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1

Electrochemical Reactions to Form Composite Layers Aluminium Oxide-Metal

100%

Tomassi P.

Acta Physica Polonica A

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2002

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vol. 102

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issue 2

215-220

EN

Processes leading to the formation of the composite layers aluminium oxide-metal have been investigated. Structure, composition, and other properties of this material have been examined. The mechanism of metal electrodeposition process is discussed.

2

Effect of the Applied Current Density on the Structural and Magnetic Properties of the Electrodeposited Cobalt-Nickel Alloy Thin Films

80%

Özdemır R.

Acta Physica Polonica A

|

2017

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vol. 132

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issue 3

770-774

EN

In this study, cobalt-nickel (Co-Ni) alloys were deposited electrochemically onto aluminum substrates under applied current densities of 103.8, 138.4, 173 and 207.6 A m¯². Influence of the applied current density on the structural and magnetic properties of the Co-Ni alloys was investigated. The bath for Co-Ni alloys deposition was composed of 0.08 mol l¯¹ CoSO₄·7H₂O, 0.2 mol l¯¹ NiCl₂·6H₂O, 0.1 mol l¯¹ NiSO₄·6H₂O and 0.25 mol l¯¹ H₃BO₃. The electrochemical investigation of Co-Ni alloys was completed using cyclic voltammetry and galvanostatic studies. Inductively coupled plasma analysis has shown that the amount of the cobalt in the deposited alloy has decreased from 73.61% to 67.01% with the increase of the applied current density from 103.8 to 207.6 A m¯². According to the magnetic analysis results, the values of coercivity coefficient of the deposited Co-Ni alloys range between 115 and 150 Oe, confirming ferromagnetic behavior of the alloys. Experiment results indicate that magnetic and structural properties of the Co-Ni alloy deposits are greatly influenced by the applied current density in the electrodeposition system.

3

Electrolytic Plasma Surface Cleaning of Industrial Metallic Components

80%

Kumruoglu L., Özel A.

Acta Physica Polonica A

|

2014

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vol. 125

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issue 2

379-381

EN

Electrolytic plasma is an emerging, environmentally friendly surface engineering technology that can be used for cleaning of metal surfaces and removing several coating. The present work was concerned with cleaning of corrosion products (oxides and contamination) on steel surfaces for corrosion protection. The effects of processing parameters on cleaning steel surfaces were investigated. The results show that electrolytic plasma can effectively produce clean surfaces and remove iron oxides. Also the arc spray coatings deposited on steel was removed by electrolytic plasma.

4

Growth of Pt-Ni Nanoparticles of Different Composition using Electrodeposition and Characterization of Their Magnetic Properties

80%

Kožejová M., Hložná D., Hua Liu Y., Ráczová K., Čižmár E., Orendáč M., Komanický V.

Acta Physica Polonica A

|

2017

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vol. 131

|

issue 4

839-841

EN

We prepared Pt₃Ni and PtNi₃ nanoparticles of various sizes on conductive and atomically smooth highly oriented pyrolytic graphite surfaces using potentiostatic electrodeposition. We can control the size of electrodeposited nanoparticles and their density on the surface by changing the deposition time. The morphology of nanoparticles was determined by scanning electron microscopy. PtNi₃ particles have spherical shape, while Pt₃Ni particles have more irregular shape. Composition of particles was confirmed by energy dispersive spectroscopy. We have measured magnetic properties of both systems with 100 s preparation time, superparamagnetic behavior was observed in PtNi₃ nanoparticles with blocking temperature T_{B}=225 K.

5

Structure and Corrosion Resistance of Nickel-Molybdenum Alloy Coatings

80%

Popczyk M., Zacharz M., Osak P., Dercz G., Łosiewicz B.

Acta Physica Polonica A

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2016

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vol. 130

|

issue 4

1072-1074

EN

Electrolytic Ni-Mo alloy coatings were obtained from the galvanic bath, at the temperature of T= 60°C under galvanostatic conditions using a cathodic current density of j= 80 mA cm¯². Surface morphology was studied using a scanning electron microscopy. Chemical composition of obtained coatings was determined by the energy dispersive spectroscopy. Structural studies were carried out using an X-ray diffraction method. Electrochemical corrosion resistance tests were carried out in 5% NaCl solution. It was found that X-ray diffraction investigations of all obtained coatings showed the characteristic "halo", which suggests that the obtained deposits have an amorphous structure. Chemical composition and corrosion resistance of the electrolytic Ni-Mo coatings depend on the concentration of Na₂MoO₄· 2H₂O in a galvanic bath. With the increase of the molybdenum content in the alloy coatings, their corrosion resistance increases.

6

Investigation of the Structural and Magnetic Properties of the Cobalt-Nickel Alloys Fabricated in Various Electrolyte Solutions

80%

Özdemır R., Korkmaz C., Karahan İ.

Acta Physica Polonica A

|

2017

|

vol. 132

|

issue 3

1045-1049

EN

Cobalt-Nickel alloys have been widely used for decoration, in magnetic recording devices and corrosion resistance applications, etc. In this study, the influences of cobalt amount in electrolyte on the magnetic and structural properties of the electrodeposited Co-Ni alloys were investigated. An electrolyte solution, consisting of cobalt sulfate, nickel sulfate, nickel chloride and boric acid, was used in electrodeposition. The electrochemical investigation of Co-Ni alloys was completed using cyclic voltammetry and galvanostatic studies. The morphological and structural analyses of the alloys were performed using inductively coupled plasma, scanning electron microscopy, X-ray diffraction and vibrating sample magnetometer techniques. The effect of cobalt concentration on the magnetic properties, phase structure and grain size of the alloys was investigated. Magnetic hysteresis results indicate that the amount of the cobalt content in the electrolyte has a strong influence on the ferromagnetic behavior of fabricated alloys. Results of the study show that changing the electrodeposition parameters, such as composition of electrolyte solution, allows to fabricate alloys with different properties.

7

Hydrogen Sensors Made on InP or GaN with Electrophoretically Deposited Pd or Pt Nanoparticles

70%

Zdansky K., Cernohorsky O., Yatskiv R.

Acta Physica Polonica A

|

2012

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vol. 122

|

issue 3

572-575

EN

High quality Schottky diodes were prepared by printing colloidal graphite on the polished wafers of n-type InP or n-type GaN. The wafers were earlier sparsely covered with palladium or platinum nanoparticles by electrophoresis from prepared colloid solutions in isooctane. Deposited contacts and nanoparticles were observed by scanning electron mictroscopy. Current voltage characteristics of the Schottky diodes showed high rectification ratios and the barrier heights close to the value of vacuum-level-alignment of the Schottky-Mott limit. The sensitivity to hydrogen of the diodes was measured in the flow of hydrogen/nitrogen mixtures of various hydrogen concentrations in the range from 1 ppm to 1000 ppm. The estimated detection limits of the diodes were in the sub-ppm range. The diodes represent orders-of-magnitude improvement over the best hydrogen sensors reported previously.

8

Investigation of Nanocrystalline Materials by Perturbed Angular Correlation and Supplementing Experimental Techniques

70%

Wolf H.

Acta Physica Polonica A

|

2006

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vol. 109

|

issue 3

433-440

EN

Nanocrystalline materials were investigated by perturbedγγ-angular correlation using the radioactive probe ^{111}In. For identifying local structures observed by perturbedγγ-angular correlation various supplementing experimental techniques, like X-ray diffraction, transmission electron microscopy, absorption spectroscopy, and photoluminescence spectroscopy, were applied. In nanocrystalline TiAl alloys different crystallographic structures were observed depending on the conditions of sample treatment. Nanocrystalline Ni samples show a slightly modified local magnetic field in regions adjacent to the grain boundaries. In addition, ordered grain boundary structures were observed. Ni precipitates were identified in nanocrystalline NiCu alloys by perturbed γγ-angular correlation and preparation conditions avoiding these precipitates were found. For nanocrystalline ZnO preparation conditions were found yielding In-doped particles of good crystalline quality.

9

Electrochemical Deposition of Nanowires in Porous Alumina

70%

Kalska-Szostko B., Brancewicz E., Mazalski P., Sveklo J., Olszewski W., Szymański K., Sidor A.

Acta Physica Polonica A

|

2009

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vol. 115

|

issue 2

542-544

EN

Electrochemical deposition is a very efficient method for producing many types of modern materials. The method is not expensive and does not have a limit for sample size. In our work the preparation of Ni, Co and Fe nanowires is presented. The obtained nanowires had different diameter and length which were tunable by template porous material and time of deposition, respectively. The quality of the prepared wires was dependent also on deposition mode. The smallest wires of the diameter around 40 nm were prepared in porous anodic alumina oxide obtained from oxalic acid. The largest ones, around 120 nm, were produced in phosphoric acid. The length could be as large as the thickness of the oxide and reached up to about 1 μm. The morphology of wires was studied by atomic force microscopy and scanning electron microscopy. The magnetic characterization was done with usage of magnetic force microscopy and the Mössbauer spectroscopy. The wires show magnetization along their growth direction.

10

Influence of Cu Layer Thickness on Morphology and Magnetic Properties of Co/Cu Nanowires

61%

Kac M., Kopec M., Cieniek L., Zarzycki A., Kac S., Maximenko A., Dutkiewicz E., Marszalek M.

Acta Physica Polonica A

|

2018

|

vol. 133

|

issue 2

302-305

EN

We studied changes of morphology and magnetic properties of Co/Cu multilayered nanowires, electrodeposited in polycarbonate membranes, as a function of Cu layer thickness. The morphology and structure of wire assemblies with an average diameter of 200 nm and length of 10 μ m, investigated by X-ray diffraction and scanning electron microscopy techniques, revealed polycrystalline structure of Cu and Co layers with smooth lateral surface of nanowires. Overdeposited nanowires created caps which showed flower-like dendrites with shape changing as a function of Cu thickness and electrodeposition parameters. Chemical composition of Co and Cu nanowires analysed by energy dispersive spectroscopy and proton induced X-ray emission showed Cu nanowires free from Co atoms while in Co nanowires, Cu contamination with concentration below 10% was observed. The oxidation traces observed in single-component Cu nanowires did not appear in multilayered nanowires. Magnetic measurements indicated easy axis of magnetization in membrane plane for nanowires with Cu thickness smaller than 20 nm, whereas for larger Cu thicknesses isotropic orientation of magnetization was observed. The presence of Cu atoms in single-component Co nanowires resulted in the appearance of magnetic anisotropy with easy axis along nanowire axis and the increase of coercivity value.

Refine search results

Electrochemical Reactions to Form Composite Layers Aluminium Oxide-Metal

Effect of the Applied Current Density on the Structural and Magnetic Properties of the Electrodeposited Cobalt-Nickel Alloy Thin Films

Electrolytic Plasma Surface Cleaning of Industrial Metallic Components

Growth of Pt-Ni Nanoparticles of Different Composition using Electrodeposition and Characterization of Their Magnetic Properties

Structure and Corrosion Resistance of Nickel-Molybdenum Alloy Coatings

Investigation of the Structural and Magnetic Properties of the Cobalt-Nickel Alloys Fabricated in Various Electrolyte Solutions

Hydrogen Sensors Made on InP or GaN with Electrophoretically Deposited Pd or Pt Nanoparticles

Investigation of Nanocrystalline Materials by Perturbed Angular Correlation and Supplementing Experimental Techniques

Electrochemical Deposition of Nanowires in Porous Alumina

Influence of Cu Layer Thickness on Morphology and Magnetic Properties of Co/Cu Nanowires