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The synthesis of abundant well-separated nanoparticles by electrodeposition is difficult since the electroplated nanoparticles tend to aggregate in their overlapping lateral diffusion zones. As a result, the facile electrodeposition method is rarely employed to prepare catalysts especially those for ammonia borane (AB) hydrolysis. Herein, well-separated amorphous CoFeNiP nanoparticles with a mean size less than 100 nm are obtained on Cu foams using galvanostatic electrodeposition. Remarkably, the glass-to-crystal structural transformation is activated in CoFeNiP after the first cycle of catalytic AB hydrolysis, accompanied by the changes in their morphology from monolithic nanoparticles to flower-like nano-ribbons with a characteristic size of ∼20 nm. The as-activated CoFeNiP alloy catalysts exhibit an enhancement in their performance of catalytic dehydrogenation of AB hydrolysis with a high turnover frequency of 12.5 min−1 at 303 K and a low apparent activation energy of 23.4 kJ mol−1, achieving ultrahigh durability after 5 cycles. The results demonstrate transition-metal phosphides could be used as practical noble-metal free alloy catalysts for hydrolytic dehydrogenation of AB with low cost, high performance and excellent recyclability. • Amorphous CoFeNiP (CFNP) alloy nanoparticles are successfully synthesized on Cu foam by electrodeposition. • The glass-to-crystal structural transformation is activated in the nanoparticles after the first cycle of catalytic ammonia borane (AB) hydrolysis. • The activated flower-like CFNP nano-ribbons with a characteristic size of ∼20 nm have enhanced TOF and durability. • Nano-flower CFNP alloys are ideal catalysts for hydrolytic dehydrogenation of AB with high performance. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the oxidation resistance and area specific resistance at high temperature of Ni/Co–W and Cu/Co–W electroplated type 445 stainless steels using co-electrodeposition. Coated samples were exposed to oxidation at a high temperatures 800 °C in air containing 3 vol.% water vapour for 96 h. X-ray diffraction analysis revealed that the oxidation process resulted in the formation of CoWO4 and Co3O4 on the Ni/Co–W sample, and CoWO4, Co3O4, CuWO4 and CoCr2O4 on the Cu/Co–W sample. The Ni/Co–W coated sample effectively suppressed the outward diffusion of chromium. The Cu/Co–W coated sample exhibited a higher oxidation rate than the Ni/Co–W coated sample. The oxidation kinetics of the coated samples obeyed the parabolic rate law. The Cu/Co–W coated sample exhibited a lower area specific resistance compared to the Ni/Co–W coated sample. [ABSTRACT FROM AUTHOR]

The performance of solid oxide electrolyzer cells (SOEC) can be improved through the development of coatings applied to the surface of ferritic steel interconnects in view of mitigating chromium evaporation and reducing the growth rate of low conductive oxides in oxidizing environments. This work investigated the oxidation and area specific resistance (ASR) of two electrodeposited nickel coatings on preoxidized and non-preoxidized AISI 441 ferritic stainless steel substrates. The nickel coating effectively restricted the outward diffusion of chromium after 100 h of exposure at 700 °C in air but led to nickel/iron interdiffusion between the substrate and coating forming an iron-nickel-rich spinel on the surface, with NiO underneath and Cr2O3 at the coating-substrate interface and at the coating grain boundaries. The application of a LSM ((La0.80Sr0.20)0.95MnO3−x) coating on top of the Ni electrodeposited coatings resulted in the same type of oxides but the oxidation kinetics were slower. Interdiffusion continued with the exposure at 700 °C for 2400 h resulting in the growth of a thick iron-rich oxide layer on top of Cr2O3, steadily raising the interconnect ASR to 25 mΩ cm2. The addition of a preoxidation step before the electrodeposit of nickel helped to limit iron-nickel interdiffusion, leading to the formation of a thicker NiO layer on a Cr2O3 layer between substrate and coating. While the ASR was higher than without preoxidation at the beginning of the test, it stabilized at about 33 mΩ cm2 after 1750 h. Despite displaying a higher electrical resistance, the coatings effectively limited the outward chromium diffusion throughout exposure compared to the bare substrate. [ABSTRACT FROM AUTHOR]

Stainless steel codeposition on a low-cost substrate is crucial because of economic factors. In this work, codeposition of FeCrNi thin film was successfully prepared galvanostatically from a novel environmentally friendly mixed complex (glycine-formate) bath on a steel surface. The novel bath is characterized by using environmentally benign Cr(III) rather than Cr(IV), at pH 7, applying low current density (id) at 25 °C, and finally producing crack-free nanostructured FeCrNi films with up to 18% Cr. The obtained FeCrNi thin film has a composition resembling that of stainless steel 304 (Ni 8% and Cr ~ 18%). The study was carried out using potentiodynamic polarization curves, chronoamperometric analysis, and anodic linear stripping voltammetry (ALSV), complemented by a scanning electron microscope and X-ray diffraction analysis. The atomic absorption test showed an acceptable range of Cr content (from 13.76 to 18.75 At. %) depending on the practical circumstances. The Cr% is enhanced slightly by decreasing the id and pH or raising the temperature. At deposition times of 20 and 60 min, the Cr content slightly decreased with increasing id. For example, the Cr content decreased from 17.88% (at 0.48 mA cm−2) to 13.98% (at 2.41 mA cm−2) and decreased from 17.14% (at 0.48 mA cm−2) to 13.94% (at 2.41 mA cm−2) respectively. The deposition of FeCrNi films has been characterized by instantaneous nucleation followed by 3D growth under charge transfer control. The phases were polycrystalline, and their grain size value was 8.93 nm. At a relatively high current density (2.41 mA cm−2), the coatings' surface morphology became uniform, extremely smooth, and nearly devoid of micro-cracks. However, a low bath pH of 4.0 results in observed multiple pits of varying sizes. [ABSTRACT FROM AUTHOR]

Fast technological progress in the electronics industry leads to an ever-growing generation of electronic waste or e-waste. Proper recycling of e-waste is, therefore, of great importance, not only for ecological reasons but also to valorize its material content. With gold being the most valuable metal in electronic waste, it is the main driver for recycling, even though it is only present in minor concentrations compared to base metals like copper and iron. This study presents a continuous flow module for potential-controlled electrowinning of gold out of AuCl4− complexes from a multi-metal solution containing nickel, copper, iron, and gold ions, as a representative solution of a typical Printed Circuit Board leachate after a pre-washing and gold leaching step. Concentrations as low as 0.1 mM of AuCl4− were selectively reduced to metallic gold on a glassy carbon plate in a continuous flow cell for 4 h with a maximum recovery of up to 86%. Both electrochemical and engineering parameters were investigated, such as the impact of the flow rate, potential, presence of competing reactions from other ions in the solution, and the addition of turbulence promoters in an attempt to optimize the electrowinning. An increase in recovery was observed by raising the flow rate, whereas the potential showed an optimum at + 0.4 V vs Ag/AgCl, with lower potentials leading to more side reactions and lower current efficiencies. Addition of turbulence promoters mainly played a role in the surface utilization and crystal growth, leading to similar overall recoveries but with a more homogeneous deposit and lower variation. With this technique, it is demonstrated that selective gold electrowinning from small concentrations in the presence of base metals, such as copper, nickel, or iron, is feasible in an efficient manner. [ABSTRACT FROM AUTHOR]

This work aims to electrodeposit Cr from a solution containing only Cr3+ ions but not any other complexing, buffering and pH agents, and study its corrosion behavior. The solution was investigated by cyclic voltammetry and ultraviolet–visible spectroscopy. It was obtained that it is rich in native Cr complexes including Cl. Cr was successfully coated from this solution by binary potential loop electrodeposition. First, − 0.7 V potential was applied for a time interval ranging from 5 to 30 s. Then, a − 1.8 V potential was applied to deposit the Cr layer with the thickness changed from 50 to 1000 nm. X-ray diffraction patterns showed that all films are in a bcc crystal structure. The Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy and optical profilometry measurements inferred that the coatings include hydrated-Cl complexes mostly edges of the coating and cracks. The scanning electron microscopy images indicated that the cracks on the surface are tiny for the layers thinner than 500 nm but prominent for the layers thicker than 500 nm. The corrosion behavior was examined by electrochemical impedance spectroscopy and Tafel measurements. The coatings electrodeposited by the binary potential loop had a corrosion rate lower and resistance higher than those of the coatings electrodeposited at − 1.8 V potential. The corrosion parameters became superior for the coatings with layers thinner than 500 nm and the aged ones. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction in alkaline water electrolysis is facilitated through the electrodeposition of trimetallic catalyst on nickel foam using the chronoamperometry technique. Specifically, the trimetallic catalyst CoWRu@NF is deposited onto a nickel foam substrate. The catalytic performance of this trimetallic catalytic electrode for the Hydrogen Evolution Reaction (HER) is then assessed in a 1.0 M potassium hydroxide (KOH) solution. This specially designed trimetallic catalytic electrode system efficiently provides the more active sites through the Co component. Subsequently, it facilitates the reduction of protons (H+) to generate hydrogen gas using the Ru component. Tungsten acts as a co‐catalyst in the system for water dissociation promotor by removing hydroxide formed after water dissociation and preventing the deactivation of Ruthenium by certain reaction intermediates. The CoWRu@NF trimetallic catalyst demonstrates excellent activity, showcasing a low overpotential (−8 mV) to achieve a current density of (−10 mA/cm2. Additionally, it exhibits low Tafel slope values (101.2 mV dec−1), credited to the presence of cobalt and tungsten alongside Ruthenium in the catalytic system. This configuration is specifically designed to enhance the kinetics of the hydrogen‐evolving reaction. [ABSTRACT FROM AUTHOR]

The study employs a multimicroscopy approach, combining Scanning Electrochemical Cell Microscopy (SECCM) and Field Emission Scanning Electron Microscopy (FESEM), to investigate electrochemical nucleation and growth (EN&G). Cu nanoparticles (NPs) are meticulously electrodeposited on glassy carbon (GC), to perform co‐located characterization, supported by analytical modeling and statistical analysis. The findings reveal clear correlations between electrochemical descriptors (i–t transients) and physical descriptors (NPs size and distribution), offering valuable insights into nucleation kinetics, influenced by varied overpotentials, surface state, and electrode's area. Analysis of the stochasticity of nucleation reveals intriguing temporal distributions, indicating an increased likelihood of nucleation with higher overpotential and larger electrode's area. Notably, the local surface state significantly influences nucleation site number and activity, leading to spatial differences in nucleation rates unaccounted for in macroscopic experiments. The updated analytical model for EN&G current transients, considering SECCM geometry, shows excellent agreement with FESEM measurements, facilitating the calculation of active sites within individual regions. These results deepen the understanding of EN&G phenomena from a new perspective, and lay the groundwork for further theoretical advancements, showcasing the great potential of current experimental methods in advancing precise electrochemical manufacturing of micro‐ and nanostructures. [ABSTRACT FROM AUTHOR]

This study focuses on the potentiostatic electrodeposition of copper indium and cadmium sulfide (CuS, In 2 S 3 , and CdS) thin films on copper substrates, aiming to develop efficient electrocatalysts for the electrochemical reduction of CO 2 and sustainable hydrogen generation. Utilizing Cu Kα radiation for X-ray diffraction (XRD) analysis, the crystal structures of the electrodeposited films were confirmed, revealing well-defined crystalline phases. The films exhibited average particle sizes of 55.99 nm for CuS, 50.37 nm for In 2 S 3 , and 63.51 nm for CdS. Cyclic voltammetry and chronoamperometry were employed to optimize the deposition parameters, ensuring efficient nucleation and growth of the metal sulfide films. The electrochemical performance of the synthesized electrocatalysts was rigorously tested, demonstrating their potential for CO 2 reduction under optimized conditions with the highest efficiency for CdS electrodes. Additionally, the electrodeposited CuS and CdS are of the p-type, and In 2 S 3 is of the n-type semiconductor were studied and verified by the Mott–Schottky test. CuS, In 2 S 3 , and CdS were found to have donor and acceptor concentrations (N D) of 1.68 × 106, 1.44 × 105, and 8.9 × 105 cm3, respectively. The photoelectrochemical measurements of the electrodeposited metal sulfides were studied at ambient temperature and under illumination, providing higher photocurrent responses for CdS and demonstrating its strong potential as a photoelectrode material for CO 2 reduction. This work underscores the significance of facile electrochemical synthesis methods in developing cost-effective and scalable electrocatalysts, paving the way for their integration into photoelectrochemical systems for green energy applications. [Display omitted] • Potentiostatic electrodeposition was used for CuS, In 2 S 3 , and CdS thin films. • XRD confirms high crystal phase purity and well-defined crystallinity. • Average particle sizes: CuS 55.99 nm, In 2 S 3 50.37 nm, CdS 63.51 nm. • CdS demonstrates the highest efficiency in electrocatalytic performance. • The study supports scalable, eco-friendly methods for CO 2 and H 2 applications. [ABSTRACT FROM AUTHOR]

This study investigates the development of Ni-Co/SiO 2 nanocomposite coatings on mild steel surface using pulsed-current electrodeposition method. The effects of incorporating SiO 2 nanoparticle and varying its concentration on the coatings' microstructure, microhardness, wear resistance, and frictional properties were assessed using field-emission electron microscopy, X-ray diffraction, Vickers microhardness testing, and dry sliding wear tests. The results indicated that the coatings exhibited two-phases of Ni-Co solid solution (α) with a face-centered cubic (FCC) crystal structure and hexagonal Co, a refined crystallite size of approximately 31 nm for Ni-Co and about 25 nm for Ni-Co/SiO 2 , along with a colony-like morphology that did not show any preferred growth direction. The amount of Ni-Co solid solution increased with the addition of SiO 2 nanoparticles. The composite coatings demonstrated enhanced microhardness of 581 HV, which is 52 % greater than that of the Ni-Co coating, as well as improved wear resistance and a reduced friction coefficient compared to the unreinforced alloy coating. However, higher SiO 2 content adversely impacted the tribological properties due to nanoparticle agglomeration. Analysis of the worn surfaces revealed a transition from abrasive wear to oxidative wear with increasing applied force for the coatings. [ABSTRACT FROM AUTHOR]

This study describes the properties of electroactive polypyrrole and its applications, with a focus on the roughness of the material. This parameter is crucial as it influences the applicability of coated layers, leading to highly adherent coatings or programmed wettability. The first raised aspect covers the electrodeposition procedure, which can help tailor the desired smoothness determined by roughness parameters. Features such as the deposition method, synthetic solution components, potential boundaries, substrate type, and utilized additives are evaluated. In the following section, the application aspects are discussed with a focus on modern, currently developed subjects such as medical applications, including cell-adherent coatings, antibacterial coatings, and drug delivery modules, as well as more technological fields like improved adhesion to the substrate and the improved mechanical properties of the deposited coating. [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]

Developing highly efficient and stable electrocatalysts in acidic media is essential for proton exchange membrane water electrolyzers (PEMWEs). Especially for oxygen evolution reaction (OER), high overpotential is needed to overcome the high thermodynamic energy barrier of water splitting. Herein, we report a high‐efficiency self‐supported ternary alloy OER catalyst with high activity and good durability in acidic electrolytes by a simple electrodeposition method. The as‐prepared electrocatalyst consists of Ru, Au, and Mn alloy which is deposited on the carbon fiber paper (denoted as RuAuMn‐CFP). The RuAuMn‐CFP exhibits superior activity and only requires an overpotential of 131 mV at 10 mA cm−2 and outstanding stability of 30 h (10 mA cm−2) in acidic media, which outperforms the commercial Ru/C and Ir/C catalysts. Besides, at an overpotential of 140 mV, the RuAuMn‐CFP catalyst exhibited a remarkable mass activity of 29.63 mA/mg for OER. It is 7.9 times and 23.8 times higher than the commercial Ru/C and Ir/C catalysts (3.73 mA/mg, 1.24 mA/mg, respectively). [ABSTRACT FROM AUTHOR]

Cu2O/TiO2 heterostructure is prepared by electrodepositing Cu2O on rutile phase TiO2 particles. The morphology, structural, and optical properties of Cu2O/TiO2 heterostructure are determined by scanning electron microscopy, Raman spectroscopy, X‐ray diffractometer, and UV–vis absorption spectrum. The Cu2O/TiO2 heterostructure photoelectrochemical‐type photodetector is constructed based on this heterostructure. Experimental results show that the photoresponsivity and visible light absorption of the Cu2O/TiO2 heterostructure are significantly enhanced compared to those of TiO2 and Cu2O which demonstrate that the Cu2O/TiO2 heterostructure with a special interfacial structure is conducive to accelerating the separation and transfer of photogenerated carriers. The photoresponsivity and photocurrent density of Cu2O/TiO2 can reach 154 μA W−1 and 15.6 μA cm−2 at 0 V. In addition, the photocurrent density of the Cu2O/TiO2 heterostructure steadily increases with the enhancement of irradiation power density. Moreover, no significant attenuation of the photocurrent density is observed in the prepared Cu2O/TiO2 heterostructure after 1800 s of photo‐on/off cycles. These results suggest that the Cu2O/TiO2 heterostructure‐based photodetector holds great potential in the photodetection field. [ABSTRACT FROM AUTHOR]

Superconducting hybrid structures based on single nanowires are a new type of nanoscale devices with peculiar transport characteristics. Control over the nanowire structure is essential for understanding hybrid electronic phenomena arising in such complex systems. In this work, we report a technique for the fabrication of cobalt nanowires by template-assisted electrodeposition using iR compensation, which allows revealing the fundamental dependence of the preferred direction of nanowire growth on the deposition potential. Long coarse-grained cobalt nanowires with a diameter of 70 nm have been implemented into Nb/Co/Nb hybrid structures. We demonstrate that using electrode fabrication techniques that do not contaminate the surface of the nanowire leads to a high quality of devices with low-resistance interfaces. Low-temperature resistivity of 4.94 ± 0.83 µ Ω cm and other transport characteristics of Co nanowires are reported. The absence of long-range superconducting proximity effect for Nb/Co/Nb systems with different nanowire length is discussed. [ABSTRACT FROM AUTHOR]

The glycerol oxidation reaction (GOR) for producing high‐value‐added organic compounds is of great research interest due to its potential in alleviating the energy crisis. Herein, a facile NH4Cl‐assisted electrodeposition strategy is reported to fabricate 3D nano‐forest array‐like hollow nanostructures. The hierarchical heterojunction by combining phosphorus doping Co(OH)2 nanosheets with Cu2S nanotube arrays (P‐Co(OH)2@Cu2S NTs/CF) is developed to realize the optimization on GOR. The optimized P‐Co(OH)2@Cu2S NTs/CF catalyst exhibits an exceptional activity with a formate Faradaic efficiency (FE) of 97.40% at a potential of 1.30 V (vs RHE). The experimental results indicate that this unique hollow nano‐forest structure, grown on a conductive support, can expose more active sites and facilitate electron transfer, thereby demonstrating excellent GOR performance. This work provides new opportunities for the design of electrocatalysts of high‐activity and low‐cost hollow heterostructure electrocatalysts for glycerol electrooxidation. [ABSTRACT FROM AUTHOR]

The unique coordination configuration of single‐atom materials (SAMs) allows precise reaction control at atomic‐level and a potential of unusual electrochemical reaction. Nevertheless, it is a big challenge to prepare main group element with high loading content. Here, multifield‐regulated synthesis (MRS) technology is utilized to rapidly produce single‐atom antimony (Sb) metal with a high loading of 15 wt.%. Ab initio molecular dynamics simulations reveal the significantly enhanced reaction kinetics of Sb and nitrogen‐doped graphene by multi‐physics field coupling. Compared with common metallic Sb nanoparticles, atomically dispersed Sb displays remarkably improved electrochemical reaction kinetics and stable structure due to the negligible variation of stresses and volume expansion during the pseudocapacitive alloying‐dealloying process. Such extraordinary alloying reaction in well‐dispersed Sb atoms enabling homogeneous ion flow can serve as active nucleation sites for regulating even Na metal nucleation and growth. As a result, copper foil coated with only ≈3 µm thickness of such material exhibits a high Coulombic efficiency of up to 99.99%, an ultra‐low overpotential of 3 mV, and a long lifetime exceeding 2500 h in symmetrical cells. Furthermore, an anode‐free MRS‐SbSA||Na3V2(PO4)3 battery is constructed, which demonstrates exceptionally high energy density (≈362 Wh Kg−1), outstanding rate capability and good cycling stability. [ABSTRACT FROM AUTHOR]

Transition metal‐based electrocatalysts play a crucial role in the oxygen evolution reaction (OER). However, their heavy reliance on free electrons at the d‐band significantly limits the screening of potentially efficient, earth‐abundant alternatives. Despite extensive exploration of catalyst engineering through multi‐metal cooperation to modulate electron configuration by introducing additional transition metals, practical success remains elusive. Here, we present a straightforward electrodeposition method for preparing amorphous FeCoAl hydroxide catalysts. The introduction of Al contributes external free electrons, enabling a well‐defined electron configuration for intermediate adsorption. Al doping also adjusts the d‐band position of adjacent Co atoms, bringing them closer to the Fermi level and significantly enhancing intrinsic activity at the active sites. Furthermore, Al dopants facilitate rapid mass and charge transfer near the catalyst layer, promoting faster reaction kinetics. Leveraging these properties, the FeCoAl hydroxide catalyst achieves a large current density of 100 mA cm−2 at an overpotential of 340 mV, with a small Tafel slope of 29.1 mV dec−1. Our work provides valuable insights for designing efficient electrocatalysts by leveraging free electron‐rich metal doping and expanding the parameter space for catalyst engineering. [ABSTRACT FROM AUTHOR]

Hydrogen is a renewable and environmentally friendly energy carrier and is considered a viable alternative to fossil fuels. Consequently, developing electrodes with excellent hydrogen evolution electrocatalysis is a top priority in research. However, the use of flat electrodes as cathode substrates by most researchers limits the electrocatalytic active area of the prepared electrode. To address this issue, it is essential to prepare a micro-nano structure on a cathode substrate before electrodeposition. This study introduced a novel Ni nanocone/Grid electrode, obtained through a combined laser-electrodeposition process to investigate its electrocatalytic activity and stability for the hydrogen evolution reaction (HER). Various techniques, including linear sweep voltammetry (LSV), electrochemical impedance spectra (EIS), cyclic voltammetry (CV), and chronopotentiometry (CP) in 1 M KOH solution, were employed to assess the HER electrocatalytic performance of the Ni nanocone/Grid electrodes. The experimental results demonstrated that the electrodes could achieve current densities of -10, -20, and -100 mA/cm2 with corresponding overpotentials of -281, -308, and -390 mV, respectively. Additionally, the Tafel slope of these electrodes was found to be only -82.05 mV/dec. The enhanced catalytic performance of the electrode was attributed to the synergistic effect of the grid-like and nanocone structures, which significantly increased the electrocatalytically active area and improved surface hydrophilicity, thereby boosting electrocatalytic performance. The simplicity of the preparation method and the exceptional performance of the electrode provide a promising new avenue for future research on HER electrocatalysts. • A new laser-electrodeposition combined process was proposed to prepare the catalytic electrode for hydrogen evolution. • Ni nanocone/Grid showed low overpotential and Tafel slope for hydrogen evolution. • The combination of grid structure and nanocone can significantly increase the ECSA of the electrode. • The electrode shows excellent hydrophilicity and extraordinary durability. [ABSTRACT FROM AUTHOR]

The development of an efficient yet cost-effective non-precious electrocatalyst for the hydrogen evolution reaction (HER) in alkaline water and seawater systems remains a formidable obstacle to the large-scale production of hydrogen energy, stemming from the sluggish kinetics of electron transfer reactions during the HER process. In this article, an amorphous Co-P-W electrocatalyst on nickel foam is prepared using a brief cyclic voltammetry (CV) electrodeposition method. The optimized Co-P-W electrocatalyst exhibits excellent electrocatalytic performance for HER, which only requires overpotentials of 59 and 143 mV to achieve a current density of 10 mA cm−2 in alkaline water (1.0 M KOH) and alkaline seawater (1.0 M KOH + natural seawater), respectively, and remarkable stability and durability. The improved HER performance of the Co-P-W electrocatalyst is attributed to the introduction of W, which modulates the electronic structure of Co and P, optimizes the adsorption/dissociation of H 2 O, and reduces the charge transfer resistance of the Co-P electrocatalyst, thus improving the kinetics of the HER. Furthermore, the W-doping significantly enhances the hydrophilicity of the Co-P electrocatalyst, which favors rapid and thorough penetration of electrolytes into the electrocatalyst, facilitating the formation of a highly accessible reaction interface, ultimately resulting in excellent HER activity. Our findings demonstrate the feasibility of designing an efficient, durable, and scalable electrocatalyst to significantly boost HER efficiency for practical water electrolysis. [Display omitted] • Binder-free Co-P-W catalyst for electrocatalytic hydrogen production was developed via electrodeposition method. • The low η 10 in alkaline water and seawater were 59 and 143 mV, respectively. • Mo adjusts the electronic structure to optimize the adsorption/dissociation of H 2 O. • W doping increases the active area, enhances the conductivity and hydrophilicity, and greatly improves its intrinsic activity. [ABSTRACT FROM AUTHOR]

Metal foams are promising materials for the flow fields of proton exchange membrane fuel cells (PEMFCs) because of excellent mass transport characteristics and high electronic conductivity. To resolve the corrosion problem in the acidic environment under high temperature, nickel/graphene (Ni/G) composite coatings with hierarchical structures were electrodeposited on the surface of Ni foam. The effect of grain size and the distribution in the double layer was discussed. It was found that Ni/G5-10, with larger inner size and middle outer size, exhibited the best corrosion performance. Meanwhile, the corrosion current in the Tafel plots and the steady current density in constant potential analysis was lower than that obtained under steady and gradient currents. Combined with the results of XRD, XPS, and SEM, it was proven that a uniform and dense protective film was produced during the two-step electrodeposition. Moreover, the ICR value was 8.820 mΩ·cm2, which met the requirement of 2025 DOE. [ABSTRACT FROM AUTHOR]

This review provides a detailed analysis of the current transition observed in the field of electrodeposition of metals. Special emphasis is placed on the mechanism initiated by nucleation followed by diffusion‐controlled growth. The study highlights recent advances, relevant theoretical models, and practical implications of this process. Concrete examples are also discussed to illustrate the application of this method in various industrial and scientific contexts. These promising advances open new perspectives for the optimization of electrodeposition processes, paving the way for innovative applications in various technological sectors. [ABSTRACT FROM AUTHOR]

In this study, in situ electrodeposition of Zn─Al‐layered double hydroxides (Zn─Al‐LDHs) on the surface of pencil graphite substrate were practiced with interlayer modification by ibuprofen. The prepared composite increases the efficiency of the proposed method by increasing the level of interaction between the sorbent and the selected analytes including acetylsalicylic acid and naproxen (NAP) in real sample. Eventually, the extracted target analytes were injected into high‐performance liquid chromatography ultraviolet (HPLC‐UV) for their measurement. The experimental design including PBD and BBD was implemented to obtain the maximize efficiency and optimal condition for extraction of the target analytes. Therefore, in optimal conditions, limits of detection of 0.33–0.64 µg L−1, linear dynamic range (LDR) of 1–100 µg L−1 (with r2 > 0.9934), and limits of quantification (LOQs) of 1.1–2.1 µg L−1 were obtained for target analytes by SPME‐HPLC‐UV. The intra‐day relative standard deviation (RSD%) were found to range in 3.90%–5.30% (4.90%–6.80%) at concentration of 5–50 µg L−1 (2–10 µg L−1). According to obtained result, the relative recovery was calculated between 90% and 109%. Therefore, the obtained results showed that the selected method has a suitable performance for the preconcentration and extraction of acetylsalicylic acid and NAP in biological samples. [ABSTRACT FROM AUTHOR]

The climate crisis has become the most serious concern of human beings and environments worldwide in the 21st century. Global concerns about cancer epidemiology mainly originate from anthropogenic activities, particularly fossil-based operations. A key solution to this problem is the use of fuel cells—devices—capable of the direct conversion of fuel chemical energies like urea into electricity. To make their commercialization reasonable, one of the problems that needs to be solved is the development of anodic materials. The majority of investigations on urea oxidation are based on nickel, but its inadequate activity limits the efficiency of these devices. In this work, we propose and synthesize a Ni-Cu-Fe ternary electrocatalyst for urea oxidation through a fast and facile electrodeposition method. The properties of the synthesized material are examined by Scanning Electron Microscopy (SEM) conjugated with Energy Dispersive X-ray Spectroscopy (EDS), Transmission Electron Microscopy (TEM), and X-ray Diffraction (XRD). Its electrochemical properties were also examined in a 1 M KOH solution with and without 0.15 M urea. We found that the prepared powder is active in the electro-oxidation of urea, with 1.65 Vvs RHE required for a current density of 10 mA cm−2 and a stable potential of 2.38 Vvs RHE required for 3 h of polarization at 10 mA cm−2. [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 order to improve the activity of copper (Cu) towards electrolytic reduction of nitrate, thin films of magnesium hydroxide (Mg(OH)2) were deposited on Cu substrate. For the first time, these films were synthesized by electrochemical deposition in a potassium sulfate bath containing Mg2+ at 70 °C. The effect of various experimental parameters, such as deposition time and potential, on the electrocatalytic activity for the nitrate reduction was investigated. Surface analysis techniques (SEM, EDX and XRD) were used to get information on the morphology, the composition and the structure of the deposits. The activity of the modified electrode was studied by cyclic voltammetry, and amperometric method. The modified Mg(OH)2/Cu sensor exhibited a good electrocatalytic behavior towards the reduction of nitrates with high reproducible reduction peak currents. In addition, the sensor exhibits a linear answer for concentration in nitrate between 0.125 to 7 mM, combined with high sensitivity (24.6 µA mM−1 cm−2) and limit of detection (225.35 µM) values. When common interfering molecules were added to the solution, Mg(OH)2/Cu electrodes have kept their good selectivity. They demonstrated acceptable detection levels for nitrates in tap water. [ABSTRACT FROM AUTHOR]

This work reports the electrochemical fabrication of thin films comprising polyaniline nanofibers (PANI) in conjunction with graphene oxide (GO) and reduced graphene oxide (rGO) on ITO substrate, along with examining the electrochemical properties, with a focus on the influence of the substrate and electrolyte in the electrodeposition methods. The study explores the electrochemical characteristics of these thin films and establishes a flexible framework for their application in diverse sectors such as sensors, supercapacitors, and electronic devices. It analyzes the impact of the substrate and electrolyte in electrodeposition techniques. The effects were studied using techniques such as cyclic voltammetry and chronoamperometry. The fabrication process of PANI/GO and PANI/rGO thin films involved the integration of rGO within PANI via electropolymerization, conducted under sulfuric acid. GO was synthesized by modifying the well-known Hummers' method and characterized by X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). SEM showed the diameters of the formed PANI were between 40 and 150 nm, which helped to intertwine the rGO nanosheets with PANI nanofibers to form thin films. The electrochemical behavior of the PANI/rGO thin films was examined using cyclic voltammetry (CV) and chronoamperometry in different electrolytes, including sulfuric acid (H₂SO₄) and potassium nitrate (KNO₃). The CV profiles exhibited distinct oxidation and reduction peaks, with variations in the voltammogram morphology attributed to the nature of the electrolyte and the substrate employed during the electrodeposition process. These results highlight the critical role of both the substrate and electrolyte in governing the electrochemical performance of PANI/rGO thin films. The findings from this study demonstrate a versatile approach for the fabrication of PANI/graphene-based thin films with tunable electrochemical properties, and such a strategy has great application to fabricating other thin film composites for supercapacitors or other control source frameworks requiring enhanced charge storage and electrochemical responsiveness. [ABSTRACT FROM AUTHOR]

As a model of passivation at a micro or nanoparticle, we have modelled a passivating reaction at a microelectrode of hemispherical geometry. The reaction is considered to lead to either the formation of a surface-bound species or diffusion of product into bulk solution. A dimensionless parameter, p, of value 0 to 1.0 can be used to describe the balance between the two processes. We have simulated the first two linear sweep voltammograms (LSV) under different values of p and have simulated the peak width of the first LSV under different values of scan rate and p. These simulations were used to relate the peak width to the value of p. The results were compared to the characteristics of passivation at a microdisk electrode. The equation was used to analyse the oxidation of dopamine at hemispherical Ga electrodes, fabricated by the deposition of liquid phase Ga onto Pt microdisks. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) with redox-active metal ions and a variety of organic linkers have been widely investigated as prospective electrode materials for supercapacitors. Here, we generate uniformly dense spherical particles on a nickel foam substrate by a simple and binder-free one-step electrodeposition method by adjusting the deposition conditions. The active cobalt in the Co-MOF thin films can provide a large number of redox sites for the electrochemical reaction, while the uniform binder-free Co-MOF structure can keep enough contact area with the electrolyte to reduce the ion transport resistance. As-prepared CTB-0.9 (Co-MOF with a deposition voltage of − 0.9 V) thin film has a specific capacitance of 797.5 F g−1 at a current density of 1 A g−1, exhibiting excellent electrochemical properties. An asymmetric supercapacitor with CTB-0.9 as the positive material and activated carbon as the negative material also demonstrates competitive electrochemical performances, which has a high energy density of 34.3 Wh Kg−1 at a power density of 36,317.6 W Kg−1. This work may open up an effective approach to realize the electrosynthesis of Co-MOF films, promoting the utilization of Co-based MOFs in energy storage and conversion fields. [ABSTRACT FROM AUTHOR]

The demand for energy surpasses the available supply, leading to various economic, social, and environmental consequences. Hydrogen is one of the most clean and renewable source for energy. Therefore, the electrocatalytic hydrogen evolution reaction (HER) presents a promising eco-friendly approach for generating sustainable hydrogen energy. However, in alkaline conditions, HER encounters slow kinetics due to challenges associated with hydrogen adsorption and hydrolysis. In this article, thin Ni films were synthesized using the electrodeposition technique from citrate electrolyte. Their suitability as electrocatalysts for the hydrogen evolution reaction (HER) in a 1 M NaOH solution was estimated. This research investigates how the uniform magnetic field and temperature affect the process of nickel electrodeposition from a citrate bath and its subsequent influence on surface morphology and catalytic properties for the hydrogen evolution reaction (HER). Additionally, alterations in surface material wettability were examined based on changing the temperature during using the magnetic field for the electrodeposition process and shows how this effect on the catalytic performance towards HER. The outputs show that using the magnetic field for fabrication of Ni thin films at room temperature enhances the surface morphology and its catalytic performance for HER. However, the study reveals that using the temperature for Ni electrodeposition improves its catalytic performance independently of the magnetic field, whereas combining temperature with the magnetic field for Ni thin film fabrication diminishes their catalytic performance for the hydrogen evolution reaction (HER). The nickel thin film produced at 25 °C under the influence of a magnetic field, whether parallel or perpendicular, demonstrates the lowest overpotential of − 268 mV to achieve a current density of 10 mA cm−2. Additionally, it exhibits the smallest Tafel slope values of 106 mV dec−1 and 128 mV dec−1 for the parallel (Bǁ) and perpendicular (BꞱ) directions, respectively. However, the magnetic field effect diminishes at elevated temperatures. Nickel thin films prepared at 35 °C under the influence of perpendicular (BꞱ) and parallel (Bǁ) directions exhibit higher overpotential values of − 314 mV and − 322 mV, respectively. [ABSTRACT FROM AUTHOR]

Herein, a heterogeneous structure of Ni–Mo catalyst comprising Ni4Mo nanoalloys decorated on a MoOx matrix via electrodeposition is introduced. This catalyst exhibits remarkable hydrogen evolution reaction (HER) activity across a range of pH conditions. The heterogeneous Ni–Mo catalyst showed low overpotentials only of 24 and 86, 21 and 60, and 37 and 168 mV to produce a current density of 10 and 100 mA cm−2 (η10 and η100) in alkaline, acidic, and neutral media, respectively, which represents one of the most active catalysts for the HER. The enhanced activity is attributed to the hydrogen spillover effect, where hydrogen atoms migrate between the Ni4Mo alloys and the MoOx matrix, forming hydrogen molybdenum bronze as additional active sites. Additionally, the Ni4Mo facilitated the water dissociation process, which helps the Volmer step in the alkaline/neutral HER. Through electrochemical analysis, in situ Raman spectroscopy, and density functional theory calculations, the fast HER mechanism is elucidated. [ABSTRACT FROM AUTHOR]

The main challenges faced by aqueous rechargeable nickel‐zinc batteries are their comparatively low energy density and poor cycling stability, mainly due to the limited capacity and reversibility of existing Ni‐based cathodes. Moreover, the preparation procedures of these cathodes are complex and not easily scalable, which makes them less promising for large‐scale energy storage. Herein, we utilized MXene as a functional additive to effectively improve the electrodeposition preparation of NiCo layered double hydroxides (LDH). Benefiting from the improved interfacial contact between nickel foam (NF) and platting solution and the enhanced ionic conductivity of platting product based on MXene additives, the resulting binder‐free NiCo LDH electrode can achieve ultrahigh areal loading (~65 mg cm−2) with abundant active surface for redox reactions and maintained short transport pathway for ion diffusion and charge transfer. Furthermore, the as‐fabricated alkaline NiCo LDH‐based battery delivers high discharge capacity, up to 20.2 mAh cm−2 (311 mAh g−1), accompanied by remarkable rate performance (9.6 mAh cm−2 or 148 mAh g−1 at 120 mA cm−2). Due to the high structural and chemical stability of MXenes/LDH‐based electrode, excellent cycling life can also be achieved with 88.6 % capacity retention after 10000 cycles. In addition, ultrahigh areal energy density (31.2 mWh cm−2) and gravimetric energy density (465 Wh kg−1) can be simultaneously achieved. This work has inspired the design of advanced cathode materials to develop high‐performance aqueous zinc batteries. [ABSTRACT FROM AUTHOR]

The main challenges faced by aqueous rechargeable nickel‐zinc batteries are their comparatively low energy density and poor cycling stability, mainly due to the limited capacity and reversibility of existing Ni‐based cathodes. Moreover, the preparation procedures of these cathodes are complex and not easily scalable, which makes them less promising for large‐scale energy storage. Herein, we utilized MXene as a functional additive to effectively improve the electrodeposition preparation of NiCo layered double hydroxides (LDH). Benefiting from the improved interfacial contact between nickel foam (NF) and platting solution and the enhanced ionic conductivity of platting product based on MXene additives, the resulting binder‐free NiCo LDH electrode can achieve ultrahigh areal loading (~65 mg cm−2) with abundant active surface for redox reactions and maintained short transport pathway for ion diffusion and charge transfer. Furthermore, the as‐fabricated alkaline NiCo LDH‐based battery delivers high discharge capacity, up to 20.2 mAh cm−2 (311 mAh g−1), accompanied by remarkable rate performance (9.6 mAh cm−2 or 148 mAh g−1 at 120 mA cm−2). Due to the high structural and chemical stability of MXenes/LDH‐based electrode, excellent cycling life can also be achieved with 88.6 % capacity retention after 10000 cycles. In addition, ultrahigh areal energy density (31.2 mWh cm−2) and gravimetric energy density (465 Wh kg−1) can be simultaneously achieved. This work has inspired the design of advanced cathode materials to develop high‐performance aqueous zinc batteries. [ABSTRACT FROM AUTHOR]

This work reports the effects of potassium bromide (KBr) on the electrodeposition of manganese on copper from a DES consisting of a stoichiometric 1:2 mix of choline chloride and ethylene glycol (Ethaline 200). The speciation of MnCl2.4H2O in Ethaline 200 has been investigated using UV–vis spectroscopy, in particular with regard to the addition of KBr to the plating bath, for which no apparent change in the Mn species was noted. This said, the physical properties of the manganese deposits themselves were found to have been considerably improved in comparison to when KBr was omitted from the bath; indeed, the actual adhesion of Mn was achieved for the first time on a copper substrate, somewhat remarkably producing a coating of some considerable thickness. Given its clear electrochemical behavior of the Mn liquid were subsequently determined via cyclic voltammetry method. A reduction in the peak current of Mn was noted on addition of KBr. The mechanism of Mn deposition has been examined via chronocoulometry and chronoamperometry. Surface analyses of Mn deposits have been conducted via SEM/EDX, AFM, and XRD, from which improvements to the Mn surface coatings in depositions performed from an electrolyte containing 0.1 M KBr were noted. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) presents a major challenge for water splitting due to its slow kinetics. In this study, Co-Fe-Gr nanocomposite coatings were developed on carbon steel via electrodeposition using graphene (Gr) at concentrations of 0.02, 0.04, and 0.06 g/L to enhance OER performance. The sample with 0.02 g/L Gr exhibited a unique cauliflower-like morphology with aligned cobalt, as revealed by FE-SEM, leading to an increased electrochemical surface area. This optimal nanocomposite (Co-Fe-Gr (0.02 g/L)) demonstrated a low overpotential of 88 mV at 10 mA cm2, high stability (4.2 mF cm⁻2), and low resistance (R = 7.5 Ω cm⁻2). Additionally, it showed a small Tafel slope of 6.6 mV/dec and maintained stability after 12 h. A turnover frequency (TOF) of 73.6 s⁻1 indicated that graphene doping significantly reduced the adsorption energy of intermediates, greatly enhancing OER activity for efficient water splitting applications. [Display omitted] • Co-Fe-Gr nano-composite electrocatalysts were fabricated using an electrodeposition process. • Increasing the Gr content increased the Gr sheets and reduced the number of active sites. • The Co-Fe-Gr (0.02 g/L) with cauliflower-like morphology had an electrochemically active surface. • The Co-Fe-Gr (0.02 g/L) nano-composite showed the highest electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Energy generation today heavily relies on the field of photocatalysis, with many conventional energy generation strategies now superseded by the conversion of solar energy into chemical or thermal energy for a variety of energy-related applications. Global warming has pointed to the urgent necessity of moving away from non-renewable energy sources, with a resulting emphasis on creating the best photocatalysts for effective solar conversion by investigating a variety of material systems and material combinations. The present study explores the influence of morphological changes on the photoelectrochemical activity of zinc oxide nanostructures by exploiting electrodeposition and capping agents to control the growth rates of different ZnO facets and obtain well-defined nanostructures and orientations. A zinc nitrate (Zn (NO3)2) bath was used to electrodeposit ZnO nanostructures on an indium tin oxide glass (ITO) substrate at 70 °C with an applied potential of −1.0 V. Ethylenediamine (EDA) or ammonium fluoride (NH4F) were added as capping agents to the zinc nitrate bath. Extensive evaluation and characterization of the photoelectrochemical (PEC) capabilities of the resulting morphology-controlled zinc oxide nanostructures confirmed that altering the ZnO morphology can have positive impacts on PEC properties. [ABSTRACT FROM AUTHOR]

Transition metal ions and their complexes play a crucial role in homogeneous catalysis. These catalysts are pivotal for the production of, for example, fine chemicals and pharmaceuticals. Nevertheless, because of the homogeneous nature of these catalysts, their extraction and removal from the crude reaction mixture is cumbersome. Here, we propose an alternative approach where metal‐based homogeneous catalysts are generated electrochemically from a metallic anode (Cu), followed by their use without current, and finally again electrochemically deposited on the cathode. The generated Cu ions were used as catalysts in three different reactions of lauroyl peroxide: one ligand‐free (coupling with dienes), one without ligand but with a heteroatom containing substrate (coupling with toluidine and styrene) and one in the presence of 1,10‐phen as ligand (coupling with indazole). In the first two cases, performance of the electrochemically generated catalysts was similar to those reported in literature for classically prepared homogeneous catalysts, whereas in the last case a new reaction was observed. After reaction, the homogeneous copper catalyst could be efficiently removed electrochemically: 99% of the copper could be removed for the ligand‐free reaction, 97% for the amine coupling, whereas 89% of copper could be removed for the reaction containing N‐heterocycle and 1,10‐phenanthroline. [ABSTRACT FROM AUTHOR]

This study reports a unique flow-through electrode design for hydrogen production in alkaline water electrolysis. This paper investigates a variety of electrodeposition coatings on the 3D-printed electrodes, including nickel, nickel-copper, and nickel-iron. The catalytic activity and properties of the electrodes are examined through electrochemical measurements involving linear sweep voltammetry, cyclic voltammetry, electrochemical impedance spectroscopy, and surface morphology analysis. An experimental setup is also developed to measure hydrogen production and evaluate the efficiency of the designed electrodes. The study finds the flow-through electrodes coated with nickel-copper and nickel-iron achieve the current densities of 54 mA/cm2 and 45 mA/cm2, respectively. The activation overpotentials for the nickel-copper coated electrode are reported as 539 mV, and 408 mV for the nickel-iron coated electrode, both at a current density of 10 mA/cm2. The highest production rate is obtained within the first 15 minutes, 0.273 μg/s for the Ni-Cu flow-through electrode and 0.255 μg/s for the Ni-Fe flow-through electrode. The study further shows that flow-through electrodes produce hydrogen with an efficiency approximately 74% higher than traditional electrodes, suggesting a potentially better design for better hydrogen production in industrial applications. • This study reports a new flow-through electrode design for hydrogen production. • The electrodes are fabricated using 3D-printing and coated using electrodeposition. • The performance is evaluated using electrochemical and hydrogen measurements. • The study finds that flow-through electrodes perform better than traditional. • The flow-through electrodes consume less energy with the same or higher production. [ABSTRACT FROM AUTHOR]

In this work higher Cu2+ removal efficiency was achieved by graphene oxide GO-based electrode with the constant magnetic field (CMF)-assisted electrodeposition system. The GO was initially synthesized by the electrochemical exfoliation method in the electrolyte containing custom-made surfactant. The as-prepared GO solution was then spray coated on the pre-heated stainless steel-cathode before annealed at 400°C for 1 hour. GO-based electrode with CMF-assisted electrodeposition system was successful removed 89.1% of Cu2+ from aqueous solutions as compared to the electrode without GO of only 75.5% of Cu2+ removal within a fixed 3 hours' time. The efficient of Cu2+ removal by GO-based electrode was believed due to the high specific surface area of GO that increases the accommodation of the active species (Cu2+) at the electrode surfaces. In the meantime, it was found that the presence of CMF of 23 Gauss parallel to cathode surfaces enhances the convection and mass transport of Cu2+ charged species to the electrode as compared to the absence of the CMF on an electrodeposition system. This phenomenon was due to the Magneto-Hydrodynamics (MHD) effect of CMF which is based on the Lorentz force that increases the Cu2+ deposition efficiency by reducing the diffusion layer thus increasing the ions transfer into the electrical double layer. The electrodes before and after Cu2+ deposition was examined by electron microscopy, energy dispersive x-ray, and Raman spectroscopy, and the concentration of remaining Cu2+ in the solution was analyzed using atomic absorption spectroscopy. From the analysis done shows that the GO-based electrode with CMF-assisted electrodeposition system pave a new and pragmatic route for efficient removal of heavy metal ions. [ABSTRACT FROM AUTHOR]

Cobalt-vanadium layered bimetallic hydroxide (CoV-LDH) is rich in electrochemically active sites, but still suffers from the problems of expensive low-priced vanadium sources, difficult preparation, and vanadium dissolution. In this study, three-dimensional porous CoV-LDH electrode materials were prepared by electrochemical cathodic reduction, and in order to improve the stability of CoV-LDH in alkaline electrolyte, the core-shell structure CoV-LDH@NiCo-LDH composites were constructed by secondary electrodeposition, which have the microscopic morphology of nanosphere-coated nanosheets and the uniform distribution of the three elements of Ni, Co, and V. This increased the contact area of the material's active sites and the electrolyte, and reduced the contact area of vanadium. With the uniform distribution of Ni, Co and V elements, the contact area between the active sites and the electrolyte is increased, the interfacial impedance of the material is reduced, and the pseudocapacitive energy storage performance is greatly improved. Under the current density of 1 A/g, the specific capacitance of CoV-LDH@NiCo-LDH reaches 995.8 F/g, which is much better than that of CoV-LDH (575.2 F/g), with a significant increase of 73.1% in the specific capacitance, and it has excellent multiplicative performance, and the pseudocapacitance accounts for 85% of the total capacitance under the sweeping speed of 50 mV/s. The cycling stability reaches 85% after 2 000 cycles. Analyzing the reaction kinetics and energy storage mechanism of the NiCo-LDH@CoV-LDH electrode material, it exhibits not only the battery-type Faraday behavior but also the capacitive properties. The anode material was assembled with an activated carbon (AC) negative electrode to form a CoV-LDH@NiCo-LDH:||AC asymmetric supercapacitor, with a specific capacitance of up to 222.2 F/g at a current density of 1 A/g, and an energy density of 30.86 Wh/kg at a power density of 222.2 W/kg. This work lays the foundation for the vanadium-based bimetallic hydroxide material, preparation of vanadium-based bimetallic hydroxide materials and energy storage applications. [ABSTRACT FROM AUTHOR]

Copper oxide, Cu2O is a highly versatile product that can obtained by different techniques including high/low temperature thermal oxidation, sputtering, chemical oxidation, anodic oxidation, electrodeposition, among others. Until now, the most efficient synthetic processes to obtain Cu2O require relatively expensive equipment; therefore, we have developed a novel method based on simultaneous convergent oxidation-reduction reactions in an electrolytic cell at ambient pressure and relatively low temperature. In this work, a Cu(0) plate is oxidized to Cu(I) in the anodic compartment, while a Cu(II)- lactate complex is formed in the cathodic compartment of the cell and then Cu(II) is reduced to Cu(I), all in aqueous media. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate the electrodeposition of copper nanoparticles (NPs) on pencil graphite electrodes (PGEs) utilizing sodium dodecyl sulphate (SDS) as a soft template. The utilization of the surfactant had an impact on both the physical arrangement and electrochemical characteristics of the modified electrodes. The prepared Cu-SDS/PGE electrodes had hierarchical dendritic structures of copper NPs, thereby increasing the surface area and electrochemical catalytic activity in comparison with Cu/PGE electrodes. The Cu-SDS/PGE electrode showed excellent catalytic activity in reducing hydrogen peroxide, resulting in the sensitive and selective detection of hydrogen peroxide. The electrode exhibited a good sensitivity of 21.42 µA/µM/cm2, a lower limit of detection 0.35, and a response time of less than 2 s over a wide range spanning 1 µM to 1 mM of hydrogen peroxide concentrations. The electrodes were also highly selective for H2O2 with minimal interference from other analytes even at concentrations higher than that of H2O2. The approach offers the benefit of electrode preparation in just 5 min, followed by analysis in 10 min, and enables for the quantitative determination of hydrogen peroxide within 30 min. This can be achieved utilizing a newly prepared, cost-effective electrode without the need for complex procedures. [ABSTRACT FROM AUTHOR]

Photoelectrochemically active WO3 films were fabricated by electrodeposition from an acidic (pH 2), hydrogen-peroxide-containing electrolyte at −0.5 V vs. SCE. WO3-TiO2 composites were then synthesized under the same conditions, but with 0.2 g/L of anatase TiO2 nanoparticles (⌀ 36 nm), mechanically suspended in the solution by stirring. After synthesis, the films were annealed at 400 °C. Structural characterization by XRD showed that the WO3 films exhibit the crystalline structure of a non-stoichiometric hydrate, whereas, in WO3-TiO2, the WO3 phase was monoclinic. The oxidation of tungsten, as revealed by XPS, was W6+ for both materials. Ti was found to exist mainly as Ti4+ in the composite, with a weak Ti3+ signal. The efficiency of the WO3 films and composites as an oxygen evolution reaction (OER) photo-electrocatalyst was examined. The composite would generate approximately three times larger steady-state photocurrents at 1.2 V vs. SCE in a neutral 0.5 M Na2SO4 electrolyte compared to WO3 alone. The surface recombination of photogenerated electron–hole pairs was characterized by intensity-modulated photocurrent spectroscopy (IMPS). Photogenerated charge transfer efficiencies were calculated from the spectra, and at 1.2 V vs. SCE, were 86.6% for WO3 and 62% for WO3-TiO2. Therefore, the composite films suffered from relatively more surface recombination but generated larger photocurrents, which resulted in overall improved photoactivity. [ABSTRACT FROM AUTHOR]

Zinc–nickel coatings based on the zinc-enriched gamma phase exhibit the maximum corrosion resistance and form the basis of the production of highly electrocatalytically active nanoporous nickel by selective dissolution. The electrodeposition of Zn–Ni alloys is the most widely used method of their preparation which proceeds by the mechanism of anomalous codeposition, where the deposition rate of the electropositive component (nickel) is lower as compared with the electronegative component (zinc). To obtain coatings of the particular morphology, chemical and phase composition, it is necessary to know the kinetics of the cathodic deposition of Zn–Ni alloys in the stage of heterogeneous nucleation, which is the goal of this study. The kinetics of this process is studied in non-stirred ammonium chloride electrolytes using the methods of cyclic voltammetry and chronoamperometry. The mechanism of heterogeneous nucleation at the electrodeposition of zinc and nickel is determined using the approach proposed by Palomar-Pardavé et. al which takes into account the contributions to the total cathodic current made by the parallel reaction of hydrogen reduction and the electric double layer charging. The nucleation mechanism for zinc–nickel coatings is described using the model of Scharifker–Hills for the electrodeposition of binary alloys additionally modified by taking into account the experimentally determined dependence of the composition of zinc–nickel coatings on the time in the stage of cathodic nucleation of the deposit. Using the method of energy-dispersive X-ray spectroscopy, the anomalous character of the deposition of Zn–Ni coatings is confirmed, where the ratio of atomic fractions Ni/Zn turns out to be lower than the ratio of concentrations of ions Ni2+/Zn2+ in the electrolyte. It is found that both during the electrodeposition of zinc and nickel from their individual solutions and during their anomalous codeposition, the nucleation rate constant increases with an increase in the cathodic potential but in average does not exceed 3 s–1, which points to the predominantly progressive nucleation. The growth of the new phase, regardless of its chemical composition, is limited by the 3D-diffusion of zinc and nickel ions to the electrode surface. The nucleation site density depends weakly on the deposition potential, decreasing with the transition from zinc to nickel and zinc–nickel alloys. As expected, the contribution of the side reaction of hydrogen reduction is the maximum for nickel electrocrystallization and decreases with the transition to Zn–Ni alloys and zinc, increasing with an increase in the cathodic potential, in agreement with the values of current efficiency. [ABSTRACT FROM AUTHOR]

Enhancing tribological performance through nanostructure control is crucial for saving energy and improving wear resistance for diverse applications. We introduce a new electrochemical approach that integrates aluminum (Al) anodization, tin alternating current (AC) electrodeposition, and anodic MoS2 electrosynthesis for fabricating nanostructured Al2O3/Sn(S)MoS2 composite films on AlSiCu casting alloys. Our unique process uses Sn‐modified MoS2 deposition to form robust solid lubricant MoS2–SnS electrodeposits within the nanochannels and microsized voids/defects of anodic alumina matrix films on the base materials, resulting in a bilayered Al2O3/SnSMoS2 and MoS2–SnS–Sn composite film. The AC‐deposited Sn enhances conductivity in the anodic alumina matrix film, acts as catalytic nuclei for Sn@SnS@MoS2 core‐shell nanoparticles and a dense top layer, and serves as a reductant for the direct synthesis of hybrid solid lubricant MoS2–SnS from MoS3 by anodic electrolysis of MoS42− ions. The resulting nanocomposite film provides a two‐fold increase in lubricity (friction coefficient (COF) μ = 0.14 ⇒ 0.07) and a ten‐fold improvement in wear resistance (COF μ < 0.2) compared to conventional Al2O3/MoS2 film formed by anodizing and reanodizing. The effectiveness of the Al2O3/Sn(S)MoS2 composite is further validated through real automotive engine piston tests. [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]

[Display omitted] Electrocatalytic nitrate reduction reaction presents a promising avenue for environmentally friendly ammonia (NH 3) synthesis and wastewater treatment. An essential aspect to consider is the meticulous design of electrocatalysts. This study explores the utilization of a Ni-Co alloy nanosheet-decorated three-dimensional titanium dioxide (3D-TiO 2) nanobelts electrodeposited on titanium meshes (Ni x Co y @TiO 2 /TM) for efficient electrocatalytic NH 3 production. The optimized Ni 1 Co 3 @TiO 2 /TM electrode achieves a significant NH 3 yield of 676.3 ± 27.1 umol h−1 cm−2 with an impressive Faradaic efficiency (FE) of 95.1 % ± 2.1 % in a 0.1 M KOH solution containing 0.1 M NO 3 − at −0.4 V versus the reversible hydrogen electrode. Additionally, the electrode demonstrates exceptional electrochemical activity for NH 3 synthesis in simulated wastewater, delivering an outstanding NH 3 yield of 751.6 ± 44.3 umol h−1 cm−2 with a FE of 96.8 % ± 0.4 % at the same potential of −0.4 V. Moreover, the electrode exhibits minimal variation in current density, NH 3 yields and FEs throughout the 24-h stability test and the 20-cycle test, demonstrating its excellent stability and durability. This study offers a straightforward electrodeposited approach for the development of 3D-nanostructured alloys as catalysts for NH 3 electrosynthesis from nitrates at room temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] Heteroatom-doped electrodes offer promising applications for enhancing the longevity and efficiency of vanadium redox flow battery (VRFB). Herein, we controllably synthesized N, P co-doped graphite fiber electrodes with conductive network structure by introducing protonic acid and combining electrodeposition and high temperature carbonization. H 2 SO 4 and H 3 PO 4 act as auxiliary and dopant, respectively. The synergistic effect between N and P introduces additional defect structures and active sites on the electrodes, thereby enhancing the reaction rate, as confirmed by density functional theory calculations. Furthermore, the conductive network structure of carbon fibers improves electrode-to-electrode connectivity and reduces internal battery resistance. The optimized integration of these strategies enhances VRFB performance significantly. Consequently, the N, P co-doped carbon fiber modified graphite felt electrodes demonstrate remarkably high energy efficiency at 200 mA cm−2, surpassing that of the blank battery by 7.9 %. This integrated approach to in-situ controllable synthesis provides innovative insights for developing high-performance, stable electrodes, thereby contributing to advancements in the field of energy storage. [ABSTRACT FROM AUTHOR]

The possibility of electrochemical deposition of tin‒bismuth alloy with an increased tin quota which is in demand for microassembly in electronics was revealed. Modification of the acid EDTA electrolyte with hydroxyl-containing surfactants differing in the length of hydrocarbon chain and the number of hydroxyl groups provided the deposition of Sn–Bi alloys with tin content 36.0–63.0 wt.%. in the presence of 1,4-butyndiol (BD), and up to 80.0 wt.% using polyvinyl alcohol (PVA-10) or a product of processing a mixture of alkylphenols with ethylene oxide (OP-10). The reasons for different surfactants action were found. PVA-10 and OP-10, unlike BD, slow down the diffusion of Bi(III) ions by 3‒4 times. All surfactants accelerate the diffusion of Sn(II) ions, which is especially noticeable in the case of BD. This effect of BD is due to its complexation with Sn(II) ions instead of EDTA, as a result of which the diffusion of positively charged particles to the cathode is accelerated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Critical design and exploration of perovskite photovoltaic-electrolysis for hydrogen production with superior STH efficiency. • Large-scale photovoltaic hydrogen production using perovskite solar module and earth-abundant catalysts. Harnessing the inexhaustible solar energy for water splitting is regarded one of the most promising strategies for hydrogen production. However, sluggish kinetics of oxygen evolution reaction (OER) and expensive photovoltaics have hindered commercial viability. Here, an adhesive-free electrodeposition process is developed for in-situ preparation of earth-abundant electrocatalysts on super-flat indium tin oxide (ITO) substrate. NiFe hydroxide exhibited prominent OER performance, achieving an ultra-low overpotential of 236 mV at 10 mA/cm2 in alkaline solution. With the superior OER activity, we achieved an unassisted solar water splitting by series connected perovskite solar cells (PSCs) of 2 cm2 aperture area with NiFe/ITO//Pt electrodes, yielding overall solar to hydrogen (STH) efficiency of 13.75 %. Furthermore, we upscaled the monolithic facility to utilize perovskite solar module for large-scale hydrogen production and maintained an approximate operating current of 20 mA. This creative strategy contributes to the decrease of industrial manufacturing expenses for perovskite-based photovoltaic-electrochemical (PV-EC) hydrogen production, further accelerating the conversion and utilization of carbon-free energy. [ABSTRACT FROM AUTHOR]