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ZnNi-deposits are currently used for corrosion protection especially in the automotive industry. With current REACH1 regulations there is a demand for Ni-free coatings. The objective of this resear...

The paper describes the use of pulse plating on-times outside the usual window in reliable measurement of the surface area of complex parts. Two methods are discussed and analysed; (i) the first ba...

Ni-W electrodes with differing tungsten content as electrocatalysts for the hydrogen evolution reaction (HER) were prepared by pulse plating. The structural and morphological characterisations of t...

Pulse plating of copper has typically found use in the plating of very difficult, high aspect ratio printed circuit boards. Its ability to provide throwing power deep within through holes with aspect ratios as high as 30:1 is well established. This technology has long been thought of as a high technology, high cost, specialty process applicable only to high end products. This paper will discuss the advantages that pulse plating offers over conventional DC copper plating in high volume production applications for panels with aspect ratios of up to 12:1. These advantages are reduced plating time, increased throughput, and reduced plated copper thickness on the panel surface while meeting minimum in-hole copper thickness requirements.

The biennial conference, European Pulse Plating Seminar was held on March 5th and 6th in Vienna for the ninth time. As has become a tradition, the conference was organised as a joint two-day event ...

Nanotwinned copper (nt-Cu) films with ⟨111⟩ crystal orientation were electroplated on Si wafers by pulse plating, with original grain size of ∼1.4 μm. By patterning and annealing the nt-Cu film at ...

A low-cost and durable BiVO4 photoelectrode (PE) is herein synthesized to improve the separation of the electron and hole pair in photoelectrochemical applications. A new synthesis method was envis...

In water based solutions, electrodeposition of Pd and Pd alloys is complicated due to hydrogen embrittlement. This can be avoided by using non-aqueous solutions like deep eutectic solvents ...

The aim of this study is to investigate the impact of WC content on the properties of the Ni–B/WC nanocomposites deposited by the pulse method. It is obtained that, although by addition of WC nanop...

Theoretical aspects of the electrodeposition of composite coatings prepared by pulsed currents and also the variation of coatings hardness with the pulse parameters have been presented in t...

In the current study, electrodeposition-redox replacement was applied to a hydrometallurgical solution with the main elements of Ca (13.8 g L−1), Al (4.7 g L−1), Cu (2.5 g L−1), Zn (1.2 g L−1), Fe (1.2 g L−1), S (1 g L−1), Mg (0.8 g L−1), P (0.5 g L−1) and Ag (3.5 ppm). The solution originated from the leaching experiment of incinerator plant bottom ash, which was dissolved into 2 M HCl media at T = 30 °C. The resulting deposit on the electrode surface was analysed with SEM-EDS and the observed Ag/(Cu + Zn) ratio (0.3) indicated remarkable enrichment of silver on the surface, when compared to the ratio of these elements (Ag/(Cu + Zn)) in the solution (6.8 × 10−5). The enrichment of Ag vs. (Cu + Zn) could be demonstrated to increase ca. 4500 fold compared to the ratio of the elements in solution.

Guidelines are developed in this paper, based on a presentation to the 8th European Pulse Plating Seminar, Vienna, 2018, to facilitate the choosing of appropriate pulse plating parameters for diffe...

Electrodeposition has long been used for the preparation of coatings consisting either of a single metal or a combination of two or more metals in the form of an alloy. At a certain level of techno...

In the present work, the electrodeposition process of Zn-Cr alloy coatings under the conditions of direct and pulse current was discussed. Changes in the Cr content in the obtained alloy coatings, current efficiency of the process, surface morphology, structure and microhardness as a function of chromium(III) concentration in the bath to deposition, current density (direct and pulse) and solution mixing were determined. Surface morphology, structure and hardness of the obtained coatings were investigated. The Zn-Cr alloy coatings of good quality contained up to 0.25 %Cr (for direct current) and up to 9% Cr (for pulse current). The tested Zn-Cr alloy coatings obtained under pulse current conditions showed higher microhardness than the Zn-Cr coatings obtained under direct current conditions and than zinc coatings.

One of the important techniques for developing coatings with proper electrochemical and mechanical properties is electrodeposition method. The goal of the current work is to optimise conten...

In this work, Ni and Ni–Al2O3 nanocomposite coatings were applied on AZ91 magnesium alloy using a pulse plating process and the corrosion resistance of coated samples was evaluated by means of the ...

Ni-W electrodeposits have emerged as one of the most suitable alternatives to hard chromium mainly owing to their remarkable mechanical and tribological properties. Additionally, advanced technologies that require materials resistant to high temperatures could benefit from the use of Ni-W coatings. In this work, the effect of thermal treatment at different temperatures (300, 500, 700°C) on the characteristics of Ni-W coatings obtained by direct and pulse plating (PP) was studied. The morphology, composition, crystalline structure, hardness, wear rate, friction coefficient and corrosion resistance of the thermally treated coatings were analysed and compared with the performance of hard chromium coatings. The results indicate that the pulse-plated Ni-W coatings show better mechanical and tribological properties than the ones obtained by direct current. A significant improvement in hardness in Ni-W layers was achieved by thermal treatment, mainly in the films grown by PP, with minor changes in wear resistance and corrosion performance.

The application of Ibl’s duplex diffusion layer model to the analysis of mass transport in pulse reverse plating with bipolar current pulses has been investigated. Although originally proposed to describe normal pulse plating, Yin has recently extended Ibl’s model to include pulse reverse plating. Using the expressions derived by Yin the pulse limiting current density was determined over a wide range of pulse plating conditions, and then compared to values calculated using more accurate numerical solutions. In general, there was good agreement between the two approaches which demonstrated the essential validity of Yin’s extension to Ibl’s original model. The simplified model is most accurate at long duty cycles, small dimensionless pulse times and for low values of the dimensionless pulse reverse current where its underlying assumptions are most likely to be valid. At very long dimensionless pulse times (i.e. T* > 1) the model becomes increasingly inaccurate and its use in these circumstances cannot be justified.

In current research, electrochemical energy storage systems have gaining interest because they constitute an essential element in the development of sustainable energy technologies. Among them, rechargeable flow batteries (RFBs) are one of the most promising technology for the integration in grid-connected electricity, especially if combined with unpredictable and intermittent renewable energy sources, due to their high efficiency, power/energy independent sizing and room temperature operation. At the moment, among all RFBs systems, the most investigated and advanced technology is the vanadium based RFB, characterized by an energy efficiency equal to 80% and energy density ranging 15-45 Wh/l. However, nowadays the main bulk of research is focused on finding an economically convenient and technically competitive flow battery chemistry, able to ensure long lifetime and high energy efficiency. A zinc-iron RFB with low cost and high energy density will be presented. In particular, inorganic electrolytes based on high soluble salts have been developed, achieving a charge density of 30-70 Wh/l. The electrochemical nucleation and growth of zinc onto a carbon felt current collector in continuous and pulse charging of the battery is studied, showing the achievable improvements in terms of efficiencies and stability of the RFB over charging time. The combination of high energy efficiency of the Zn-Fe RFB with its ability to withstand a large number of charge/discharge cycles and the low cost, makes this battery system suitable for energy storage applications.

Nowadays, Cu_2O is very promising electrode material for photoelectrochemical applications. In this paper, we report on the controllable synthesis of Cu_2O single particles as well as compact layers on Boron Doped Diamond (BDD) electrodes using potentiostatic deposition in continuous and pulse mode. The BDD layers were prepared with different B/C ratios in the gas phase in order to investigate boron doping level influence on the Cu_2O properties. The effect of electrodeposition conditions such as deposition regime and pulse duration was investigated as well. The Cu_2O covered BDD electrodes were analysed by Scanning Electron Microscopy (SEM) and Raman spectroscopy. Improvement in the homogeneity of the electrodeposit and removal of clusters were achieved when the pulse potentiostatic regime was used. Using the same pulse electrodeposition parameters, we confirmed the possibility of controlling the deposition rate of Cu_2O by varying the BDD conductivity. Finally, we were able to scale the size of Cu_2O particles by changing the number of deposition pulses. The obtained results have shown a great potential of controlling the morphology, amount, size and distribution of Cu_2O films on BDD substrates by changing the boron doping level and electrodeposition conditions as well. The investigations reported herein allowed us to better understand the deposition mechanism of Cu_2O on BDD electrodes which could then be used for preparation of active layers for electrochemical applications and in optoelectronic devices such as solar cells and photodetectors.

After the great success of the previous European Pulse Plating Seminars the 7th such conference was held in Vienna, once again, on 3rd and 4th March 2016, marking the 10 year anniversary since the first Pulse Plating Seminar was held in Vienna in 2006. For the second time, the Pulse Plating conference was combined with the annual scientific meeting EAST Forum of the European Academy for Surface Technology (EAST). Owing to this combination, the event could be enlarged to a 2-day conference, providing 26 presentations to the interested audience. The conference and the parallel exhibition focussed on both the scientific and the industrial approach of modern electrochemical surface technology, with a special focus on the pulse plating technique on the second day. Seventy-five participants coming from 16 different countries helped maintain an intensive and very productive discussion on the topic that will be continued in 2018 at the 8th European Pulse Plating Seminar in Vienna. The next EAST Forum will be held...

In order to address lithium dendrite formation and low cycling efficiency issues, Pulse Plating (PP) and Reverse Pulse Plating (RPP) have been systematically investigated for lithium electrodeposition with a modified button cell device. Compared with Direct Current (DC) electrodeposition, PP waveforms with short and widely spaced pulses improve lithium deposition morphology and cycling efficiency under diffusion-controlled conditions. While RPP waveforms with high current density anodic pulses further improve lithium cycling efficiency, no obvious improvement in morphology was seen under the conditions tested. This study suggests that PP and RPP could be powerful tools for utilizing lithium metal anodes in high energy density rechargeable battery systems, especially when high instant power is required.

The electroplating of Ni–W alloys could represent one of the most promising environmentally friendly alternatives to replace hard chromium. However, the Ni–W process and coatings still show some limitations such as lower hardness than hard chromium and limited corrosion resistance that need to be overcome in order to be considered a real solution. In this work, a Ni–W electrolyte was proposed and optimised. A chemometric approach was used in order to design pulse plating experiments and study the effect of experimental parameters on the properties of pulse plated Ni–W coatings. In addition, multivariate analysis was proposed to establish a relation among structural and physical characteristics of Ni–W deposits, and the optimum values of the process parameters required to improve their properties were determined. Results indicate that by the combination of pulse plating and chemometric techniques, Ni–W coatings with improved uniformity, efficiency and hardness compared to those obtained by direct c...

This paper reports on the electrodeposition of Mn–Cu–ZnO for hybrid supercapacitors. This material exhibits a dual structure consisting of Mn-rich highly active, but poorly electronically conducting, grains, which are locked by a Cu-rich highly conductive network that also possesses some degree of charge-storage capacity. This work focuses on morphological, compositional, and chemical-state distributions with submicrometer lateral resolution. This information, which is crucial because doping distribution controls supercapacitor performance, has been obtained by combining electrochemical and in situ Raman measurements with synchrotron-based X-ray fluorescence and absorption microspectroscopy. Using a microfabricated thin-layer three-electrode microcell, we followed the morphochemical changes at different electrodeposition stages and found that pulse-plating allows the growth of Mn- and Cu-doped ZnO as self-organized structures with a consistent spatially stable composition distribution.

This paper describes the effect of modulated bipolar current (pulse reverse plating) on the incorporation of micron and submicron sized SiC particles within an electrodeposited Ni–P alloy matrix (d ...

In the present study, the electrochemical deposition (ECD) of platinum particles on aligned multiwalled carbon nanotube (MWCNT) arrays as novel membrane electrode assembly (MEA) in polymer electrolyte membrane fuel cells was investigated. The ECD was performed using the pulse plating technique and an electrolyte based on potassium tetranitroplatinate(II) salt. The MWCNTs were produced on thin nickel foils by chemical vapour deposition. The MWCNT arrays were electrochemically characterised by cyclic voltammetry in sulphuric acid. The platinum functionalisation of the MWCNT arrays was also investigated by cyclic voltammetry and by scanning electron microscopy. The final preparation of the MEA functionalised MWCNT on Nafion was performed by a hot pressing process.

A research is carried to evaluate the performance between the pulse plating and pulse reverse plating technique. In both the technique employed the composition of the bath is kept constant.Both the plating is done on a double sided Printed Circuit Board for the connection between the two layers. The metal used for plating is silver rather than the conventional copper. The evaluation of parameters such as hardness and current efficiency is carried out.

Fe-Ni-Co ternary alloys are attractive soft magnetic materials, and we have reported a flux gate sensor with an electroplated Fe-Ni-Co film [1]. For improvement in robustness of the sensor output against the temperature variation, an increase in Co content of the film are effective since the Curie temperature increases with increasing the Co content. In the present study, we electroplated Fe-Ni-Co films focusing on the Co content, and evaluated the magnetic and the structural properties.

We have already reported Fe-Pt thick films prepared by an electroplating method [1]. Although we obtained large coercivity in the previous study, reduction in large cracks of the film was a problem to be overcome. In the present study, we focused on increase in the bath concentration in order to reduce large cracks.

The main aim of this work was to investigate the influence of additional parameters in plating process of through-holes technology. Vacuum, ultrasound and the combination of both was used during the activation process of hole's surface. Therefore, research was focused on the activation process, which was revealed as the cause of plating problems. The samples used in this work were prepared with reverse pulse plating.

This paper briefly reviews the preparation of layers of reactive metals and compounds from ionic liquids (ILs) using pulsed electrodeposition. Special focus is given to tantalum electrodeposition from the IL 1-butyl-1-methyl-pyrrolidinium bis(trifluoromethylsulfonyl)amide [BMP][TFSA] onto Ti substrates at room temperature by potentiostatic square pulses. It has been shown that by varying the pulse plating parameters (such as the potential of the on pulse, as well as the frequency and the duty cycle) the morphology of the deposits can be optimised. Thus, experimental conditions have been identified with which uniform and crack free deposits can be obtained.

Experimental investigation of pulse plating parameters on the extent of incorporation of microdiamond abrasives within metallic binder was performed for a micro-abrasive tool. The Taguchi experimental design has been applied to investigate the optimal combination of process parameters to achieve embedment of nominal amount of abrasives in the nickel bond matrix. Analysis of variance (ANOVA) was performed and signal-to-noise (S/N) ratio was determined to know the level of importance of pulse plating parameters. Based on ANOVA, pH of 5.0 (at room temperature) of the pulse plating bath was found to be significant for best abrasive incorporation. These results were experimentally confirmed at 95% confidence level.

Electrodeposited chromium coatings offer high levels of mechanical and tribological properties that justify their use in many industrial and engineering applications. However, one problem of these functional coatings is their limited corrosion resistance and the low current efficiency of their electrodeposition process. Reverse pulse plating can lead to an improvement in the characteristics of chromium deposits, but the high number of variables involved and the interactions among them make the selection of operating parameters difficult. In this paper, a chemometric approach was used in order to design the experiments and study the effect of pulse plating parameters on the properties of chromium coatings. Multivariate analysis was proposed to establish a relationship among structural and physical characteristics of chromium deposits and to determine the pulse parameters required to achieve certain properties. The results indicated that by reverse pulse electrodeposition, it is possible to obtain crack free chromium coatings, with similar hardness values as those obtained from direct current electrodeposited coatings, but with an improved corrosion resistance.

XRD, SEM and photoelectrochemical examinations of deposits formed on the Cu substrate by electrochemical deposition in a water solution containing 0.2 mol dm −3 of ZnSO 4 and 0.002 mol dm −3 of H 2 SeO 3 were performed. Formation of Cu 2 Se x at potentials positive to that of electrochemical deposition of ZnSe was proved by the XRD technique. The formation of Cu 2 Se x continued even after deposition due to further diffusion of the deposited Se into Cu. A nano-crystalline ZnSe of cubic structure was electrodeposited at a potential of −0.62 V vs. Ag/AgCl electrode and XRD examination of deposits formed using cyclic potential scanning and pulse plating revealed the presence of hexagonal ZnSe along with the cubic one. A photoelectrochemical characterization proved that the electrodeposited ZnSe was a p-type semiconductor. A significant amount of Cu 2 Se x was formed during annealing of ZnSe electrodeposited on the Cu substrate although only traces of copper selenide were detected before the annealing. ZnSe, SnSe and a small quantity of Cu 2 Se x were detected by XRD after annealing of ZnSe electrodeposited on the Cu–Sn/Mo/glass substrate.

Pulse plating (PP) has been gaining in importance, according to a report of the third European Pulse Plating Conference in Austria, by Hansal.1 A number of diverse potential applications, apart fro...

Thin nickel sheets were fabricated by electroforming, and cold rolled to improve their strength. The thin nickel sheets have very fine grains with a {001}huv0i fiber texture. Cold rolling results in evolving a {001}h110i orientation and the formation of a weak {111}huvwi fiber component. Micro-hardness of the nickel sheet on the surface normal to the normal direction (ND) was increased from 247.8 to 354.4Hv by cold rolling with 87.5% reduction. The corrosion potential and corrosion rate of the nickel sheet in artificial sea water were in the ranges of 127 to 112mVSCE and 4.2 © 1017­1.8 © 1016A cm12, respectively. The change in corrosion behavior with cold rolling on the surface normal to ND has little relation to crystallographic texture because of a stable {001} texture during rolling, unlike nickel bulk samples. [doi:10.2320/matertrans.MA201224]

Cadmium is a bluish white metal with the atomic number 48 and it is found in group 12 of the periodic table, along with zinc and mercury. It was jointly discovered by two German scientists in 1817 ...

Monolithic and multilayered iron electrodeposits were successfully synthesized by the pulse plating electrodeposition method. Electron microscopy and Vickers microhardness measurements were used to investigate the microstructure and mechanical properties of the iron electrodeposits produced. Two types of monolithic iron coatings were produced, one with a coarse grained, columnar structure and the other with an ultra-fine grained structure. Hall-Petch type grain size strengthening was observed in these monolithic coatings. Multilayered iron coatings composed of alternating layers of coarse grained and fine grained structures were also produced. The hardness value of the multilayered coatings falls between the hardness values for the two types of monolithic coatings produced. This study has demonstrated the possibility of applying a multilayered structure design to tailor the microstructure and mechanical properties of electrodeposited iron coatings.

Pulse plating of Sn-Bi alloys were investigated from a bath containing three compounds, including citric acid (CA), ethylenediaminetetraacetic acid (EDTA), and polyethylene glycol (PEG400) at pH = 1. Based on the linear sweep voltammetric (LSV) analysis, the large gap in the onset deposition potential between Sn and Bi metals led to displacement deposition at the interface between metallic Sn atoms and Bi3+ ions in the time-off (toff) period. Consequently, the pulse-plating parameters (i.e., duty percentage in the pulse cycle and pulse frequency) were adjusted to affect the double-layer charging effect and the mass transport process to control the composition and morphology of alloys. This pulse plating method provides a reliable route to obtain uniform Sn-Bi alloys of high Sn contents (e.g., 80Sn-20Bi and 90Sn-10Bi) and the eutectic 42Sn-58Bi deposit. Various Sn-Bi deposits were characterized by the scanning electron microscopic (SEM), energy-dispersive spectroscopic (EDS), and X-ray diffraction (XRD) analyses.

This paper reviews and discusses briefly some fundamentals of the electrocrystallisation of silver from cyanide electrolyte that may be significant for the development and application of pulse plating and power modulation in electroplating, especially for the electronics industries. Within the Helmholz double layer slow processes are distinguished from fast. It is concluded that a better knowledge and understanding of the slow stages of electrocrystallisation may come from modern optical studies. It is necessary to relate the phenomenology of electrocrystallisation to the material properties of an electrodeposit, especially to its electrical and thermal conductivities.

In this study, the influence of pulse plating on the microstructure, morphology and corrosion properties of semibright nickel layers was investigated and it was observed that applied pulse sequences led to deposits with higher corrosion resistance than those obtained by direct current. Moreover, the study of the effect of pulse plated semibright nickel deposits on double layer nickel coatings showed that the applied pulse sequences provoked an increase in potential difference between individual nickel layers, favouring the lateral spread of pitting corrosion and reducing its penetration to substrate. In addition, the influence of the applied pulse sequences on the consumption of the organic additives in the semibright nickel electrolyte was evaluated, observing that this influence was similar to that given by direct current.

This paper describes how copper plating is influenced by modulated current. By unipolar pulse plating smooth, compact and fine grained structures can be obtained, but the macro throwing power is worse than by direct current plating. The best throwing power is obtained by pulse reverse plating. In additive containing solutions, excellent throwing power has been obtained at the following parameters: T c/T a=20, i a/i c=1–3·5 and Q a/Q c

In this paper, the influences of pulse plating parameters and additives upon the uniformity of through-hole copper plating were investigated by orthogonal experimental design methods. Firstly, the L9 (34) level experiments were employed to study the effects of PEG-8000, SPS, Cl– and JGB, on the uniformity of through-hole copper plating. It was found that SPS was the key factor for the uniformity, and PEG followed; 86·7% uniformity was obtained with appropriate additive concentrations. In addition, the interactions between the major influential factors, namely SPS and PEG-8000 were studied under fixed Cl– and JGB concentration, and 88·7% uniformity was observed. The L25 (56) experiments were employed to study the impacts of pulse parameters on the uniformity of through-hole copper plating under the confirmed additives concentration. The results indicated that the forward pulse current (J avg.c) made the greatest contribution in the uniformity of through-hole copper plating, followed by the forward...

CoFe alloys with 50–70% Fe have the highest magnetic moment of 2.4 T. There have been numerous research and development studies dedicated to achieving 2.4 T soft magnetic films by electrodepositing CoFe and CoFeNi alloys. The high tensile stress of the electrodeposited high moment films is one of the key causes slowing down the implementation of CoFe alloys. There have been few reported studies on the structure and stress evolution during the deposition of CoFe film either by vacuum processes or solution processes. This work reports on the preliminary finding related to the tensile stress in electrodeposited CoFe films as a function of grain size, alloy composition, and other deposition parameters. The residual tensile stress was found to increase with decreasing grain size in the film, which was accompanied by the increase of iron content in the films. Pulse plating study demonstrated to have little effect on film stress. Solution temperature was found to be highly effective in reducing tensile stress in the film, which is speculated to be attributed to the increased grain size from elevated deposition temperatures.

The benefi ts of anode shielding, either physically by an inert grid placed above the anode or by a grid electrically connected to the anode, are reviewed. During operation in practice and in laboratory investigations with a range of plating solutions, shielding has been found to reduce additive consumption and hence the need for bath regeneration, to reduce the effect on the active layer in pulse plating reverse mode, to reduce oxidation of cations, and to increase stability of performance over the life of the anode.