Electrodeposition of iron-molybdenum alloy from ammonia-citrate electrolyte

Fe-Mo deposits were obtained from ammonia-citrate electrolyte at the potentials to the negative of -0.8 V (NHE). The method of X-ray photoelectron spectroscopy was used to establish that iron and molybdenum are included in the metallic form into the coating formed on the cathode. In the range of potentials of ?0.90 to ?1.10 V, the ratio between partial current densities of iron and molybdenum electrodeposition remains practically constant, which is the cause of independence of the chemical composition of the alloy on the current density in a wide range of potentials.     

Electrocatalytic properties of cobalt-molybdenum alloy deposits in the hydrogen evolution reaction

Electrocatalytic activity of cobalt-molybdenum deposits is studied in the hydrogen evolution reaction (HER) in an alkaline solution. The studied electrode materials were obtained electrochemically in the galvanostatic mode. It is shown that the rate of hydrogen evolution in 1 M NaOH at 293 K at the Co-Mo alloy is higher, as compared to pure cobalt deposits obtained in similar conditions, which is due both to the increase of the electrode true surface area and possibly to the electronic structure of the obtained alloys. It is established that the hydrogen reaction exchange current grows at the increase of molybdenum content in the electrode deposits in the range of 0–40 at %.     

Chronoamperometric studies in an ammonia citrate electrolyte for the deposition of a nickel-molybdenum alloy

Dependences of the current and the chemical composition of cathodic deposits on the electrolysis time are studied in an ammonia-citrate electrolyte for the deposition of a nickel-molybdenum alloy in potentiostatic conditions. At potentials less negative than ?0.93 V, no nickel-molybdenum alloy deposition occurs and in the course of electrolysis there is observed a decrease in the current, which is connected with the blocking of the electrode surface by the formed molybdenum oxides. In the region of potentials of deposition of a nickel-molybdenum alloy there is realized the following shape of a time dependence of the current. Within the first few seconds of the electrolysis process, the current somewhat decreases. Then there occurs its increase, which is connected with the alloy deposition on the cathode. In the course of electrolysis there occurs a decrease in the molybdenum content in the cathodic deposit.     

Electrodeposition of a lead-indium alloy from an acetic electrolyte

Electrodeposition of a lead-indium alloy from an acetic electrolyte containing a “Drop VOX superactive oxygen” cleanser (technical specification 2383-063-14551353-05) as a surfactant was studied.     

Electrodeposition of tin-cobalt alloy from a sulfate electrolyte with organic additives

Electrodeposition of a tin-cobalt alloy from a sulfate electrolyte with organic additives was studied.     

Electrodeposition of silver-indium alloy from cyanide-hydroxide electrolytes

It is shown that periodical spatio-temporal structures, consisting of phases with different indium content, are observed on the electrode surface during silver-indium alloy deposition from cyanide electrolytes in galvanostatic mode. The effect of electrolysis conditions on the silver-indium alloy appearance and morphology is studied, using optical and scanning electron microscopy; the phase composition of the obtained heterogeneous coatings, overall deposition rate, coating roughness, and microhardness are determined.     

Electrodeposition of tin-indium alloy from a sulfate electrolyte in the presence of organic substances

Electrodeposition of the Sn-In alloy from a sulfate electrolyte in the presence of synthanol, formalin, and butynediol-1,4 was studied. An electrolyte composition and conditions for obtaining an alloy of prescribed composition are suggested.     

Electrodeposition and characterization Zn-Co alloy

The present work details optimization of a stable acid chloride bath for electroplating of bright Zn-Co alloy on mild steel using gelatin and glycine as additives. It was found that the addition of gelatin along with glycine changed the deposition pattern markedly. A suitable bath has been formulated using conventional Hull cell experiments. The bath under plating conditions were found to exhibit anomalous codeposition with preferential deposition of less noble (zinc) over more noble (cobalt) as characterized by Zn-Fe group metal alloys. Investigation revealed that the current density (c.d.), temperature, and pH of the bath have strong effect on the composition of the deposit. Influence of bath constituents and operating parameters on appearance and composition of deposits were studied as measure of their performance against corrosion. A variety of deposits were obtained and their corrosion resistances were measured by Tafel method with/without chrome passivation. Experimental results demonstrated the fact that the corrosion resistances of Zn-Co alloys increased with percent of Co in the deposit except at very high c.d. This is due to the fact at very high c.d. the deposit becomes very porous and thick as evidenced by SEM image. The formation of Zn-Co alloy is confirmed by EDAX analysis. A stable chloride bath for Zn-Co alloy deposition has been proposed and discussed. The formation of passive film on chromatization is indicated by almost same E _corr value of all Zn-Co electroplates irrespective of the current densities at which they have been deposited. Published in Russian in Elektrokhimiya, 2009, Vol. 45, No. 7, pp. 811–816. The text is published in the original.     

Electrodeposition of chromium-molybdenum alloy from electrolyte based on chromium(III) sulfate

The conditions of chromium-molybdenum plating from the electrolytes based on chromium(III) compounds are studied. It is shown that the deposits containing to 2 wt % molybdenum can be obtained by introducing sodium molybdate into the composition of electrolytes based on chromium(III) compounds. The introduction of molybdenum into the composition of chromium electrodeposits enhances their corrosion resistance in the media containing chloride ions.     

Electrodeposition of Mo-Se thin films from a sulfamatic electrolyte

Mo-Se thin films have been electrodeposited on conducting tin oxide (SnO₂) coated glass substrates from a sulfamatic solution containing Na₂MoO₄ and H₂SeO₃ under potentiostatic conditions. The deposition potential varied from –0.6 V to –0.9 V, at a deposition temperature of 20–40 °C and pH 6.5. X-ray diffraction analysis revealed that the overall composition of the films deposited is consistent with the formation of MoO₂ and MoSe₂. The lattice parameters of the as-deposited MoSe₂ are a=b=3.2340 Å and c=13.2859 Å, which fits a hexagonal structure.     

Electrodeposition of nickel-based composite coatings from a sulfamate electrolyte

Russian Journal of Applied Chemistry - Nickel-based composite coatings modified with carbon nanotubes were electrodeposited from a sulfamate electrolyte. The functional properties (friction...     

Electrodeposition of bismuth from acid lactate electrolyte

Electrodeposition of bismuth from acid lactate electrolyte was studied.     

Electrodeposition of iron-molybdenum coatings from citrate electrolyte

Specific features of the electrodeposition of iron-molybdenum coatings from a citrate electrolyte based on iron(III) sulfate and sodium molybdate in dc and unipolar pulsed modes were studied. It was demonstrated that bright compact coatings with varied content of molybdenum can be produced by varying the relative concentrations of salts of the alloy-forming components and the solution pH. The current density ranges providing the high efficiency of the galvanostastic electrolysis were determined and it was shown that using the pulsed mode makes smaller the amount of nonmetallic impurities in a coating, diminishes its roughness and leads to formation of surface layers with a more uniform composition, The iron-molybdenum coatings exhibit a high corrosion resistance in corrosive media and physicomechanical properties improved as compared with the base metal, which makes it possible to recommend these coatings for protection from corrosive-mechanical disintegration and restoration of the surface of worn articles.     

Electrodeposition of nanocrystalline Ni–Cu alloy from environmentally friendly lactate bath

A new environmentally friendly electroplating bath for Ni–Cu alloy deposition was developed. Lactic acid was used as a complexing agent. The influence of bath composition, current density, pH and temperature on cathodic polarization, cathodic current efficiency and alloy composition was studied. Different proportions of the two metals were obtained by using different deposition parameters, but at all [Ni²⁺] / [Cu²⁺] ratios studied, preferential deposition of Cu occurred and regular co‐deposition took place. The Ni content of the deposit increased with Ni²⁺ content and current density and decreased with temperature. The surface morphology of the deposited Ni–Cu alloy was investigated using scanning electron microscopy. The crystal structure was examined using the X‐ray diffraction technique. The results showed that the deposits consisted of a single solid solution phase with a face‐centered cubic structure. The crystallite size lies in the range of 12 to 25 nm for as‐plated alloys. Copyright © 2014 John Wiley & Sons, Ltd.     

Electrodeposition mechanism of Ni-Mo-P alloy in the solution of ammoniac citrate

The induced codeposition mechanism of Mo, P and Ni from the solution of ammoniac citrate was studied by means of steady-state polarization, AC impedance and X-ray Photoelectron Spectroscopy (XPS). The result of electrochemical measurements proved that [NiCit(NH3)2]- is the electro-active species of nickel, though nickel ions exist mainly as [NiCit(NH3)3]- in ammoniac citrate. XPS experiments proved the existence of tetravalent molybdenum corresponding to MoO2 on the surface of some deposits. The intermediate product, MoO2, was probably reduced to Mo in the alloy deposit by atomic hydrogen adsorbed on the induced metal nickel. The reduction of H2PO2- occurs through two distinctive steps with PH3 as an intermediate, which subsequently reacts with atomic hydrogen to form P in the alloy deposit. The electrodeposition mechanism was proposed in this paper.     

Electrodeposition of lustrous zinc coatings from sulfate electrolyte

The electrodeposition of lustrous zinc coatings from a sulfate electrolyte containing ZnSO₄, Na₂SO₄, buffer additives, and 2-butyne-1,4 diol was studied.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 8, 2004, pp. 1284–1288.Original Russian Text Copyright © 2004 by Medvedev, Makrushin.     

Electrodeposition of hard iron-zirconia dioxide composite coatings from a methanesulfonate electrolyte

A study of electrodeposition of iron-based composite coatings containing zirconia dioxide particles from sulfate and methanesulfonate electrolytes showed that the zirconia dioxide content in the deposits obtained from the latter electrolyte can reach 10–12 wt %. Models of the process of ZrO₂ particle incorporation into an iron matrix were considered. The microhardness of the composite deposits was estimated.     

Electrodeposition of cadmium from a sulfate electrolyte in the presence of a fixative

Electrodeposition of cadmium from a sulfate electrolyte containing CdSO₄ · 8/3H2O, H₂SO₄, and a fixative was studied.     

水溶液中Ni-La-P合金的电沉积行为

为了开发含稀土的功能材料,我们研究了从水溶液中电沉积Ni-La-P合金工艺[1].刘淑兰等[2]报道了电沉积的Ni-La合金上的阴极析氢行为,但未见Ni-La合金电沉积行为的报道.本文采用动电位扫描法,研究了电沉积Ni-La-P合金过程中,镀液中的配体、H3PO3和Ni2 离子的作用.采用动电位扫描法测量合金电沉积时的阴极极化曲线.所用仪器有DHW型恒电位仪（延边电化学仪器厂）,YEW-TYPE-3086型X-Y函数记录仪（四川仪表四厂）.电极：阴极为1cm2铜片,阳极为5cm2Pt片,参比电极：饱和甘汞电极（SCE）.实验溶液广：NiCl2·6H2O25g/L,NH4Cl9g/L,L1-…     

Ni-W alloy coatings deposited from a citrate electrolyte

Ni-W alloy coatings were deposited by applying current pulses with different pulse parameters at 60°C onto mild steel substrates from aqueous electrolytes with different tungstate concentration. Morphology and composition of the alloys were analyzed by SEM and EDX, respectively. XRD was used to determine metallic phases. Scanning electron micrographs revealed that deposition parameters had a strong effect on the morphology of the coatings. Increasing the duty cycle or decreasing the off time led to a compact morphology. Corrosion properties of the coatings were investigated by potentiodynamic polarization in a chloride medium. It was found that compact morphology of the deposits and high content of tungsten in the coating contribute to satisfactory corrosion results of Ni-W alloy coatings under the conditions studied.