Bimetallic Electrode Research Articles

Bimetallic Cu-based hollow fibre electrodes for CO2 electroreduction

• Porous Cu-based hollow fibre electrodes were synthesised for CO 2 electroconversion. • Cu hollow fibres were functionalised with Au and Ni via electrodeposition technique. • Preliminary results in cell showed promising results in terms of Faraday efficiency. • This work may provide new insights for developing highly efficient electrocatalysts. The electrochemical reduction of CO 2 represents an attractive alternative to both, i) satisfy the increasing energy demand, and ii) to help closing the carbon cycle. However, the energy required for CO 2 activation and the subsequent required multiple number of proton-coupled electron transfer steps, makes this process very challenging. Besides, catalytic material limitations hamper the application of this technology in the short term. Consequently, in this work we synthesise, characterise and preliminarily evaluate bimetallic Cu-based hollow fibre electrodes with a compact three-dimensional geometry to overcome mass transfer limitations and to enhance the electrochemical conversion of CO 2 . The Cu hollow fibres are functionalised with Au in an attempt to tune the binding energy of the CO* intermediate, which appears to be key in the reduction of CO 2 . The Cu fibres are also functionalised with Ni, aiming to decrease the reaction overpotential, resulting in beneficial energy efficiency. The so prepared Cu-based porous hollow fibre electrodes are obtained by dry-wet spinning and electrodeposition procedures. The materials are then characterised by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction analyses and cyclic voltammetry. Finally, preliminary results of CO 2 electroreduction in a divided three-electrode cell are reported. The results show the potential of highly active, bimetallic hollow fibre-based electrocatalysts for enhanced conversion of CO 2 into value-added products. Deposition of particles should be performed with care, not to affect pore characteristics and thus mass transfer properties.

Single Pt-Pd Bimetallic Nanoparticle Electrode: Controllable Fabrication and Unique Electrocatalytic Performance for the Methanol Oxidation Reaction.

Understanding the electrocatalytic activity at single nanoparticles/nanoclusters level is extremely important. In this work, a method for the electro-deposition of single Pt-Pd nanoparticles (NPs) is described using a single nanopore electrode as a template. The electro-deposition process was investigated carefully and the results show that the process is controlled by diffusion and electro-crystallization process, simultaneously, and the glass sheath property around the nanopore has a large impact on the formation of single Pt-Pd NPs due to the "edge effect". The prepared single Pt-Pd NPs exhibit excellent electrocatalytic activity in the methanol oxidation reaction, which can be used to screen electrocatalysts with high efficiency for utility in the energy field.

Selective Deposition of Metals onto Molecularly Tethered Gold Nanoparticles: The Influence of Silver Deposition on Oxygen Electroreduction

Multimetallic nanoparticles (NPs) are being explored for their promising electrocatalytic properties that arise from synergistic interactions between multiple metals on the nanoscale. Despite the promising properties of these materials, it is still not fully understood how various attributes of a multimetallic NP electrocatalyst (i.e., composition, structure, and interface to an electrode) contribute to its electrocatalytic activity due to the lack of fabrication methods that allow subnanometer control over these variables. We developed an approach to construct bimetallic nanoparticle-functionalized electrodes in situ through the selective deposition of a second metal onto the surface of gold or silver nanoparticles previously bound to a boron-doped diamond electrode through a molecular interface. We used this approach to investigate the role of bimetallic composition and structure of silver–gold nanoparticle (Ag–AuNP) electrocatalysts on the oxygen reduction reaction (ORR) in alkaline media. This method ...

Fabrication and characterization of a Ni-TNTA bimetallic nanoelectrode to electrochemically remove nitrate from groundwater

A novel Ni-TiO2 nanotube array (Ni-TNTA) bimetallic nanometer electrode was developed. The electrode fabrication method was optimized, and the Ni-TNTA bimetallic nanoelectrode was used to efficiently remove nitrate from groundwater. The Ni-TNTA bimetallic nanoelectrode was prepared via an electrochemical method, chemical bath deposition method and calcining method. When the current density was 30 mA cm−2 after 90 min of electrolysis, the removal rate of nitrate was as high as 93.4%, whereas the removal rate of a TiO2 nanoelectrode made via the traditional method was only 56.0%. Under the same conditions, the newly developed Ni-TNTA bimetallic nanoelectrode increased the removal rate of nitrate by 66.8%. The results showed that the removal rate of nitrate was the highest when the Ni-TNTA bimetallic nanoelectrode was prepared with a 10 min chemical bath and calcination at 500 °C. The effect of the electrode on the removal rate of nitrate was investigated for different current densities, initial concentrations, temperature and pH. When the solution was alkaline, the removal efficiency of nitrate improved. When the current density and temperature increased, the removal rate of nitrate accordingly increased. However, as the initial concentration of the solution increased, the removal rate of nitrate decreased. An IrO2 electrode was used as the anode, the Ni-TNTA bimetallic nanoelectrode was used as the cathode, and 0.3 g L−1 NaCl was added into the solution. The removal rate of nitrate was 89.6% after 90 min of electrolysis and barely produced nitrite or ammonia.

Facile fabrication of a flexible electrode by electrodeposition of palladium on silver nanowires for ethanol oxidation

Currently, most of the working electrodes in electrochemistry are fabricated on rigid substrates. However, flexible electrodes may play important roles in future electronics, such as wearable medical devices and fuel cells. In this study, a flexible Pd/AgNWs/PDMS electrode was generated by the electrodeposition of palladium (Pd) onto silver nanowires (AgNWs), which were drop-casted on polydimethylsiloxane (PDMS). Scanning electron microscopy (SEM) results showed that the AgNWs or the Pd coated AgNWs distributed evenly on the PDMS substrates. In addition, Pd nanoparticles were uniformly deposited on the AgNWs and the amount of the Pd nanoparticles on the AgNWs gradually increased along with the increasing deposition time. When this flexible electrode was used as the working electrode in a three-electrode system for ethanol oxidation in alkaline media (0.1 M KOH), the results showed that the electrode deposited for 25 CV cycles performed the best in 1.0 M ethanol, exhibiting large electrochemical active surface area (ECSA, 17.05 m2 g−1), more negative onset potential (−0.60 V, vs. Ag/AgCl), lower peak potential (0.56 V, vs. AgNWs), and enhanced charge transfer by electrochemical impedance spectroscopy (EIS). The new facile method for the construction of this bimetallic flexible catalytic electrode may inspire interesting applications in electrochemistry.

Electrochemical analysis of Na-Ni bimetallic phosphate electrodes for supercapacitor applications.

Bimetallic sodium–nickel phosphate/graphene foam composite (NaNi4(PO4)3/GF) was successfully synthesized using a direct and simple precipitation method. The hierarchically structured composite material was observed to have demonstrated a synergistic effect between the conductive metallic cations and the graphene foam that made up the composite. The graphene served as a base-material for the growth of NaNi4(PO4)3 particles, resulting in highly conductive composite material as compared to the pristine material. The NaNi4(PO4)3/GF composite electrode measured in a 3-electrode system achieved a maximum specific capacity of 63.3 mA h g−1 at a specific current of 1 A g−1 in a wide potential range of 0.0–1.0 V using 2 M NaNO3 aqueous electrolyte. A designed and fabricated hybrid NaNi4(PO4)3/GF//AC device based on NaNi4(PO4)3/GF as positive electrode and activated carbon (AC) selected as a negative electrode could operate well in an extended cell potential of 2.0 V. As an assessment, the hybrid NaNi4(PO4)3/GF//AC device showed the highest energy and power densities of 19.5 W h kg−1 and 570 W kg−1, respectively at a specific current of 0.5 A g−1. The fabricated device could retain an 89% of its initial capacity with a coulombic efficiency of about 94% over 5000 cycling test, which suggests the material's potential for energy storage devices applications.

Metal oxide-based supercapacitors: progress and prospectives.

Distinguished by particular physical and chemical properties, metal oxide materials have been a focus of research and exploitation for applications in energy storage devices. Used as supercapacitor electrode materials, metal oxides have certified attractive performances for fabricating various supercapacitor devices in a broad voltage window. In comparison with single metal oxides, bimetallic oxide materials are highly desired for overcoming the constraint of the poor electric conductivity of single metal oxide materials, achieving a high capacitance and raising the energy density at this capacitor-level power. Herein, we investigate the principal elements affecting the properties of bimetallic oxide electrodes to reveal the relevant energy storage mechanisms. Thus, the influences of the chemical constitution, structural features, electroconductivity, oxygen vacancies and various electrolytes in the electrochemical behavior are discussed. Moreover, the progress, development and improvement of multifarious devices are emphasized systematically, covering from an asymmetric to hybrid configuration, and from aqueous to non-aqueous systems. Ultimately, some obstinate and unsettled issues are summarized as well as a prospective direction has been given on the future of metal oxide-based supercapacitors.

A non-noble bimetallic alloy in the highly selective electrochemical synthesis of the biofuel 2,5-dimethylfuran from 5-hydroxymethylfurfural

2,5-Dimethyl-furan (DMF) was electrochemically synthesized from 5-hydroxymethylfurfural with high efficiency and selectivity using a CuNi bimetallic electrode.

Suppression of Competing Reaction Channels by Pb Adatom Decoration of Catalytically Active Cu Surfaces During CO2 Electroreduction

The direct electrochemical conversion of carbon dioxide to chemicals and fuels is of fundamental scientific and technological interest. The control of the product selectivity, expressed in terms of the Faradaic efficiency, has remained a great challenge. Herein, we describe a surface-electrochemical synthetic strategy to tune the electrochemical CO2 reduction selectivity and yield by controlled suppression of the hydrogen evolution reaction (HER) reaction channel, resulting in increased Faradaic efficiencies for fuels and chemicals. We demonstrate that bimetallic catalysts consisting of only minute submonolayer amounts of Pb adatoms deposited on Cu surfaces exhibit and maintain unusually high selectivities for formate (HCOO–) over a large range of overpotentials. The bimetallic adatom electrodes were prepared using underpotential electrodeposition (UPD), which is able to precisely control the adatom coverage. While as little as 0.16 ML Pb surface adatoms on a polycrystalline Cu surface boosted the observed Faradaic HCOO– product selectivity 15 times, the 0.78 ML Pb/Cu catalyst showed the most favorable ratio of HCOO–/H2 production rate thanks to the effective suppression of the HER combined with a partial (−1.0 to −1.1 V vs RHE) enhancement of the HCOO– production. We argue that the favorable product efficiency is caused by selective adatom poisoning on the strongest binding hydrogen adsorption sites; in addition, electronic effects of Pb adatoms change the chemisorption of reactive intermediates. Our study reveals synthetic access to tailored selective bimetallic copper catalysts for the electrochemical CO2 reduction and demonstrates the enormous effect of even minute amounts of surface adatoms on the product spectrum.

Hydrogen oxidation kinetics on platinum-palladium bimetallic thin films for solid acid fuel cells

Solid acid fuel cells (SAFCs) based on the proton-conductive electrolyte CsH2PO4 have shown promising power densities at an intermediate operating temperature of ∼250 °C. However, Pt loadings in SAFCs remain higher than desirable, and the electrocatalysis mechanisms in these devices are still unknown. Here, hydrogen oxidation kinetics on Pt and Pt-Pd bimetallic thin film electrodes on CsH2PO4 have been evaluated to establish the potential for a beneficial role of Pd in SAFC anodes. Symmetric cells fabricated by depositing a metal film on both sides of electrolyte discs are characterized for studying hydrogen electro-oxidation across the gas|metal|CsH2PO4 structure. It was found that Pd reacts with CsH2PO4, forming palladium phosphide at the metal-electrolyte interface. Accordingly, the activity of Pd was examined in a bilayer geometry of Pd|Pt|CsH2PO4|Pt|Pd. The bilayer Pt|Pd films showed much higher activity for hydrogen electro-oxidation than films of Pt alone, as measured by AC impedance spectroscopy. Ex situ low energy ion scattering and scanning transmission electron microscopy revealed that Pd diffused into the Pt layer under operating conditions. The dramatic impact of Pd along with its presence throughout the film suggests that it catalyzes reactions at both the metal-gas and metal-electrolyte interfaces, as well as increasing hydrogen diffusion rates through the films.

Ag-Cu bimetallic nanoparticle decorated graphene nanocomposite as an effective anode material for hybrid capacitive deionization (HCDI) system

An effective battery electrode material with a good capacitance and excellent conductivity is highly demanding for the hybrid capacitance deionization (HCDI) application. Bimetallic nanoparticles (NPs) decorated graphene composites have received significant attention, and it might improve the storage space and the conductivity of the electrode material. Herein, we used bimetallic silver (Ag) - copper (Cu) decorated graphene (ACG) nanocomposite as the anode electrode material for the HCDI application and studied its deionization performance. Also, the HCDI performance of the ACG has been compared with monometallic Cu-doped graphene (CG) and Ag-doped graphene (AG) nanocomposites. Both the bimetallic and monometallic nanocomposites have been generated by a facile thermal treatment method. X-ray photoelectron spectroscopy (XPS) analysis confirmed the existence of Cu and Ag nanoparticle in the graphene nanostructure with the +2 and 0 oxidation states respectively. Transmission electron microscopy (TEM) analysis displays the uniform distribution of nanoparticles with both phases of Cu and Ag on the graphene sheets and the size of around 20–60 nm. Electrochemical measurements showed that the ACG exhibits the good specific capacitance of 128 Fg−1 as compared to monometallic AG and CG composites of 118 Fg−1 and 101 Fg−1 respectively. Furthermore, the HCDI measurements reveal that the ACG nanocomposite electrode showed the salt adsorption capacity (SAC) of 16.81 mg g−1 with initial salt concentration of 600 ppm, and the applied voltage of 1.2 V. Besides, the ACG based HCDI cell possessed the charge efficiency of 90% and the energy consumption of 88 kJ mol−1 at 1.2 V. Also, the ACG nanocomposite electrode showed good stability regeneration ability over 10 charge− discharge cycles. The present study introduced the developed bimetallic graphene composite electrodes as effective electrodes for HCDI technology.

Synthesizing nickel-based transition bimetallic oxide via nickel precursor-free hydrothermal synthesis for battery supercapacitor hybrid devices

The Ni foam can act as the nickel ion source and the current collector for synthesizing Ni-based compounds using the hydrothermal synthesis especially in the acid condition. Using Ni foam as the Ni2+ source can grow materials on the substrate directly and uniformly since nickel ions are released from substrate thoroughly. Nickel-based bimetallic oxides are intensively investigated as battery-type materials for battery supercapacitor hybrid devices (BSHD) because of high electrical conductivities and abundant transition states for inducing multiple redox reactions. In this study, Mo, Mn, Al, and W precursors are simply added in Ni precursor-free acid solution for hydrothermal synthesis using Ni foam as the nickel ion source and the current collector to synthesize Ni-based bimetallic oxide electrodes for BSHD. The morphology of nickel-based bimetallic oxide prepared with and without incorporating the structure-directing agent is also carefully discussed. The highest specific capacitance (CF) of 1.80 F/cm2 corresponding to the capacity of 4.54 mAh/cm2 at 5 mA/cm2 is attained for the nickel molybdenum oxide (Ni-Mo oxide) electrode. The Ni-Mo oxide-based BSHD shows a potential window of 1.8 V, a CF value of 223.53 mF/cm2 corresponding to the capacity of 1.45 mAh/cm2 at 5 mA/cm2, the maximum energy density of 4.60 Wh/kg at the power density of 0.21 kW/kg, and the CF retention of 90% after 6000 times charging/discharging process.

Strong physisorption and superb thermal stability of carbon nanofibers carried CuxO-V2O5 enabling the flexible and long-cycling supercapacitor

Carbon nanofibers supported the vanadium and copper bimetallic oxide composite electrode material has been developed successfully in this study, as the outstanding electrode materials in supercapacitors. In electrospunning and calcination processes, the organic salt of vanadium underwent high temperature decomposition to form V2O5 in situ. The various ratios of CuxO-V2O5/CNFs composite electrode material were used to apply in the electrochemical performance testing through the vacuum impregnation method. Because of the copper doping, CuxO-V2O5/CNFs (10:1) composites exhibited a specific capacitance of 867.2 F g−1 at 0.5 A g−1 over a potential range of 0–0.51 V, which surpassed those of their individual counterparts (682.5 F g−1 and 507.1 F g−1 at 0.5 A g−1 for V2O5/CNFs and CuCl2/CNF, respectively). The addition of trace copper oxide greatly improves the electrochemical performance of vanadium-based carbon fibers composites. The composites also showed good cycling stability due to the unique structure of the V2O5 and synergies with copper oxide. The preparation route provided a novel strategy to synthesize composites of transition bimetallic oxide with improving electrochemical performance for applications in supercapacitors.

Electrochemical reduction of nitrate via Cu/Ni composite cathode paired with Ir-Ru/Ti anode: High efficiency and N2 selectivity

To address the severe nitrate contamination of water sources, a Cu/Ni bimetallic composite electrode was successfully prepared via cathodic electrodeposition method. Characterization by scanning electron microscopy, energy-dispersive spectroscopy, and X-ray diffraction confirmed that Cu nanoparticles were successfully deposited on the surface of Ni foam as irregular spherical structures with a diameters of 900 nm. The Cu/Ni electrode was applied as a cathode in nitrate electroreduction experiments, achieving nearly complete removal of nitrate within 60 min compared to a Ni foam electrode (15.0% removal). The improved performance was attributed to the dramatically increased catalytically active sites and the decreased resistance of the electrode, as shown by linear sweep voltammetry and electrochemical impedance spectroscopy analyses. The parameters influencing electrolysis, including current density, Cl− concentration, and solution pH were evaluated. It was concluded that (a) Increasing the current density favored nitrate removal, but reduced the electronic energy utilization efficiency; (b) Cl− presence hindered nitrate removal slightly, but facilitated NH4+-N removal significantly; (c) Acidic conditions were detrimental to nitrate and total nitrogen removal. Additionally, reusability experiments of the Cu/Ni electrode over eight cycles were performed. These indicated that the Cu/Ni electrode possessed excellent stability, maintaining a high removal efficiency of >95.0% over eight cycles. Finally, a possible removal pathway of nitrate electroreduction with the Cu/Ni cathode was proposed.

Enhanced cycle stability of a NiCo2S4 nanostructured electrode for supercapacitors fabricated by the alternate-dip-coating method.

Nanostructured nickel cobalt sulfide (NiCo2S4) electrodes are successfully fabricated using a simple alternate-dip-coating method. The process involves dipping a TiO2 nanoparticles-covered substrate in a nickel/cobalt precursor solution and sulfur precursor solution alternately at room temperature. The fabricated bimetallic sulfide electrode exhibits a synergetic improvement compensating for the disadvantages of the two single metal sulfide electrodes, i.e. the poor cycle stability of the nickel sulfide electrode and the low specific capacitance (Csp) of the cobalt sulfide electrode. The two capacitive properties are optimized by adjusting the ratio of nickel and cobalt concentrations in the metal precursor solution, reaching a Csp of 516 F g−1 at a current density of 1 mA cm−2, with its retention being 99.9% even after 2000 galvanostatic charge–discharge cycles.

Mesoporous Mn-Sn bimetallic oxide nanocubes as long cycle life anodes for Li-ion half/full cells and sulfur hosts for Li-S batteries

Mesoporous Mn-Sn bimetallic oxide (BO) nanocubes with sizes of 15–30 nm show outstanding stable and reversible capacities in lithium ion batteries (LIBs), reaching 856.8 mAh·g–1 after 400 cycles at 500 mA·g–1 and 506 mAh·g–1 after 850 cycles at 1,000 mA·g–1. The preliminary investigation of the reaction mechanism, based on X-ray diffraction measurements, indicates the occurrence of both conversion and alloying–dealloying reactions in the Mn-Sn bimetallic oxide electrode. Moreover, Mn-Sn BO//LiCoO2 Li-ion full cells were successfully assembled for the first time, and found to deliver a relatively high energy density of 176.25 Wh·kg–1 at 16.35 W·kg–1 (based on the total weight of anode and cathode materials). The superior long-term stability of these materials might be attributed to their nanoscale size and unique mesoporous nanocubic structure, which provide short Li+ diffusion pathways and a high contact area between electrolyte and active material. In addition, the Mn-Sn BOs could be used as advanced sulfur hosts for lithium-sulfur batteries, owing to their adequate mesoporous structure and relatively strong chemisorption of lithium polysulfide. The present results thus highlight the promising potential of mesoporous Mn-Sn bimetallic oxides for application in Li-ion and Li-S batteries.

Methanol oxidation on Ru/Pd(poly) in alkaline solution

Polycrystalline Pd electrode, Pd(poly), is modified by Ru nanoislands using spontaneous deposition method. Coverage of Pd(poly) electrode with the deposited Ru are approx. 20, 30 and 50% as estimated from phase atomic force microscopy images. The oxidation state of Pd substrate and the deposited Ru is determined by X-ray spectroscopy (XPS). Electrocatalytic activity of obtained Ru/Pd(poly) bimetallic electrodes is tested towards methanol oxidation in alkaline medium. Cyclic voltammetry and chronoamperometry experiments show the enhanced activity of Ru/Pd(poly) electrodes towards methanol electrooxidation with respect to bare Pd(poly). This is explained by the presence of Ru islands, which provided RuOH and Pd-RuOH sites, necessary for the oxidation of CO as the main intermediate during the oxidation of methanol at lower potentials. 30% Ru/Pd(poly) is the most active of all examined electrodes.

Carbon-nanotube-doped Pd-Ni bimetallic three-dimensional electrode for electrocatalytic hydrodechlorination of 4-chlorophenol: Enhanced activity and stability

A novel composite bimetallic electrode, palladium-nickel/multi-walled carbon nanotubes/graphite felt (Pd-Ni/MWCNTs/GF), was synthesized for the electrocatalytic hydrodechlorination of 4-chlorophenol (4-CP). GF with a three-dimensional structure was used as the electrode substrate, and doped with MWCNTs, which can improve the GF conductivity and serve as a skeleton for metal loading. Ni and Pd were deposited on the electrode surface stepwise to obtain a well-aligned, highly active and stable Pd-Ni/MWCNTs/GF electrode. The Pd-Ni/MWCNTs/GF cathode showed a high reactivity for the electrocatalytic hydrodechlorination of 4-CP; up to 100% removal of 4-CP was achieved within 30 min, and followed pseudo-first-order kinetics with a rate constant of 0.162 min−1. Compared with other cathodes, the Pd-Ni/MWCNTs/GF electrode showed superior performance in 4-CP reduction. Excessive current will lower the reaction efficiency and current efficiency because of hydrogen evolution, and acidic solution conditions are more conducive to electrocatalytic reactions. Experiments confirmed that the Ni had a small amount of loss under acidic conditions but remained stable under neutral and alkaline conditions, whereas the loss of Pd for different pH values was constantly low. In cycle tests, the bimetallic electrode exhibits a better reactivity and stability than the single-metal Pd electrode in the long-term.

Perchlorate catalysis reduction by benzalkonium chloride immobilized biomass carbon supported Re-Pd bimetallic cluster particle electrode

This work had demonstrated a novel and high-efficiency perchlorate reduction particle electrode using benzalkonium chloride as dynamics strengthener and coupling with rhenium (Re) and palladium (Pd) nanoparticles (Re-Pd/BC). Perchlorate ions could be rapidly adsorbed in the presence of benzalkonium chloride, facilitating its subsequent reduction on the Re-Pd/BC particle electrode. On the basis of the characterization results and kinetics analysis, a synergistic effect of Re and Pd was observed, perchlorate could be efficiently reduced and completely converted into chlorine in optimized conditions (pH 3.0, anaerobic and current density 20 mA/cm2) and the reduction rate constant of Re-Pd/BC was 0.9451 L−1 gcat−1. The superfluous oxygen in solution could lead to Re-Pd/BC deactivation, and increased current density was beneficial of electro-reduction. The increased pH lead to decrease of reduction efficiency, and the coexisting anion of nitrate could be competed with perchlorate for reduction sites which lead to decrease of reduction rate. Based on the experimental results, it was found that the existing form of Re and Pd on the surface of Re-Pd/BC, the number of atomic H∗ and current density played an important role in perchlorate electro-reduction process.

Electrochemical fabrication of dendritic silver–copper bimetallic nanomaterials in protic ionic liquid for electrocarboxylation

Silver (Ag) and silver–copper (Ag–Cu) bimetallic composite electrodes were electrochemically prepared on a glassy carbon (GC) substrate in triethylammonium acetate (TEAA) by electrodeposition to investigate their suitability as cathodes for electrocarboxylation process. Cyclic voltammetric investigations reveal that with increase in Cu content, both the stripping as well as deposition current of Ag (I) ions decrease with a shift of cathodic and anodic peak potential in the positive side, where the onset deposition potential difference between Cu and Ag ions becomes less, favouring effective co-deposition of both ionic species. The morphologies of deposits change significantly from cubic structure to flower-shaped dendrites by the incorporation of more amount of Cu, as noted from scanning electron microscopy (SEM) images. Crystallographic (XRD) analysis confirms the formation of Ag–Cu co-deposits and the compositions of the different deposits were found out using atomic absorption spectroscopy (AAS). The Ag–Cu composite containing 23% of Cu (Ag77–Cu23) shows the highest cathodic potential window in N,N-dimethylformamide/tetrabutylammonium tetrafluoroborate (DMF/TBABF4) medium. Further, Ag77–Cu23 shows higher reductive current on the electroreduction of benzophenone in presence and absence of carbon dioxide than that of other Ag based composite electrodes resulting in an enhancement of the product yield.