis reveals that the fractal dimensions of all surfaces range between 2 and 3, indicating self‐affinity. Fractal succolarity and lacunarity are measured to assess the penetration of a liquid into the surface and the distribution of gaps in the Ni film surfaces, respectively. Minkowski functionals are utilized for topological analysis to characterize the internal structure of the Ni thin films. The observed differences in roughness characteristics provide evidence that the type of substrate affects the nucleation and growth of surface features during electrodeposition.

Ultrasonic-assisted pulse electrodeposition process for producing nanocrystalline nickel films and their corrosion behavior: Competition between mass transport and nucleation

Ultrasonic-assisted pulse electrodeposition of nanocrystalline nickel (NC-Ni) coatings from Watts bath on copper substrate was investigated. Direct (DC), pulsed (PC), and pulse reversed (PRC) current electrodeposition techniques were employed to electrodeposit NC-Ni coatings in the absence and presence of ultrasound wave with a nominal power ranging from 95 W to 200 W and their surface morphology, hardness, and crystalline microstructure were compared. We observed that as the ultrasound power increases, the cathodic efficiency and the microhardness increase, whereas the crystallite size and surface roughness decrease for NC-Ni electrodeposited by the three techniques in the same way. However, the effect of pulse waveform is dominant. The finest crystallite size (24 nm) and highest hardness (585 HV) were achieved for NC Ni coatings PC electrodeposited using an ultrasound with 200 W nominal power. It is believed that the coating produced by PC and PRC techniques develops a preferential orientation in (111) and (100) planes, respectively. The application of ultrasound wave and increasing its nominal power changes the preferential orientation of all obtained coatings to (111) planes. The corrosion behavior of NC Ni coatings, as investigated by potentiodynamic polarization and electrochemical impedance spectroscopy in NaOH solution, demonstrates the effect of nanocrystalline on the passivation and corrosion resistance of NC-Ni coatings.

Density functional theory and molecular dynamics study on the growth of graphene by chemical vapor deposition on copper substrate

Chemical vapor deposition is an affordable method for producing high-quality graphene. Microscopic defects in graphene grown on copper substrates, such as five- and seven-membered rings, degrade the quality of graphene. Therefore, it is essential to study the growth process and factors affecting the quality of graphene on copper surfaces. In this study, first-principles calculations based on density functional theory show that the four-step dehydrogenation reaction of methane is endothermic, with the energy barrier for the last dehydrogenation step being relatively high. Additionally, CH forms dimers on the copper surface with a lower energy barrier and trimers with a higher energy barrier, indicating that carbon dimers are the primary precursor species for graphene growth in the early stages. Subsequently, in molecular dynamics simulations, the analytical bond-order potential based on quantum mechanics is employed. The results reveal that the growth of graphene on the copper surface involves the diffusion and gradual nucleation of carbon dimers in the early stages, the gradual enlargement of graphene domains in the intermediate stages, and the gradual merging of graphene domain boundaries in the later stages. Moreover, the growth of graphene on the copper substrate follows a self-limiting growth mode. Increasing the deposition interval of carbon atoms and reducing the carbon atom deposition velocity contribute to enhancing the quality of graphene grown on the copper substrate.

Atomic simulation study on the effect of defects on nano-cutting mechanism of single crystal copper

Due to the high surface roughness of the parts produced by additive manufacturing (AM), the subsequent mechanical processing is required. The combination of additive manufacturing and micro/nano processing is the development trend of hybrid manufacturing in the future. In this work, the molecular dynamics simulation is used to study the effect and mechanism of different types of defects on copper cutting performance, including pore, Cr precipitate and diamond inclusion. The results show that the presence of defects leads to a decrease in the quality of the machined surface, while pore and diamond inclusion could lead to the appearance of deep holes on the machined surface. The phenomenon of sticking knife caused by stress concentration and high temperature at the tool tip is observed during the simulation in the model with Cr precipiate. The addition of defects causes a change in the horizontal cutting force. The highest force emerges during the simulation in the model with diamond inclusion. Defects in the copper substrate could reduce surface quality. Precipitate and inclusion could increase the stress near the tool so as to exacerbate tool wear and reduce tool life. Therefore, it’s necessary to decrease the number of defects in the matrix and to improve its cutting resistance.