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Electroforming is a promising manufacturing process for producing precise and customized metal components, making it suitable for personalized and small-batch production. Combining electroforming with fused deposition modeling (FDM)-produced molds offers a cost-effective and adaptable method for fabricating complex metal parts. Recent studies have demonstrated its ability to create intricate multi-level and free-form geometries with significant thicknesses. This study focuses on examining how electrode placement influences copper deposition during electroforming in FDM molds. A simulation model is developed and utilized as a tool to visualize copper growth and evaluate the impact of various electrode configurations on deposition uniformity and accuracy. Experimental validation supports the simulation findings, leading to the development of practical design guidelines for optimal mold design and electrode placement. This research contributes to advancing electroforming in 3D-printed molds as an efficient and scalable solution for producing high-quality, customized metal components. [ABSTRACT FROM AUTHOR]

An innovative approach for metal electroforming is presented, exemplified with proof-of-concept geometries and illustrated with an industrial application. The proposed production chain hybridizes 3D polymer printing and nickel electroplating for the design-controlled forming of metals within fused deposition modelled contours or patterns, which provide a selective functionalization of the substrate for metal deposition on demand. Applying the developed process, Ni electrodes for streamer discharge plasma generators are structured. These components stand out for their needle-like details, required for promoting streamer discharge phenomena, which would be challenging to obtain employing traditional milling processes. Current capabilities, main challenges and foreseen research directions, for this novel hybrid 3D printing and electroplating process and for its industrial applications, are discussed. Overall, the described process contributes to the already fruitful connections among additive manufacturing technologies and metal electrodeposition procedures, providing an interesting route towards accessible and straightforward electroforming of large components and structures. [ABSTRACT FROM AUTHOR]

[Display omitted] Due to the uncontrollable growth of lithium dendrites and the considerable volume change of lithium during cycling, the practical application of lithium metal batteries has stalled. The current collector with a 3D structure has been demonstrated to effectively inhibit the growth of lithium dendrites and mitigate the volume change of lithium, which can effectively promote the practical application of lithium metal batteries. The conventional electrodeposition method for constructing 3D structures on the surface of a copper current collector is prone to forming dendritic structures with sharp surfaces. However, the dendritic structure is susceptible to the tip effect, resulting in inhomogeneous lithium deposition. In this study, PAA molecules are adsorbed on the surface of copper to hinder and disperse its growth during electrodeposition, optimizing its growth mode. Thus, mulberry-like copper with a biomimetic structure is prepared on the surface of copper foil (M-CF). The mulberry structure not only provides additional electrochemically active sites and robust conductive frameworks for lithium deposition, it also efficiently mitigates the electric field concentration at the 3D structure's tip, optimizes lithium-ion transport flux, suppresses the growth of lithium dendrites. As a result, the M-CF anode is capable of stable Li plating/stripping over 500 cycles with a high average CE of 98.1 %. The assembled symmetrical battery is stably cycled over 1600 h at a low voltage hysteresis of 11 mV. The full cells paired with M-CF-Li-6 (Li: 6 mAh cm−2) anodes and LTO cathodes stably cycle more than 500 cycles, and the capacity retention rate is 95.3 %. [ABSTRACT FROM AUTHOR]

The current electrolytes used for metal electrodeposition mostly use aqueous solutions that limit the range and quality of possible coatings. Also, some of these solutions may contain toxic and corrosive chemicals. Thus, the importance of ionic liquids (ILs) and deep eutectic solvents (DES) becomes clear, as they can be used as green non-aqueous electrolytes for the electrodeposition of a range of reactive metals that are impossible to deposit in aqueous solutions and for the improved electrodeposition of metals that are deposable in aqueous solutions. This paper presents some examples of electrodeposition in ILs and DESs that are considered specific processes. Aluminum, as an active metal that it is impossible to electrodeposit in aqueous solution, was electrodeposited from a chloroaluminate IL. Moreover, the electrodeposition of Al was carried out in open air using a novel approach. Chromium was electrodeposited from a DES containing the environmentally friendly form of Cr (III) instead of toxic Cr (VI). Magnesium alloys, as water-sensitive substrates, were electroplated in an air and water-stable DES. Also, this paper discloses, for the first time, the procedure of pretreatment of Mg alloys for successful electroplating. [ABSTRACT FROM AUTHOR]

Electrodeposition is widely used in metallurgy, chemical industry, materials and other fields. Its significant advantages include high precision, a wide range of applicability and controllability. With in-depth theoretical and experimental research, electrodeposition technology has achieved remarkable development. However, when pursuing higher performance of the deposited layer, problems such as large deposited grains, poor surface flatness, long deposition time, high energy consumption, hardness, wear resistance and corrosion resistance have occurred. As well as the serious phenomenon of agglomeration of composite particles in composite electrodeposition, these problems restrict the popularization and application of electrodeposition technology. Addressing the need for rapid deposition to meet growing production demands and enhancing deposition quality are current focal points in electrodeposition technology development. In metallurgy, new methods and theories are constantly emerging, and unconventional metallurgy technologies different from those of the conventional metallurgical industry have flourished. The current external fields used in the electrodeposition process of hydrometallurgy mainly include ultrasound field, magnetic field, plasma and laser. This paper introduced the mechanism of different external fields to strengthen the electrodeposition process and pointed out the applications, current problems and development trends of ultrasound, magnetic field, plasma and laser in metal electrodeposition. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Electrolytic manganese metal (EMM) produced from recyclable resources has recently gained increasing attention due to the scarcity of high-quality manganese natural resources and its broad range of applications. This review has summarised recent progress in manganese recovery techniques, including pyrometallurgy and hydrometallurgy. It has also critically assessed the processes and mechanisms involved in manganese electrodeposition for the Mn chloride- and Mn sulphate-based systems, with a major focus on electrode reactions and Mn nucleation growth. The key optimisation factors influencing manganese electrodeposition, such as electrolytes, power consumption, additives, cell structures, and electrode materials, were analysed, with particular attention to their impact on current efficiency, specific energy consumption, and product quality. The recent research directions were also highlighted to address practical challenges and enhance the sustainability of the EMM process, which mainly includes improving the ecological outcomes and reducing both the operating and investment costs. Promising strategies for the simultaneous production of EMM and electrolytic manganese dioxide (EMD) were also identified, which mainly comprised applying membrane technology, electrodeposition from ionic liquids, recycling and reusing waste materials, and exploring hybrid techniques. The results of this study showed that the prospective optimisation approaches for EMM are mainly driven by the need to enhance efficiency, reduce costs, and improve product quality through sustainable technological advancements. This review can be used as a comprehensive guide for manganese electrodeposition approaches for both practical and scientific research communities. [ABSTRACT FROM AUTHOR]

Electrocatalysts for high-performance oxygen evolution reaction (OER) have suffered complex synthesis and activation processes, low electrical conductivity, and weak interactions with electrode substrates. To overcome these drawbacks, this study introduces metal dissolution electrodeposition (MDE) as a novel solution for fabricating OER catalysts. MDE involves the dissolution of a nickel substrate in an electrolyte containing Fe3+ ions, followed by the redeposition of the dissolved ions. Fe3+ delivers stable deposition of Ni2+ and Fe2+ due to their low reduction potential, enhancing adhesion of the catalyst with etched Ni substrate. Additionally, MDE allows the formation of abundant amorphous NiOOH phases, which can partially crystallize during activation through Fe de-intercalation, effectively forming Fe-integrated NiOOH. The optimized Fe-γ-NiOOH catalyst synthesized via MDE demonstrated superior OER performance, with a low overpotential of 257 mV at a current density of 100 mA/cm2, a Tafel slope of 49.74 mV/dec, a charge transfer resistance of 551 mΩ, and a high active surface area of 13.23 mF/cm2. Notably, material prepared by MDE shows an overpotential improvement of approximately 50 mV compared to the 306 mV at 100 mA/cm2 achieved by conventional electrodeposition (CE) methods. These findings highlight the potential of MDE in developing high-performance OER catalysts, eliminating the need for nickel precursors. • MDE method dissolves metal ions from a substrate and re-deposits them. • MDE overcomes the weak interactions of electrocatalysts with the substrate. • Amorphous NiOOH from MDE facilitates Fe integration during the activation process. • Fe-γ-NiOOH from MDE shows superior OER performance with 257 mV at 100 mA/cm2. • Material prepared by MDE has lower overpotential compared to CE. [ABSTRACT FROM AUTHOR]

Developing efficient and affordable electrocatalysts for alkaline water electrolysis (AWE) for example in the hydrogen evolution reaction (HER) is crucial for sustainable energy sources and other applications. Herein, a new approach of a facile, one-step electrodeposition method has been adopted to fabricate an ultrathin NiMoO 4 layer at the in-situ functionalized graphite felt (FGF) substrates. The as-synthesized NiMoO 4 @FGF (denoted as Ni 1 :Mo 1/2 @GF) electrode exhibits distinguished performance towards HER with a markedly low overpotential (η) of 17 mV at a current density of 10 mA cm−2 with a low Tafel slope of 37 mV dec−1. This is a tremendously high performance compared with that of the Ni(OH) 2 @FGF (denoted as Ni 1 :Mo 0 @GF) electrode without Mo ions (η = 158 mV @10 mA cm−2 and Tafel slope of 143 mV dec−1). In addition, the NiMoO 4 @FGF electrode exhibits impressive stability, retaining a current density of 10 mA cm−2 throughout 24 h of continuous electrolysis and for continuous operation of 98 h at a current density of 100 mA cm−2. This work elucidates an expeditious procedure for the simple design of high-performance electrocatalysts aimed at augmenting HER, by distributing NiMoO 4 over the in-situ FGF fibers which possess high electronic and ionic conductivity. [Display omitted] • NiMoO 4 @FGF catalyst was electrochemically fabricated. • Surface hydrophilicity enhanced happened during metals electrodeposition. • The NiMoO 4 @FGF displayed 17 mV at −10 mA cm−2 with a low Tafel slope of 37 mV dec−1. • The ratio between Ni to Mo ions is the key for the intrinsic catalytic activity and stability. [ABSTRACT FROM AUTHOR]

This study explores the impact of metallic shells by electroforming method on the mechanical behavior of thermoplastic polyurethane (TPU)-based lattice structures. First, the TPU lattice structures were printed by additive manufacturing technique. Then layers of Ni and Cu as a thin shell were dressed on the TPU lattice structures in the electroforming baths of Ni and Cu solutions. Finally, uniaxial compression tests achieved on the samples. Results demonstrated substantial enhancements in mechanical performance attributable to these metallic coatings. Notably, the Ni-coated lattice structure (Ni-LS) exhibited a peak yield strength of 4.55 MPa, marking a 1.08-fold improvement over the Ni-Cu-LS structures and a 1.35-fold increase relative to the Ni-Cu-Ni-LS variant. Furthermore, the energy absorption density of the coated structures was elevated by nearly sixfold compared to the uncoated TPU lattice, with multi-layer coatings providing additional gains. These results underscore the potential of Ni and Cu-coated TPU lattices to deliver exceptional strength-to-weight ratios and enhanced energy absorption capabilities. [ABSTRACT FROM AUTHOR]

ABSTRACT A major effort in technological development was conducted during the 19th century. The polychrome surfaces of the metal parts of a corner cabinet, a torch vase, an “elephant” vase, and a candelabra pair designed by Emile Reiber between 1874 and 1878 for the Christofle & Cie Company were investigated on site by means of noninvasive Raman, FTIR, and X‐ray fluorescence spectroscopy after examination under white light at different magnifications and under UV illumination. Despite the low thickness of the patinas (a few tens of microns) different (electro)chemically formed phases were identified in these layers (Cu2O, Ag2S, CuS or Cu2S, and sulfates). Residues of organic conservation products are identified by FTIR reflectance. The results are compared with the information available in the patents filed by the company as well as other written sources from that period. The pigments and opacifiers (Naples yellows, lead arsenates, fluorite, spinels, cassiterite, and chromates), and the vitreous matrices of the cloisonné enamels of the objects above are identified and testify to the deliberate combination of European and Asian enameling techniques. [ABSTRACT FROM AUTHOR]

In this study, oxygen‐rich TiOy and TiOx layers are intentionally designed to have different oxygen compositions, functioning as an overshoot suppression layer (OSL) and oxygen reservoirs. Furthermore, by natural oxidation reactions occurring between the TiOy/TiOx/Al2O3 switching layer and the Pt/Al top electrode, an additional AlOy layer can be induced to act as an additional OSL. The proposed annealing process accelerates the oxidation reaction of AlOy/TiOy OSLs, thereby enhancing the self‐compliance feature of devices. Moreover, the ultrathin AlN serves as an oxygen barrier layer (OBL) that inhibits the movement of oxygen ions at the interface between the Al2O3 layer and the Pt/Ti bottom electrode. The optimized devices are tested by DC sweep and pulses for neuromorphic computing systems. To realize biological synapse characteristics, several key synaptic memory plasticities are proposed. Finally, a 24 × 24 crossbar array based on the 0T‐1R structure, incorporating optimized AlOy/TiOy OSLs and OBL via the annealing process, is characterized. During the electroforming step, all specified target cells (marked with the letters "ESDL") achieved self‐compliance at low current levels without experiencing hard‐breakdown failures or interference among neighboring cells. The successful array performance is demonstrated by the accurate tuning of target weights. [ABSTRACT FROM AUTHOR]

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The metal–insulator–metal sandwich structures with the end surface of the insulator film (insulating slit) open to the gas environment were manufactured using thin-film technology. Electroforming, which consists of applying voltage according to a specific algorithm, causes the formation of conductive phase particles due to the destruction of organic molecules adsorbed on the open surface of the insulator by electron impact during the electric current flow. The accumulation of particles leads to the growth of a linked conductive cluster (a conductive carbon medium) and the formation of a conductive nanostructure with the memristor properties in the insulating slit. The practical use of such structures is limited by the low efficiency of electroforming: relatively long process times (on the order of several seconds) and an increased probability of electrical breakdown of the structure. Several ways to improve the efficiency of the electroforming process are presented. Firstly, the use of the correct voltage polarity for the open TiN–SiO2–W sandwich structure, where W should be the anode, which sharply reduces the probability of breakdown. Secondly, the use of two-stage electroforming: first, the formation of conductive channels in an "oil-free" vacuum after annealing in it, when the voltage can be applied in parallel to a large number of structures, and then in an "oil" vacuum containing organic molecules at significantly lower voltages and exposures. Thirdly, replacing the tungsten anode with a molybdenum one, which, while maintaining the advantages of tungsten, leads to an increase in the initial conductivity of the open sandwich structure (TiN–SiO2–Mo) by several orders of magnitude, and, therefore, to an acceleration of the electroforming process and a decrease in the applied voltages. [ABSTRACT FROM AUTHOR]

In this study, a portion of an ultra-light polymeric sandwich panel was produced by additive manufacturing with a dimension of 25 × 25 × 37 mm as a precursor. Then, the precursor was covered with a thin-walled copper through electroforming deposition as a portion of a copper sandwich panel. The weight of the polymeric sandwich panel increased from 2–4 g to 9–13 g for the copper sandwich panel during the electroforming process. Compressive strength and energy absorption density of the polymeric and the copper sandwich panels with open-cell cores measured for 4, 5 and 6 PPI. The results shown that the ultra-light polymeric and copper sandwich panels with 6 PPI have the best mechanical performance in terms of yield stress, energy absorption density and energy absorption efficiency. Moreover, the abovementioned characteristics are 0.09 MPa, 0.11 MJ. m − 3 and 80% for the polymeric sandwich panels, and 1.74 MPa, 0.98 MJ. m − 3 and 70% for the copper sandwich panels, respectively. Therefore, the addition of 9.01 g copper as a reinforcing around the core's polymeric ligaments caused an increase in the yield stress for 20 times and in the energy absorption density for 9 times. Comparing to Ashby diagram, and previous studies, the sandwich panel portions of this study could develop the industry of sandwich panels by using the metallic shells as a reinforcement to ultralight polymeric sandwich structures. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐metal batteries (AZMBs) represent a promising frontier in battery technology, offering sustainable and safe alternatives to traditional non‐aqueous batteries. Despite their potential, understanding the kinetics of zinc electrodeposition—a critical factor in AZMB performance—remains underexplored. Utilizing voltammetry on ultramicroelectrodes, we investigate how scan rate influences key processes of nucleation and growth during Zn2+ electrodeposition. The findings highlight the efficacy of the Butler‐Volmer formulation in capturing electron‐transfer kinetics, contrasting with complex electron transfer kinetic models used for non‐aqueous battery chemistries. We clearly demonstrate that there is a strong dependence of scan rate on the measured value of kinetic parameters (exchange current). To accurately probe the charge transfer kinetics, it is essential to apply fast scan voltammetry to decouple the influence of mass transfer, ensuring that the measured current is independent of the scan rate. Furthermore, by studying a model electrolyte additive, the intricate balance between charge transfer and mass transfer dynamics is unveiled, and this information is crucial for enhancing the stability of zinc metal anodes. These insights pave the way for developing advanced electrolyte and current collector formulations, promising enhanced cyclability and sustainability in zinc metal batteries. [ABSTRACT FROM AUTHOR]

Temperature serves as a pivotal factor influencing information transmission and computational capacity in neurons, significantly affecting the function and efficiency of neural networks. However, the temperature dependence of VO2-based artificial neuron, which is one of the highly promising artificial neurons, has been hardly reported to date. Here, high-performance VO2 devices with NDR features are prepared by rapid annealing and electroforming processes. We constructed VO2-based artificial neurons with output properties similar to those of biological neurons on the basis of the Pearson–Anson oscillation circuit. The temperature-dependent behavior of VO2 neurons was fully investigated. Increasing temperature leads to a decrease in the peak-to-peak value of the output spikes of VO2 neurons. The spike period of VO2 neurons remains relatively stable near room temperature, but it decreases as the temperature reaches above 26 °C. These temperature-dependent features of VO2 neurons are similar to the ones of biological neurons, suggesting a natural advantage of VO2-based artificial neurons in mimicking biological neural activity. These findings contribute toward comprehending and regulating the temperature-dependent behavior of artificial neurons based on Mott memristor. [ABSTRACT FROM AUTHOR]

In the current work, CeO 2 nanoparticles were embedded in Ni-W alloy matrix by pulse electrochemical deposition on copper substrate to optimize their microstructure and corrosion resistance. The effects of CeO 2 concentration and deposition time on Ni-W/CeO 2 composite coating were investigated for optimized structure and improved corrosion resistance. The composite coatings present nodular-like surfaces with dense and compact growth profiles, containing 63.03–67.88 wt% Ni, 28.73–31.87 wt% W and 0.25–8.24 wt% Ce. The content of incorporated CeO 2 in coatings increased with the increase of CeO 2 concentration in electrolyte. The addition of CeO 2 particles has refined the grains of the prepared coating. The surface became rougher with the extension of electrodeposition time. Ni-W/CeO 2 composite coating electrodeposited at 10 g L−1 CeO 2 for 60 min possessed the highest corrosion resistance, indicating enhanced corrosion protection and long-term stability. This premium coating can be applied in harsh environments to prolong the lifespan of machinery, equipment, and parts in marine, vehicle, aerospace, and chemical industries. [ABSTRACT FROM AUTHOR]

Devices made of amorphous thin films of the prototypical Mott‐insulator chromium‐doped V2O3 show a threshold and negative differential resistance effect after an electroforming step. Here, it is demonstrated that this effect is caused by the formation of a crystalline filament, in which a thermal runaway effect can occur. A compact model is developed that can describe the switching behavior as well as its inherent variability. The influence of the doping concentration and oxygen stoichiometry on the switching behavior is characterized and by fitting the model to the experimental data, the underlying physical changes are extracted. [ABSTRACT FROM AUTHOR]

Devices made of amorphous thin films of the prototypical Mott‐insulator chromium‐doped V2O3 show a threshold and negative differential resistance effect after an electroforming step. Here, it is demonstrated that this effect is caused by the formation of a crystalline filament, in which a thermal runaway effect can occur. A compact model is developed that can describe the switching behavior as well as its inherent variability. The influence of the doping concentration and oxygen stoichiometry on the switching behavior is characterized and by fitting the model to the experimental data, the underlying physical changes are extracted. [ABSTRACT FROM AUTHOR]

Interest in metal electrodeposition for synthesizing customized nanomaterials has resurged, particularly for applications such as sensors and fuel cells. The present study involved the synthesis of ZnSe nanoparticles (via hydrothermal method) while polypyrrole and novel composite Ppy@ZnSePpy@Ppy (via sequential electrodeposition technique) on a glassy carbon (GC) electrode and their physiochemical, electrochemical, and operando spectro-electrochemical characterizations towards oxygen evolution reaction (OER). Results indicated that ZnSe nanoparticles are well embedded within the Ppy layers and during OER the composite electrocatalyst approached 398 mV at 10 mA cm−2 and exhibited Tafel value (b ∼ 75 mV dec−1) with ECSA (0.03) which shows better results than other two. In addition, the operando spectro-electrochemical spectra of the composite revealed the significant generation of active intermediate oxygen species of selenium and Zn2+. The important feature of the current work is the disclosure of Se's questionable role and species involved in OER found to be Se4+. [Display omitted] • State of art Ppy@ZnSePpy@Ppy composite & its physicochemical characterization has been reported. • Electrodeposition method used for synthesis of composite. • First time operando spectroelectrochemical study was carried out to study OER of Ppy@ZnSePpy@Ppy. • The ambiguous role of Se has been revealed. • As Synthesized composite has shown better candidature towards OER. [ABSTRACT FROM AUTHOR]

Pulsed current has proven to be a promising alternative to direct current in electrochemical deposition, offering numerous advantages regarding deposit quality and properties. Concerning the electrodeposition of metal alloys, the role of pulsed current techniques may vary depending on the specific metals involved. We studied an innovative tin–ruthenium electroplating bath used as an anti-corrosive layer for decorative applications. The bath represents a more environmentally and economically viable alternative to nickel and palladium formulations. The samples obtained using both direct and pulsed currents were analyzed using various techniques to observe any differences in thickness, color, composition, and morphology of the deposits depending on the pulsed current waveform used for deposition. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the resistive switching (RS) behavior of Cu/ZnO/ITO devices subjected to various rapid thermal annealing (RTA) temperatures under vacuum. Current–voltage characteristics reveal that following the application of a positive electroforming voltage, both unannealed ZnO films and those annealed at 200 °C exhibit bipolar RS, consistent with the electrochemical metallization mechanism (ECM). However, films annealed at higher temperatures exhibit RS with both positive and negative electroforming threshold voltages and coexistence of switching in both polarities. Ultimately, these films display RS behavior aligned with the valence change mechanism (VCM), dominated by a negative electroforming voltage and RS on the negative bias side, while positive electroforming voltage and RS vanish for films annealed at 600 °C. Curve fitting analysis was conducted for Schottky emission (SE), space-charge limited current, and Poole–Frenkel (PF) emission mechanisms, with SE and PF emission providing better fits. These results demonstrate the tunability of ECM and VCM RS modes and the polarity of the forming bias, underscoring the potential of vacuum RTA in advancing ZnO-based memory device development. [ABSTRACT FROM AUTHOR]

This paper is a 'follow-on' from a paper previously published in this journal dealing with the laboratory to pilot scaling up approach using Industry 4.0 manufacturing methods. In particular, the paper reports a strategy for developing a model for the electroforming of nickel from a sulphamate electrolyte at laboratory scale which could subsequently provide an educated approach for transferring the process to a larger scale. At the laboratory scale, a rotating disc electrode assembly was used, which is a standard instrument to determine electrochemical parameters. Thereafter, small scale nickel discs were electroplated using this equipment, and a model of this process was developed and validated against those experimental results. These parameters were then used to actually produce electroforms in a prototype, 18 L tank system. Cross-validation between practical experiments and simulations followed which allowed for fine-tuning the model until it was consistently predicting the real process results within an acceptable error. Overall, it was found that a secondary current distribution model could be used for reasonably accurate description for the electroforming process, and could provide a quick virtual tool at a production facility. [ABSTRACT FROM AUTHOR]

Copyright of Micronanoelectronic Technology is the property of Micronanoelectronic Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nanoscale materials often undergo structural, morphological, or chemical changes, especially in solution processes, where heterogeneity and defects may significantly impact the transformation pathways. Liquid phase transmission electron microscopy (TEM), allowing us to track dynamic transformations of individual nanoparticles, has become a powerful platform to reveal nanoscale materials transformation pathways and address challenging issues that are hard to approach by other methods. With the development of modern liquid cells, implementing advanced imaging and image analysis methods, and strategically exploring diverse systems, significant advances have been made in liquid phase TEM, including improved high-resolution imaging through liquids at the atomic level and remarkable capabilities in handling complex systems and reactions. In the past more than a decade, we spent much effort in developing and applying liquid phase TEM to elucidate how atomic level heterogeneity and defects impact various physicochemical processes in liquids, such as growth, self-assembly of nanoparticles, etching/corrosion, electrodeposition of alkali metals, catalyst restructuring during reactions, and so on. This article provides a brief review of the liquid phase TEM study of nanoscale materials transformations, focusing on the growth of nanomaterials with distinct shape/hierarchical structures, such as one-dimensional (1D) growth by nanoparticle attachment, two-dimensional (2D) growth with nanoparticles as intermediates, core-shell structure ripening, solid-liquid interfaces including those in batteries and electrocatalysis, highlighting the impacts of heterogeneity and defects on broad nanoscale transformation pathways. [ABSTRACT FROM AUTHOR]

BACKGROUND: This work studied the treatment of a synthetic sphalerite acid mine drainage (AMD). The treatment was carried out by means of a previous concentration stage using electrodialysis, followed by electrodeposition using a bioelectrochemical system (BES). RESULTS: The best concentration results were obtained when operating the electrodialysis at 8 V and at a diluate/concentrate volume ratio of 3. This treatment yielded a concentrate fraction of about 25% of the volume and a clear fraction of about 75% of the volume. The concentrated fraction was treated in a BES for the electrodeposition of the metal contained. By operating a microbial fuel cell (MFC), the spontaneous reactions took place and, in 2 days, all the Fe3+ was reduced to Fe2+; then, all the Cu2+ was electrodeposited as pure Cu0 in about 8 days. The maximum current density attained in this stage was 0.1 mA cm−2 and the maximum power was 0.05 W cm−2. Then, a subsequent operation of a microbial electrolysis cell (MEC) allowed for the simultaneous recovery of the Fe2+, Ni2+, Zn2+, and Cd2+ as a mixed metal mass. CONCLUSION: The electrodialysis yielded a clear effluent representing 75% of the total volume and a concentrated effluent accounting for 25%. It was possible to treat the concentrated effluent in an MFC, recovering pure Cu0 with a net electricity generation. The non‐spontaneous metal reductions were subsequently accomplished by means of MEC, the electricity requirements being lower than those in the case of the raw AMD due to the higher mass transfer rate and the reduction of the Ohmic loses. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Dimensional Stable Anode (DSA) is a promising candidate for the electrodeposition of nonferrous metals. However, the industrial applications of DSA are limited due to the propensity of Ti substrate to easily undergo passivation. Theoretically analyses shows that TiMn2 has better corrosion resistance in highly acidic and strongly polarized environments, making it an ideal middle‐layer for DSA anodes. To investigate the corrosion resistance of TiMn2, N‐doped TiMn2 (N‐TiMn2) is prepared by the high‐temperature nitriding method. The high charge transfer resistance (Rpo) of N‐TiMn2 reduces the electron transfer ability of its surface and improves the chemical stability. Scanning electron microscopy, X‐ray diffraction, and Raman spectroscopy show that Ti/N‐TiMn2 can better inhibit the oxidation of Ti during electrochemical corrosion while forming a more stable α‐MnO2 film. The Ti/N‐TiMn2/MnO2 anode is prepared, and the theoretical lifetime reaches 541.5 days in zinc electrodeposition simulation experiments. This middle layer provides a new idea for developing the oxygen evolution anode in the electrowinning of nonferrous metals. [ABSTRACT FROM AUTHOR]

This article presents a study on influence of Copper Concentration Electrolyte (CCE) and voltage on deposition rate of electroformed Conductive Acrylonitrile Butadiene Styrene (CABS) produced through Fused Deposition Modeling. Additive manufacturing is widely recognized as a rapid production technology. In this research, copper electroforming was selected as subsequent treatment following additive manufacturing. The novelty lies in implementation of pre-treatment process involving electroforming. The pre-treatment process employs carbon conductive paint to render the ABS part conductive. The copper electroforming process involves the use of variable parameters such as electrolyte content of (100, 150, and 200 gram CuSO4 and 50 ml H2SO4) in 1 liter H2O, voltage (1, 2, and 3 Volts), and time (2, 4, 6 and 8 hours). The variables under observation include the copper deposition rate and the microstructure. The analysis of research based on Kruskal-Wallis test. The difference in electrolyte copper concentration and the coating time does not provide significant differences, while the duration of electroforming affects the thickness of the copper deposit. Furthermore, the concentration of copper electrolyte influences the solution's conductivity, at high concentrations leading to improve conductivity and consequently facilitating a fast deposition rate. The difference in voltage has a significant effect on the deposition rate and microstructure. [ABSTRACT FROM AUTHOR]

Transition metal coordination polymers (TM‐CP) are promising inexpensive and flexible electrocatalysts for oxygen evolution reaction in water electrolysis, while their facile synthesis and controllable regulation remain challenging. Here we report an anodic oxidation‐electrodeposition strategy for the growth of TM‐CP (TM=Fe, Co, Ni, Cr, Mn; CP=polyaniline, polypyrrole) films on a variety of metal substrates that act as both catalyst supports and metal ion sources. An exemplified bimetallic NiFe‐polypyrrole (NiFe‐PPy) features superior mechanical stability in friction and exhibits high activity with long‐term durability in alkaline seawater (over 2000 h) and anion exchange membrane electrolyzer devices at current density of 500 mA cm−2. Spectroscopic and microscopic analysis unravels the configurations with atomically distributed metal sites induced by d‐π conjugation, which transforms into a mosaic structure with NiFe (oxy)hydroxides embedded in PPy matrix during oxygen evolution. The superior catalytic performance is ascribed to the anchoring effect of PPy that inhibits metal dissolution, the strong substrate‐to‐catalyst interaction that ensures good adhesion, and the Fe/Ni−N coordination that modulates the electronic structures to facilitate the deprotonation of *OOH intermediate. This work provides a general strategy and mechanistic insight into building robust inorganic/polymer composite electrodes for oxygen electrocatalysis. [ABSTRACT FROM AUTHOR]

The tensile properties of the electroforming deposits with traditional high-concentration sulfate copper are poor, and its tensile strength is only approximately 180 MPa. To improve the mechanical and physical properties of electroforming copper, the influences of copper sulfate concentrations and current densities on the tensile properties of free beads-friction-assisted electroforming copper are investigated. In the experiment, low copper sulfate concentrations of 40, 80 and 120 g/L are selected, and ceramic beads are used to grind the surface of the cathode. The results show that when reducing the copper sulfate concentration or increasing the current density, the tensile strength and elongation ratio can be improved. The electroforming deposit of highest tensile property is obtained with copper sulfate concentration of 80 g/L and current density of 4 A/dm2, and the microhardness is 146.3 HV, the tensile strength is 308.5 MPa and the elongation ratio is 19.6%. Compared with the result of traditional high-concentration sulfate electroforming copper, the tensile strength increases by approximately 70%. Moreover, the fracture section appears dimple fracture, approving the electroforming copper is uniform and dense in microstructure. However, for 40 g/L ultra-low-concentration sulfate electroforming copper, the cathode limit current density is approximately 3 A/dm2, and when the current density increases to 4 A/dm2, the excessive current density increases the degree of concentration polarization. The hydrogen evolution is so serious that the electroforming deposit undergoes hydrogen embrittlement fracture, so the tensile properties decrease. The microhardness is 102.3 HV, the tensile strength is only 130.4 MPa and the elongation ratio is 6.1%. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER), as a pivotal half-reaction, significantly hinders the advancement of energy conversion efficiency. Metal electrodeposition on catalysts has been demonstrated to effectively enhance the HER reactivity. Here, Ni3S2–Fe–Ni with a multilayer structure was obtained by the electrodeposition of Ni3S2 with dopants Fe/Ni, in which a number of active sites were achieved and the intrinsic conductivity of the catalyst was well improved. Elemental analyses revealed the multilayer structure consisting of Ni3S2, NiS, and Fe. The Ni3S2–Fe–Ni catalyst exhibited impressive electrochemical performance due to optimization of its structure with the overpotentials of the HER and OER of only 83 and 190 mV. Notably, at a higher current density of 100 mA cm−2, the overpotentials for the HER and OER are only 339 and 365 mV. As a bifunctional electrocatalyst, its total splitting voltage was only 1.55 V. The catalysis performance remained nearly unchanged even after 48 h of stability testing. Finally, density functional theory (DFT) calculations revealed that the potential barriers in each reaction step of the OER are evenly distributed, and optimizing the Ni3S2 structure with iron and nickel atoms reduced the reaction energy barriers during the electrochemical process, improving the OER/HER performance. [ABSTRACT FROM AUTHOR]

Electrodeposition of abundant metals to fabricate efficient and durable electrodes indicate a viable role in advancing renewable electrochemical energy tools. Herein, we deposit Co9S8‐Ag‐Ni3S2@NF on nickel foam (NF) to produce Co9S8‐Ag‐Ni3S2@NF as a exceedingly proficient electrode for oxygen evolution reaction (OER). The electrochemical investigation verifies that the Co9S8‐Ag‐Ni3S2@NF electrode reveals better electrocatalytic activity to OER because of its nanoflowers′ open‐pore morphology, reduced overpotential (η10=125 mV), smaller charge transfer resistance, long‐term stability, and a synergistic effect between various components, which allows the reactants to be more easily absorbed and subsequently converted into gaseous products during the water electrolysis route. Density functional theory (DFT) calculation as well reveals the introduction of Ag (222) surface into the Co9S8 (440)‐Ni3S2 (120) structure increases the electronic density of states (DOS) per unit cell of a system and increases the electrocatalytic activity of OER by considerably lowering the energy barriers of its intermediates. This study provides the innovation of employing trimetallic nanomaterials immobilized on a conductive, continuous porous three‐dimensional network formed on a nickel foam (NF) substrate as a highly proficient catalyst for OER. [ABSTRACT FROM AUTHOR]

A new eddy current sensor with planar coils designed for noncontact distance measurement was applied in the inter electrode gap detection in the electrochemical machining (ECM). The sensor consists of two micro electroforming planar coils (driver coil and sensitive coil) stacked on the magnetic core. The magnetic model of the detection principle was built, and a new micro motion system was developed as a test and machining platform also. The size of the sensor was: Φ5 mm × 1.5 mm. The results show that the sensor is compact enough to nondestructively assess the electrode gap distance and could be easily integrated into a tool cathode for real-time electrolytic machining gap detection. [ABSTRACT FROM AUTHOR]

The electrodeposition of copper (Cu), silver (Ag), and their alloys has been a subject of interest since the 19th century. Primarily due to their exceptional features such as good mechanical hardness and electrical conductivity, high resistance to corrosion, and electromigration, Cu–Ag electrodeposits continue to be investigated and developed to improve their properties for different applications. This paper reviews the state of the art in the field of electroplated Cu–Ag alloys in an aqueous solution, with particular emphasis on the observed properties and variety of electrochemical processes used to produce high-quality materials. Moreover, this review paper focuses on the experimental conditions employed for Cu–Ag electrodeposition, intending to understand the basis and manipulate the processes to obtain coatings with superior characteristics and for attractive usage. Finally, the most trending applications of these coatings are discussed depending on different parameters of electrodeposition to provide prospects for potential research. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to investigate the marginal adaptation of galvanoceramic inlay comparing two different ceramic inlays used in dental practice. Materials and methods: Class II inlay cavity was prepared on an ivorine mandibular left first molar and a metal master die was produced from stainless steel. Using electroforming machine, fifteen galvanoformed copings were produced firstly, and then galvanoceramic inlays were obtained by firing feldspathic porcelain on them. For comparison with ceramic inlays, two different groups were prepared from lithium disilicate and alumina ceramic. The absolute marginal discrepancy of galvanoformed copings and three different inlay restorations were measured onto the master die in described 16 different reference points by scanning electron microscope. Data obtained from the measurements were statistically analysed using paired t-test and two-way analyses of variance (α=.05). Results: The galvanoceramic inlays showed a significantly higher marginal discrepancy than other ceramic inlays (P<.001). The mean marginal discrepancy was 379±153µm for galvanoceramic inlays, whereas other inlays had marginal gaps under 200µm. Galvanoformed copings had lowest marginal gap, but the adaptation of these copings was failed after porcelain firing. Conclusion: Galvanoformed copings have superior marginal fit than other ceramic inlays, but the marginal gaps increased after porcelain firing and marginal adaptations became clinically unacceptable. Clinical usage of galvanoceramic inlays is questionable due to their marginal discrepancies. [ABSTRACT FROM AUTHOR]

Electrochromic (EC) mirrors fabricated using the electrodeposition of metals can dynamically transition between reflective and transparent states via the deposition and dissolution of the employed metals. In particular, the incorporation of an EC counter electrode enables the realization of an absorptive state under optimized applied voltage. Herein, we present reversible EC mirrors composed of Ag and WO 3 layers as the two electrodes, highlighting their EC properties in three optical transformation modes: transparent, reflective, and absorptive. The formation of Ag layers under optimized deposition conditions was confirmed, and the electrodeposited WO 3 layers exhibited compact or porous structures depending on the deposition conditions. The prepared Ag–WO 3 EC mirrors showed substantial transmittance modulation during the reflecting (53.7%) and coloring (63.5%) process. Interestingly, in comparison to the compact WO 3 , the EC mirrors with porous WO 3 layers exhibited dark-gray coloration in the reduced state, which was attributed to the localized surface plasmon resonance effect caused by codeposited Ag particles. [ABSTRACT FROM AUTHOR]

Rechargeable mild aqueous Zn/MnO2 batteries are currently attracting great interest thanks to their appealing performance/cost ratio. Their operating principle relies on two complementary reversible electrodeposition reactions at the anode and cathode. Transposing this operating principle to transparent conductive windows remains an unexplored facet of this battery chemistry, which is proposed here to address with the development of an innovative bifunctional smart window, combining electrochromic and charge storage properties. The proof‐of‐concept of such bifunctional Zn/MnO2 smart window is provided using a mild buffered aqueous electrolyte and different architectures. To maximize the device's performance, transparent nanostructured ITO cathodes are used to reversibly electrodeposit a high load of MnO2 (up to 555 mA h m−2 with a CE of 99.5% over 200 cycles, allowing to retrieve an energy density as high as 860 mA h m−2 when coupled with a zinc metal frame), while flat transparent FTO anodes are used to reversibly electrodeposit an homogenous coating of zinc metal (up to ≈280 mA h m−2 with a CE > 95% over 50 cycles). The implementation of these two reversible electrodeposition processes in a single smart window has been successfully achieved, leading for the first time to a dual‐tinting energy storage smart window with an optimized face‐to‐face architecture. [ABSTRACT FROM AUTHOR]

Molten salt electrodeposition is the process of producing impressively dense deposits of refractory metals using the electrolysis of molten salts. However, predicting which electrochemical parameters and setup will best control different kinds of deposition (density, homogeneity, etc.) is an ongoing challenge, due to our limited understanding of the properties and mechanisms that drive molten salt electrodeposition. Because these advancements have been made rapidly and in different arenas, it is worth taking the time to stop and assess the progress of the field as a whole. These advancements have increasing relevance for the energy sector, the development of space materials and engineering applications. In this review, we assess four critical facets of this field: (1) how the current understanding of process variables enhances the electrodeposition of various molten salts and the quality of the resulting product; (2) how the electrochemical setup and the process parameters (e.g., cell reactions) are known to impact the electrodeposition of different metal coatings and refractory-metal coatings; (3) the benefits and drawbacks of non-aqueous molten salt electrodeposition, and (4) promising future avenues of research. The aim of this work is to enhance our understanding of the many procedures and variables that have been developed to date. The expectation is that this review will act as a stimulant, motivating scientists to delve further into the investigation of refractory-metal alloys by utilizing molten salt electrodeposition. [ABSTRACT FROM AUTHOR]

The possibility of targeted electrodeposition of metal coatings in the lead–bismuth binary system is considered. The analysis of metal content in the deposits is performed using square-wave stripping voltammetry of solutions containing both lead and bismuth. The results are supported by the data of scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction analysis. The conditions for the formation of Pb7Bi3 (ε-phase), which is promising for the application in superconducting microelectronics, are found. [ABSTRACT FROM AUTHOR]

The demand for advanced camouflage technology is increasing in modern military warfare. Multispectral compatibility and adaptive capabilities are increasingly desired features in camouflage materials. However, due to the strong wavelength dependence and limited tunability of electromagnetic wave responses, achieving simultaneous multispectral compatibility and adaptive capability in a single structure or device remains a challenge. By integrating coding metamaterials with infrared (IR) electrochromic devices, we demonstrate a highly integrated multispectral metal-based electro-optical metadevice. The fabricated metadevices enable the reversible tunability of IR emissivity (0.58 at 3–5 µm, 0.50 at 7.5–13 µm) and wideband microwave scattering reduction (>10 dB at 10–20 GHz). The excellent integration performance is attributed to the remarkable electromagnetic control capabilities of the coding metamaterials in a chessboard-like configuration and the IR electrochromic devices based on metal reversible electrodeposition. Furthermore, the monolithic integrated design with shared barium fluoride substrate and electrodes allows the metadevices to have a simple architecture, and the careful design avoids coupling between functions. Our approach is general enough for the design of various electrochromic devices and metamaterials for multispectral camouflage, offering valuable insights for the development of advanced adaptive multispectral camouflage systems. [ABSTRACT FROM AUTHOR]

The arbitrarily formed golden cluster systems were created in the gas state which has strong Resistive Switching (RS) behavior around ambient temperatures and makes these attractive candidates for the creation of electronics geared toward neuron categorization along with information analysis. The cluster-assembled nanotechnology coatings that are fully linked have an irregular shape that includes neuromorphic crystallographic flaws, interactions and frontiers of grains, highlighting the complex interaction among electromagnetic in mechanical elements. In this analysis, we conduct a thorough investigation of the electroforming procedure that is utilized in the creation of film that was the cluster assembled. The present research sheds light regarding the electroforming procedure's substantial influence on the complex relations among nanopores and the mesoscale layer formations and underlying neurological properties of resistance switches activities that ensure. The findings provide insight into a methodical oversight of electroforming operation and reveal its function in building distinct patterns at various sizes in films of cluster assembled. The discovery not only improves our understanding of the intricate relationships among architectural and electrical parts but it provides opportunities for designing neurological structures that are randomly constructed and customized over multiple information-handling applications. [ABSTRACT FROM AUTHOR]

In the mass-production of microfluidic devices through micro hot embossing/injection moulding, the longevity of mould inserts is influenced by elevated adhesion and friction between the polymer and the mould. Thus, accurate prediction of mould lifespan requires a comprehensive understanding of surface wettability and tribological performance during polymer contact. The current study addresses this gap by characterizing fabricated micro-structured Ni, Ni-WS2, and Ni-PTFE nanocomposite moulds (surface morphologies, crystal structures and microhardness) to investigate inherent lubrication mechanisms. Surface wettability of mould material was systematically studied by measuring the contact angles with eight different polymer melts. Pin-on-disk tests with polymer pins made of cyclic olefin copolymer (COC 8007), polypropylene (PP), and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) were conducted to elucidate the wear resistance of the nanocomposite moulds. Pressure-dependent friction coefficient and wear resistance were further explored under increasing external loads, simulating the actual moulding processes where contact pressure may vary considerably depending on the part shape. Results indicate that Ni-WS2 exhibits the highest microhardness (532 Hv), followed by Ni-PTFE (465 Hv) and Ni (198 Hv). Notably, Ni-PTFE demonstrates exceptional hydrophobicity against all polymer melts, signifying low surface energy during polymer contact. Moreover, both nanocomposite moulds exhibit reduced friction coefficients and enhanced wear resistance across various polymers. Counterintuitively, despite its lower hardness, the Ni-PTFE mould displays superior wear resistance against the COC pin under higher loads, while the Ni-WS2 mould experiences severe adhesive wear, as observed from wear morphology and profile analysis. This finding establishes the Ni-PTFE as a promising alternative as a mould insert material for precision manufacturing.

Motivated by an interest in high-pressure research, thick (>1 mm) compositionally graded gold/silver (Au/Ag) films were electroformed. Systematic studies were performed to understand the role of processing temperature on the nucleation and growth kinetics and associated microstructure. Furthermore, as the electrolyte composition is continuously changing during the experiment, systematic studies were performed to correlate electrochemical parameters with film morphology and composition. The results showed that the nucleation pathways and relative deposition rate of Au and Ag are heavily dependent on the processing temperature. A procedure to ramp the temperature while continuously pumping an Au electrolyte into an initial Ag electrolyte to produce the graded film is presented. The obtained film is comprised of a segment of pure Au followed by a complete compositional gradient and ending with a segment of pure Ag across 1.5 mm. The results presented here describe a general framework to fabricate gradients of other materials through electrodeposition. [ABSTRACT FROM AUTHOR]

Localized electrochemical deposition microadditive manufacturing (AM) (LECD-µAM) technology represents a nontraditional manufacturing method applied for the layer-by-layer fabrication of metal microstructures via a fully automatic feedback mechanism. In terms of material utilization and complex structure formation, the proposed technology exhibits great potential for microstructure fabrication. The LECD-µAM technology introduced in this study involves the reduction of metal cations in the electrolyte to form metal microstructures. This study showed the flow simulation of an electrolyte in the cantilever probe and pressure distribution at the probe tip. In addition, the effect of extrusion pressure on the deposition structure was investigated experimentally. Combined with the experimental results, we discussed the effects of LECD-µAM technology on deposition outcomes and optimized parameters and designed a printing route for the deposition of complex metal microstructure arrays with smooth surfaces. The proposed technology attained a deposition rate and a microstructural copper content of 0.961 µm/s and 99.5%. In addition, LECD-µAM technology can be performed at room temperature, has low environmental requirements and cost, provides a good deposition surface, and holds great potential for the manufacture of three-dimensional and other complex microstructure arrays. Highlights: The technology realizes micron level complex structure additive manufacturing based on the hollow atomic force microscopy (AFM) cantilever probe. By designing the deposition path, adjust the extrusion pressure to control the deposition structure. The proposed technology attained a deposition rate and a microstructural copper content of 0.961 µm/s and 99.5%. It has the characteristics of faster speed and higher purity. [ABSTRACT FROM AUTHOR]