Mechanism Of Electrochemical Deposition Research Articles

Microstructure and Properties of Porous Copper Foils with High Specific Surface Area Prepared by Electrodeposition

The high surface area porous copper foils are synthesized on commercial copper foils by dynamic hydrogen bubble template electrodeposition method. The electrochemical deposition mechanism of porous copper foils and the current density on the structure formation mechanism are explored. The results show that under the conditions of stable electrolyte, electrodeposition time of 20 s, and current density of 2 A·cm−2, the microporous distribution of the deposited layer is uniform and the adhesion between the pore walls is strong. Compared with the planar copper foil, the porous copper foil possesses the “large on top and small on bottom” porous structure, which significantly improves the specific surface area of the copper foil, and the resistance value decreases by 43.1%. The electrochemical test results show that the performance of the porous collector is significantly better than that of the planar collector. Furthermore, the porous copper collector has a lower charge transfer impedance (150 Ω). The results of this paper provide an innovative strategy for the preparation of porous collectors and for solving the problem of lithium metal batteries.

Direct Electrochemical Extraction of Sm from SmCl3 in a Molecular Liquid Solvent Supported By LiNO3

Low-temperature electrochemical extraction of rare earth metals from their corresponding chlorides in ionic liquids has long been a scientific challenge. In this study, a new class of task-specific ionic liquids (ILs) containing Li elements, i.e. Li-containing solvate ionic liquids ([Li(DMI)n]3+NO3 —, 0.15 M LiNO3 dissolved in DMI (1,3-Dimethy-l-2-imidazolidinone)), is developed and used for metallic Sm electrodeposition from SmCl3. To elucidate the electrochemical deposition mechanism, the ionic component of the DMI/LiNO3 system was characterized by a range of instrumental analysis techniques (including 7Li NMR, UV-vis) and theoretical calculations. Cyclic voltammetry was used to explore the electrochemical behavior of Sm-containing species in the ionic liquid. Finally, metallic Sm was successfully obtained using constant potential deposition on high purity Al substrates which was confirmed by XPS and SEM. Li-containing solvate ILs have immense potential in green electrometallurgy because of their higher tunability and similar properties to ILs.

On the mechanism of electrochemical deposition of graphene on Al foils and AlSi10MgCu particles

The graphene synthesis via the electrochemical method and electrochemical deposition of graphene on Al foils and AlSi10MgCu particles were studied. The thickness of deposited graphene layers was varied from 3 to 20 layers and, thus, they were classified as multi-graphene. The chemically pure sucrose C12H22O11 was used as a raw material for graphene synthesis. It was shown that the deposition of graphene layers was affected mainly by the pH values of electrolyte mediums. In the electrochemical reaction at H2SO4 water solution at pH < 7, the graphene was deposited on Al foils and on AlSi10MgCu particles from the electrolyte. The microstructure and composition of graphene formed on Al foils and AlSi10MgCu particles' surface were studied by Raman spectroscopy, SEM, EDX, and TEM methods. The chemical mechanism of graphene formation was defined as follows: the sucrose was recovered via the reaction route C12H22O11 → C6H12O6 → Cgraphene in acidic aqueous media. An increase in the H2SO4 concentration from 0.05 M to 0.80 M has resulted in the formation of graphene layers with up to 6 μm thickness on AlSi10MgCu particles.

Changes in the interfacial charge-transfer resistance of Mg metal electrodes, measured by dynamic electrochemical impedance spectroscopy

The interfacial electrochemical characteristics of unpassivated Mg metal electrodes have been studied using Staircase Galvano Electrochemical Impedance Spectroscopy (SGEIS) in THF/C6H5MgCl/AlCl3 solutions over a wide range of applied dc currents. The results shed light on the mechanism of electrochemical deposition and dissolution of Mg. We found that at the stationary condition (at the OCV, when no current flows) there is a very high interfacial charge-transfer resistance of around 40,000 Ωcm2. The impedance decreases to several hundred Ωcm2 when dynamic, though steady, processes of Mg deposition or dissolution take place. The alternating process through which impedance spectroscopy is measured is superimposed on this system. We show that the high impedance measured at the OCV with a low direct current is due to interfacial adsorption phenomena. However, the adsorption phenomena affect the interfacial charge transfer in different ways depending on the direction of the reaction. During steady-state deposition, the adsorbed layer leads to a large distance for electron tunneling, which translates to a high charge-transfer impedance across the interface. Application of relatively large steady-state negative currents leads to changes in the composition of the adsorbed layer and a significant reduction in the charge-transfer resistance. During the opposite process, dissolution, the high interfacial impedance measured is probably predominantly due to migration of Mg ions away from the Mg metal surface, across the adsorbed layer, to the bulk solution. At relatively high direct currents (and overpotentials >100 mV) the interfacial resistivity obeys Butler–Volmer kinetics, which are not complicated by adsorption phenomena.

Electrochemical deposition mechanism of sodium and potassium

Sodium and potassium metal batteries are being developed and studied enthusiastically by researchers, but the electrochemical deposition mechanism of sodium and potassium are still elusive and considered as analogs of the lithium version. In this study, it is found that the deposition of sodium and potassium are different from lithium. During deposition, cations get electrons and turn into metal deposited beneath the solid electrolyte interphase (SEI), and consequently the SEI is subject to the pressure from the metal around the deposition sites. Under the pressure, the SEI of lithium is strong enough to keep its integrity, which leads to the root growth of deposits. The lithium deposits are whiskers with the diameter of submicrometer and can be blocked by separators with the pores of dozens of nanometers. By contrast, the SEIs of sodium and potassium are weak and break into fragments under the pressure, and the subsequent deposition occur on the metal surfaces. The deposits grow into micro-scale granules and spread through the nanopores of separators, which causes the short circuit.

Electrochemical Deposition of CoNiFe Alloy from Concentrated Chloride Electrolyte

Heating the chloride electrolyte to a temperature of 70 °C at the concentration ratio of CCo:CNi:CFe 1:1:1 provides stabilization of electrochemical deposition of the CoNiFe alloy components as a result of discharge of metal ions (Fe2+ Cl- )+ , (Со2+ Cl- )+ , (Ni2+ Cl- )+. Electrolyte filtering and correcting pH with HCl provides a reproducible deposition of CoNiFe films. Based on the experimental results of the CoNiFe films, a mechanism of electrochemical deposition is proposed, which differs in view of the phenomena occurring in the volume of electrolyte: mass draft ions, with the determining effect of mobility and the formation of positive ions on the anode. CoNiFe films are produced without mechanical stresses, with a uniform structure and with high magnetic parameters without high heat firing.

Mechanism of the Electrochemical Deposition of a CoNiFe Alloy

Heating the chloride electrolyte to a temperature of 70°C ensures the normal codeposition of the components of the CoNiFe alloy as a result of the discharge of single-charged iron and cobalt species (Fe2+Cl-)+ and (Co2+Cl-)+, respectively and double-charged Ni2+ ions at a high cathode current density. The chloride electrolyte obtained with filtration and pH correction by hydrochloric acid provides the electrochemical deposition of CoNiFe films with a CCo:CNi:CFe ratio of 1:1:1. The mechanism of the abnormal deposition of Co, Fe and Ni occurs due to the incomplete ionization of atoms and differences in ion mobility. Based on the experimental results of CoNiFe films, an electrochemical deposition mechanism is proposed. In contrast to the well-known in the literature, the phenomena occurring in the volume of electrolyte, including transmission of ions, with the determining effect is the mobility and formation of positive ions on the anode. CoNiFe films are produced without mechanical stresses, with a uniform structure and with high magnetic parameters without a high burn temperature. Electrochemical deposition when the charge of ions in the electrolyte is taken into account allows to obtaining a reproducible electrochemical deposition of CoNiFe films.

Electrochemical deposition mechanism of copper-zinc-tin alloy and structural characterization

The electrodeposition of Cu-Sn-Zn coating (CZT) was investigated. The bath consisted of aqueous solution of Cu, Sn and Zn sulphate in the presence of sodium citrate (NaC6H5Na3O7) as complexing agent. The pH was set between 4 and 5.5 to stabilize the bath. Cyclic voltammetry exhibited four peaks during cathodic scan corresponding to the reductions of metal ions and adsorbed hydrogen. Impedance measurements were made at each potential peak. The effect of the metal salts concentration and the potential scan rate were studied. The deposit mechanism is controlled by mass transfer in parallel with a faradaic reaction. For the deposition of Cu-Sn and Cu-Sn-Zn alloys, the average diffusion coefficients of Cu2+ and Sn2+ ions and Cu2+, Sn2+ and Zn2+ ions were calculated. At E = -1.5 V, a Cu-Sn-Zn deposit is obtained with 55 at% copper, 25 at% tin and 20 at% zinc. The X-ray diffraction pattern shows the characteristic peaks of Cu, Cu6Sn5 and Cu3Zn2 phases. The deposit morphology was characterized by SEM.

Preparation of lithium iron phosphate composites by electrodeposition with a tunnel structure on aluminium foil surface

In this paper, aluminium foil with a tunnel structure was used as a cathode to prepare a lithium iron phosphate composite by electrochemical deposition using propylene carbonate as the electrolyte solvent, and lithium nitrate, ferric nitrate and phosphoric acid as raw materials. The results show that the positive electrode composite is composed of a mixture of an olivine structured LiFePO4 and polyanion Li9Al3P8O29. The chemical composition of the mixture is related to the voltage of the electrochemical deposition and the acidity of the electrolyte solution. For a voltage of 1.8V and pH of 1.0, the composite material deposited in the tunnel of the aluminium foil takes the form of a one-dimensional nanotube, with a particle size ranging from 80nm to100nm. The composite material is closely combined with the aluminium foil. The aluminium foil can be directly used as a positive current collector, with a lithium sheet as the negative electrode. After mounting into a battery, an electrochemical performance test is performed. The battery test results show an initial discharge capacity of 95mAh/g, 79mAh/g and 59mAh/g at 0.1C, 0.2C and 0.5C, respectively. After the material is doped with magnesium and cobalt, the initial discharge capacity of the battery is 100mAh/g and 130mAh/g, respectively, at a rate of 0.1C. The cyclic voltammetry analysis of the battery show that after electrochemical deposition of the element, the symmetry between the oxidation and reduction peaks is increased, and the difference between the oxidation and reduction peak potentials is reduced. Element doping improves battery cycle performance. The AC impedance analysis show that the embedding impedance for lithium ions at the SEI interface is reduced from 300Ω to 250Ω, 100Ω after doping with magnesium, and cobalt. And the reaction mechanism of electrochemical deposition is discussed.

Growth mechanism during the early stages of electrodeposition of bismuth telluride Bi2Te3 on ITO substrate

The electrochemical deposition mechanism of Bismuth telluride (Bi2Te3) by co-reduction of the telluryl (HTeO2+) and bismuth ions from the nitric acid medium on tin doped indium oxide (ITO) substrate was investigated using two electrochemical techniques: cyclic voltammetry (at different scan rates) and chronoamperometry (at different applied potentials). The thin films electrodeposited by chronoamperometry were characterized by X-Ray diffraction (XRD) and UV–Visible spectroscopy, the exploitation of UV–visible curves allowed us to calculate the gap energy. Surface morphology was examined using a scanning electron microscope (SEM) and atomic force microscope (AFM). These techniques have shown that the electrodeposition of Bi2Te3 has been performed at a negative potential around −0.18 V vs SCE, with a quasi-reversible reaction controlled by the diffusion process. Moreover, the measured current transient curves were compared to those calculated from Scharifker-Hills models. It was found that a progressive 3D nucleation mechanism governs the nucleation and growth of Bi2Te3 on ITO substrate.

Nucleation and growth mechanism of tellurium electrodeposited on tin-doped indium oxide substrate

The mechanism of electrochemical deposition of tellurium on tin-doped indium oxide (ITO) substrate from a nitric acid solution containing telluryl ion (HTeO2+) has been studied in this work. The investigation, using cyclic voltammetry and chronoamperometry, shows that the electrodeposition of Te at a negative potential around − 0.42 V versus saturated calomel electrode (SCE) is a quasi-reversible reaction controlled by the diffusion process. Furthermore, by chronoamperometry, the measured current transient curves were compared with the theoretical models, proposed by Scharifker–Hills and Heerman–Tarallo models. It was found that the nucleation and growth mechanism of Te on ITO substrate changed with increasing the concentration of HTeO2+, it can be instantaneous for 2.10−2 mol L−1 or progressive for 2.10−3 mol L−1. The quantitative analysis (nonlinear fitting) shows that the diffusion coefficient remains between 7.10−6 and 9.10−6 cm2 s−1, the nucleation rate constant A and the number density of active sites N0 were growth with the increase of the concentration and the deposition potential. The thin tellurium layers, electrodeposited by chronoamperometry, are characterized by X-ray diffraction. It has been identified that all the films were polycrystalline type hexagonal crystal structure with preferred orientation of (1 0 0) and (1 1 0) planes to growth. The SEM analysis reveals that the morphology of the resulting deposits is depending on the type of electrodeposition mechanism.

The electrolytic deposition of ZrO2 film on ITO glass applied in the detection of rutin

Zirconium dioxide (ZrO2) nanoparticles is deposited on ITO substrates to improve the optical selectivity of ITO glass and applied as a sensor for the detection of rutin. The deposition of ZrO2 nanoparticles was done by the electrochemical method in Zr(NO3)2 aqueous solution at a current density of 11.1 mA/cm2. The mechanism of electrochemical deposition of ZrO2 on ITO glass and the selectivity reaction of rutin with ZrO2 are studied in this work. It demonstrated the compatibility for establishing specific interaction between ZrO2 and rutin and can be used as a suitable surface for pursuing experiments in selective detection of rutin. The developed ZrO2/ITO sensor was applied in the measurement of different rutin concentrations in solution with a good linearity (ranging from 0.3 mM to 1.5 mM). A less sophisticated, cheaper and highly sensitive novel ZrO2/ITO sensor for the detection of rutin has successfully been developed for future applications.

Electrodeposition of Al, Al-Li Alloy, and Li from an Al-Containing Solvate Ionic Liquid under Ambient Conditions

Herein, inspired by previous reports on the electrochemical reduction of Al in diverse electrolyte systems, we describe a novel Al-containing solvate ionic liquid (2:1 (mol/mol) mixture of ethylene carbonate (EC) and AlCl3) that allows low-temperature electrochemical deposition of Al and features the advantages of low cost, ease of preparation, and high electrochemical stability. Electrodeposition of Al-Li alloy and Li can also be realized in this system. Additionally, the above ionic liquid exhibited a saturated vapor pressure of 0.0012 kPa and a conductivity of 1.32 mS/cm at 298 K, which was acceptable for practical applications. To elucidate the electrochemical deposition mechanism, the ionic components of the 2:1 EC/AlCl3 system were characterized by a range of instrumental analysis techniques and theoretical calculations, and Lewis-acidic cations were identified as the electroactive species for Al electrodeposition. Notably, an Al-Li alloy could be obtained by co-deposition in the new solvate ionic liquid, and Li metal could also be electrodeposited on a high-purity Al plate in the form of Al4Li9 and Li3Al2 under ambient conditions using LiCl as a Li source. Al-containing solvate ionic liquids, which to an extent evolved from organic-salts, are of increasing interest. They are expected to gain more attention in the field of electrochemical metallurgy of active metals, due to their higher tunability and lower price.

The Effect of Levelers on Plating through Holes of a PCB By Using Reduced Graphene Oxide (rGO) As a Conducting Layer

Electroless (ELS) copper plating process has been commonly used in the metallization process of printed circuit boards (PCBs), because the sidewalls of the through holes (THs) of PCBs are composited of resin and glass fiber, which are not conductive materials. Hence, before plating these THs, their sidewalls have to be metallized by ELS copper plating. The process causes harmful influence to environment because it contains precious metal (i.e., Pd as a catalyst), formaldehyde and chelating agents. However, reduced graphene oxide (rGO) grafting process, proposed in this work, is environment-friendly and can replace the ELS copper plating process to make the sidewall of the TH of a PCB be conductive for copper electroplating. The rGO grafting process has less steps and an environment-friendly formulation. In this work, the rGO is grafted on the sidewalls of THs of a PCB with a high aspect ratio (AR). We observed that the copper nucleation mechanism of electrochemical deposition on a PCB is progressive. In addition, we studied the suppression of various levelers on copper electrodeposition in order to control the copper to be less deposited at the hole opening but much more deposited at the hole center. Finally, the throwing power (TP) of the copper electrodeposition in the TH can be significantly enhanced. In our research, the effects of electroplating baths, operating parameters and electroplating additives, especially levelers, were investigated for obtaining a high TP of THs. On the other hand, the suppression of various levelers was evaluated by electrochemical analysis, such as linear sweep voltammetry (LSV) and galvanostatic measurements. The results indicate that the electroplating bath containing the leveler with stronger suppression can control the copper to be specifically deposited at the hole opening. Hence, a high TP of plating TH was achieved by using the rGO process. Moreover, the plated TH can pass thermal shock test. That means, a brand-new and promising rGO process can replace the ELS copper plating in the future for producing advanced electronic products.

(Invited) Electrodeposition for Large Scale Photovoltaic Deployment : A Prospective Trial

Photovoltaics is entering a new age. With more than 300 GW of cumulative capacity by the end of 2016, while it was almost zero ten years ago, which represents about 1.5% of the world electricity production, photovoltaics is becoming a key component in the energy transition. The situation is even more evident when considering the contribution of photovoltaics country by country, reaching about 8% in Germany, Italy, Greece. it is also emerging very rapidly in USA, China, India, Chile for instance. It is anticipated that the level of 500 GW will be reached by 2020 and the symbolic one of one TW in the next decade. The reason is that photovoltaics is becoming economically competitive with the traditional energy sector with negociated prices as low as 3 cents per kWh in some regions. However to go futher in this direction will need an disruptive evolution of all the production chain to lower the costs, increase the efficiency and increase the throughput. Up to now the photovoltaic industrial sector is mostly based on wafer based silicon technology and on vaccuum based thin film solar cells of cadmium telluride or copper indium gallium diselenide (CIGS). Electrodeposition is almost absent in this industrial lanscape, excepted for the emerging copper plating technology for the contact in silicon solar cells, and the other experiences for implementing the electrodeposition in thin film technologies failed. Our vision is that in the new context there will be a unique opportunity to demonstrate that electrodeposition can be implemented as a disruptive technology for larger scale PV depoyment. We will recall the results obtained for the electrodeposition of CIGS solar cells from the laboratory to the industrial pilot line in Nexcis ( a spin off of our laboratory). Using a two stage approach from the electrodeposition of metallic precursors followed by thermal selenization, a record cell efficiency of 17.3 % was reached, and modules with full size (120 x60 cm2) at 14% efficiency in 2015, which was equivalent to the state of the art for CIGS modules prepared by vaccuum methods. Unfortunately for economic reasons, as many CIGS companies at that time, the company was stopped in 2015. However the unique features of the CIGS electrodeposition technology for large area and high throughput and robustness was successfully demonstrated. This research line has been maintained in our laboratory and is presently reactivated taking the lessons of the Nexcis experience. We will discuss a new process for the electrodeposition of CIGS absorbers, via an intermediate step consisting in single bath electrodeposition of mixed oxide hydroxyde copper indium gallium layers followed by thermal hydrogen reduction to form the metallic layer before selenization. The deposition of transparent conductive oxide layers by photoelectrodeposition has been successfully developped too and may become a new standard to replace more costly sputtering methods [2-4. We will also present applications and devices which specifically take benefit from a unique advantage electrodeposition approach, that is localized deposition on structured substrates. Two examples will be given: one for the electrodeposition for photovoltaic semitransparent windows and the second one for the deposition of microcells and microlines for a new concept of PV modules working under concentration. In that case we will also discuss of the mechanisms of electrodeposition of multicomponent CIGS films in conditions of microelectrode array configurations, and the challenges for upscaling. We will conclude with some prospective views at longer term as for instance for using electrodeposition in the next generation of PV modules with higher efficiencies (>30%) based on tandem devives, in that case electrodeposition of thin film solar cells could be combined with classical silicon bottom cells. References F. Tsin, et al. Electrodeposition of ZnO window layer for an all-atmospheric fabrication process of chalcogenide solar cell, Scientific Reports 5(2015)8961A. Duchatelet, G. Savidand, N. Loones, E. Chassaing, D. Lincot, Mechanism of Electrochemical Deposition of Cu-In-Ga Mixed Oxide/Hydroxide Thin Films for Cu(In,Ga)Se-2 Solar Cells, J. Electrochem. Soc. 161(2014)D3120 F. Tsin, D. Hariskos, D. Lincot, J. Rousset, Photo-assisted electrodeposition of a ZnO front contact on a p/n junction, Electrochimica Acta 220(2016)176 A. Duchatelet, K. Nguyen, PP Grand, D. Lincot, M. Paire, Self-aligned growth of thin film Cu(In, Ga)Se-2 solar cells on various micropatterns, Applied Physics Letters, 109 (2016) 253901J. Rousset, F. Tsin, M. Guc, J. Vidal, A. Lebris, A. Thomere, V. Izquerdo Roca, D. Lincot, Perchlorate-Induced Doping of Electrodeposited ZnO Films for Optoelectronic Applications J. Physical Chem. C 120(2016)18953 F. Tsin, J. Rousset, A. Lebris, D. Lincot, Electrodeposited zinc grid as low-cost solar cell front contact, Progress in Photovoltaics 24(2016)1123

The roles of temperature and thickness of barrier layer in the electrodeposition efficiency of nickel inside anodic alumina templates

As a dielectric interface, the alumina barrier layer has so far been shown to influence the electrochemical deposition mechanism of different types of ions inside nanopores of anodic alumina templates. Here, the roles of temperature (Tb) and thickness of the barrier layer in the electrodeposition efficiency (EE) of nickel inside 45 nm pore diameter anodic alumina templates, made by the two step anodization process, are reported. By performing a pulsed electrodeposition method, the former role is investigated by increasing Tb from 10 to 50 °C, whereas the latter role is realized by decreasing the final anodization voltage (Vth) from 40 V to 12, 16 and 20 V. While using Tb ~ 20 °C and Vth = 16 V leads to a maximum EE of 65 % in the fabrication of 8.5 μm long nickel nanowires (NWs), the use of Tb ~ 50 °C is indicative of the growth of approximately 3 μm long NWs, resulted from an EE of 20 %. However, by increasing Vth up to 20 V, EE reaches a plateau with an average value of 45 % as a function of Tb. On the other hand, although the crystallinity of the resulting NWs increases by increasing Tb up to 30 °C, the magnetic properties are found to be almost independent of Vth and Tb.

Electrodeposition of Zinc Oxide on Graphene Tips Electrochemically Exfoliated and O2-Plasma Treated

Zinc oxide (ZnO) presents several applications as piezoelectric transducers, photosensors, solar cells, electrochemical sensors, etc. Electrodeposition of zinc oxide (ZnO) thin films from aqueous solution of zinc nitrate has been deposited in graphenated low cost pencil graphite. The electrochemical graphene production at the tips was performed in a low cost DC source using concentrated sulfonitric solution. The tips were expanded in hydrogen plasma and treated by oxygen plasma to enhance its hydrophilicity. The posterior ZnO electrodeposition was highly efficient and the graphene functionalization contributes to overall electrochemical deposition mechanism.

Mechanism of Electrochemical Deposition of Cu-In-Ga Mixed Oxide/Hydroxide Thin Films for Cu(In,Ga)Se2 Solar Cells

Thin films of copper-indium-gallium mixed oxides/hydroxides are electrochemically deposited on molybdenum substrates in aqueous nitrate-based electrolyte in acidic conditions. The process is based on the local pH increase at the cathode surface due to the reduction of nitrate ions. A thermodynamical study shows that the electrochemically induced deposition of copper-indium-gallium mixed oxide/hydroxide films occurs at much higher potentials than their metallic counterparts. A voltammetric study presents the key role of Cu(II) reduction during the process to induce nitrate ions reduction, and shows that the deposition is then controlled by mass transfer of the Cu(II), In(III), Ga(III) species. The composition of the layer is remarkably precisely tuned in a large range of potential, which makes this process highly suitable for the synthesis of Cu(In,Ga)Se2 solar cells.

CdO nanosheet film with a (200)-preferred orientation with sensitivity to liquefied petroleum gas (LPG) at low-temperatures

CdO nanosheet film can be synthesized by electrochemical deposition in an ultra-thin liquid layer by using Cd(NO(3))(2) and HNO(3) as source materials for Cd and oxygen respectively. HNO(3) is also used to adjust the pH of the electrolyte. Studies on the detailed structure indicate that the synthesized CdO nanosheet film has a face-centered cubic structure with (200)-preferred orientation. The response of the CdO nanosheet film to liquefied petroleum gas (LPG) at low temperature has been significantly improved by the novel structure of film. It has exhibited excellent sensitivity and selectivity to LPG at low temperature. A new growth mechanism of electrochemical deposition has been proposed to elaborate the formation of nanosheet in an ultra-thin liquid layer. The self-oscillation of potential in the growth interface and intermediate hydroxide are responsible for the formation of nanosheets.

Nucleation Mechanism of Electrochemical Deposition of Cu on Reduced Graphene Oxide Electrodes

The nucleation mechanism of electrochemical deposition of Cu on reduced graphene oxide (rGO) electrodes has been systematically studied on the basis of the cyclic voltammetry, Tafel plot, and chronoamperometry. Our results show that the experimental parameters including electrolyte concentration, deposition potential, solution pH, and the presence of background electrolyte can determine the nucleation mechanism. Scanning electron microscopy is employed to study the nucleation and growth of Cu on rGO electrodes. This study is significant in development of the electrochemical method in practical applications based on the rGO electrodes.