Morphological insights associated to Instantaneous Nucleation and Growth in Cr(III) Electrodeposition on Nickel in Aqueous Media

The electrochemical deposition of zinc on single-crystaln-type GaN(0001) from a sulphate solution has been investigated on the basis of electrochemical techniques including cyclic voltammetry, chronoamperometry, and Tafel plot. The morphology and crystal structure of zinc deposits have been characterized by means of scanning electron microscopy, X-ray diffraction, and energy-dispersive X-ray analysis. The result has revealed that the deposition of Zn on GaN electrode commenced at a potential of −1.12 V versus Ag/AgCl. According to the Tafel plot, an exchange current density of ~0.132 mA cm−2was calculated. In addition, the current transient measurements have shown that Zn deposition process followed the instantaneous nucleation in 10 mM ZnSO4+ 0.5 M Na2SO4+ 0.5 M H3BO3(pH = 4).

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Polymers designed to control nucleation and growth of inorganic crystals from aqueous media

Macromolecular Symposia ◽

10.1002/1521-3900(200110)175:1<349::aid-masy349>3.0.co;2-9 ◽

2001 ◽

Vol 175 (1) ◽

pp. 349-356 ◽

Cited By ~ 51

Author(s):

Gerhard Wegner ◽

Pia Baum ◽

Maren Müller ◽

Jochen Norwig ◽

Katharina Landfester

Keyword(s):

Aqueous Media ◽

Nucleation And Growth ◽

Inorganic Crystals

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RESPONSE TO ASCORBIC ACID ON POLYPYRROLE FILM MODIFIED BY COPPER PARTICLES

Surface Review and Letters ◽

10.1142/s0218625x18501871 ◽

2019 ◽

Vol 26 (05) ◽

pp. 1850187

Author(s):

I. CHIKOUCHE ◽

C. DEHCHAR ◽

A. SAHARI ◽

N. LOUCIF

Keyword(s):

Ascorbic Acid ◽

Modified Electrode ◽

Three Dimensional ◽

Deposition Process ◽

Nucleation And Growth ◽

Current Time ◽

Force Microscopy ◽

Atomic Force ◽

Instantaneous Nucleation ◽

Polypyrrole Film

In this work, a modified electrode of copper-polypyrrole (Cu-PPy) is elaborated by charging the polymer matrix by Cu particles. The response to ascorbic acid (AA) of this material was tested. The results show good performances. The results indicated a sensitive oxidation peak current of AA on the modified electrode. The success of this application led us to study the nucleation mechanism of copper on the PPy surface which permits to obtain this response. Nucleation and growth of electrodeposited copper onto PPy substrate have been studied in an aqueous solution of 0.01[Formula: see text]M CuCl2 and 1[Formula: see text]M KCl by means of electrochemical methods: cyclic voltammetry, chronoamperometry, and using atomic force microscopy (AFM). The model described by Scharifker and Hills was used to analyze current-time transients. According to this model, the nucleation and growth kinetics at the initial stages of deposition process involve an instantaneous nucleation followed by three-dimensional (3D) growth mechanism.

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Electrochemical study of nickel nucleation mechanisms on glassy carbon at different pH values in an industrial electrolyte

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.1515/ijmr-2020-8046 ◽

2021 ◽

Vol 112 (2) ◽

pp. 143-149

Author(s):

Yangtao Xu ◽

Zhenxu Zhu ◽

Lubin Liu ◽

Zhijian Liu

Keyword(s):

Glassy Carbon ◽

Electrode Surface ◽

Growth Process ◽

Three Dimensional ◽

Spherical Shape ◽

Nucleation And Growth ◽

Nickel Ions ◽

Fine Grained ◽

Instantaneous Nucleation ◽

Nucleation Mechanisms

Abstract The electrochemical behavior of nickel at different pH values in industrial electrolyte was investigated by means of cyclic voltammetry, chronoamperometry and scanning electron microscopy. The results show that the cathodic reaction of nickel ions on glassy carbon electrode surface in industrial electrolyte is a quasi-reversible nucleation and growth process controlled by diffusion. The process is carried out in a three-dimensional instantaneous nucleation and growth mode, and pH values only influence the growth process. The grain size decreased, the deposition rate increased and the density of deposition layer on electrode surface increased with the increase in pH. When the electrolyte pH is 4.8, the grains are uniformly distributed on the electrode surface in a spherical shape with the size of 80 nm, which is the optimum pH value for preparing fine-grained nano-nickel.

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Electrochemical Nucleation and Growth Mechanism of Aluminum on AZ31 Magnesium Alloys

Coatings ◽

10.3390/coatings11010046 ◽

2021 ◽

Vol 11 (1) ◽

pp. 46

Author(s):

Jinling Zhang ◽

Yelei Li ◽

Xiaomin Zhang ◽

Yanchong Yu ◽

Shebin Wang

Keyword(s):

Diffusion Coefficient ◽

Choline Chloride ◽

Three Dimensional ◽

Deep Eutectic Solvent ◽

Nucleation And Growth ◽

Electrochemical Nucleation ◽

Diffusion Controlled ◽

Instantaneous Nucleation ◽

Apparent Diffusion ◽

Al Coating

In this study, the nucleation and growth kinetics behavior of aluminum (Al) were investigated in the Choline-chloride (ChCl)-urea deep eutectic solvent (DES) ionic liquids. The studies of cyclic voltammetric and chronoamperometry demonstrated that the electrodeposition process of Al was controlled by three-dimensional progressive nucleation and instantaneous nucleation. And the growth of nuclei is a diffusion-controlled process. The diffusion coefficient of Al ions was calculated at 343 K, that is, 1.773 × 10−10 cm2/s. The Al coating was obtained on the surface of the AZ31 magnesium alloy electrode under appropriate conditions. According to the surface morphology of the Al film, it could be inferred that the theoretical deposit thickness is similar to the actual thickness, and the apparent diffusion rate of Al ions is slower than the diffusion coefficient in the electrolytes. So, in the later deposition, lamellar Al along the diffusion direction were formed, and lamellar depleted Al zones existed around the big grain Al-rich region.

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AEM analysis of crystallization in Ti-based amorphous alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075142 ◽

1983 ◽

Vol 41 ◽

pp. 270-271

Author(s):

A.R. Pelton ◽

A.F. Marshall ◽

Y.S. Lee

Keyword(s):

Magnetic Properties ◽

Amorphous Alloys ◽

Amorphous Materials ◽

Isothermal Annealing ◽

Amorphous Matrix ◽

Nucleation And Growth ◽

Current Interest ◽

Amorphous Films ◽

Electrical And Magnetic Properties

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.

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Observations oh Nucleation and Growth of Voids in Nickel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069065 ◽

1970 ◽

Vol 28 ◽

pp. 414-415

Author(s):

J. L. Brimhall ◽

H. E. Kissinger ◽

B. Mastel

Keyword(s):

High Purity ◽

Growth Stage ◽

Elevated Temperatures ◽

Early Growth ◽

Nucleation And Growth ◽

Pure Nickel ◽

Different Temperatures ◽

Total Fluence ◽

Neutron Exposure ◽

Growth Of Voids

Some information on the size and density of voids that develop in several high purity metals and alloys during irradiation with neutrons at elevated temperatures has been reported as a function of irradiation parameters. An area of particular interest is the nucleation and early growth stage of voids. It is the purpose of this paper to describe the microstructure in high purity nickel after irradiation to a very low but constant neutron exposure at three different temperatures.Annealed specimens of 99-997% pure nickel in the form of foils 75μ thick were irradiated in a capsule to a total fluence of 2.2 × 1019 n/cm2 (E > 1.0 MeV). The capsule consisted of three temperature zones maintained by heaters and monitored by thermocouples at 350, 400, and 450°C, respectively. The temperature was automatically dropped to 60°C while the reactor was down.

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Electrochemical nucleation and growth of copper on iron and aluminum: A TEM study of industrial copper cementation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109410 ◽

1978 ◽

Vol 36 (1) ◽

pp. 454-455

Author(s):

L.E. Murr ◽

V. Annamalai

Keyword(s):

Metal Surface ◽

Copper Deposit ◽

Nucleation And Growth ◽

16Th Century ◽

Electrochemical Reactions ◽

Mine Shaft ◽

De Re ◽

Copper Precipitation ◽

Electrochemical Nucleation ◽

Interesting System

Georgius Agricola in 1556 in his classical book, “De Re Metallica”, mentioned a strange water drawn from a mine shaft near Schmölnitz in Hungary that eroded iron and turned it into copper. This precipitation (or cementation) of copper on iron was employed as a commercial technique for producing copper at the Rio Tinto Mines in Spain in the 16th Century, and it continues today to account for as much as 15 percent of the copper produced by several U.S. copper companies.In addition to the Cu/Fe system, many other similar heterogeneous, electrochemical reactions can occur where ions from solution are reduced to metal on a more electropositive metal surface. In the case of copper precipitation from solution, aluminum is also an interesting system because of economic, environmental (ecological) and energy considerations. In studies of copper cementation on aluminum as an alternative to the historical Cu/Fe system, it was noticed that the two systems (Cu/Fe and Cu/Al) were kinetically very different, and that this difference was due in large part to differences in the structure of the residual, cement-copper deposit.

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Fundamental Research into Thin Films in a Developing Country

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095753 ◽

1972 ◽

Vol 30 ◽

pp. 500-501

Author(s):

J.A. Eades ◽

E. Grünbaum

Keyword(s):

Thin Films ◽

Growth Process ◽

Empirical Process ◽

Nucleation And Growth ◽

Research Groups ◽

Film Research ◽

Fundamental Research ◽

Controlled Deposition ◽

The One ◽

The University

In the last decade and a half, thin film research, particularly research into problems associated with epitaxy, has developed from a simple empirical process of determining the conditions for epitaxy into a complex analytical and experimental study of the nucleation and growth process on the one hand and a technology of very great importance on the other. During this period the thin films group of the University of Chile has studied the epitaxy of metals on metal and insulating substrates. The development of the group, one of the first research groups in physics to be established in the country, has parallelled the increasing complexity of the field.The elaborate techniques and equipment now needed for research into thin films may be illustrated by considering the plant and facilities of this group as characteristic of a good system for the controlled deposition and study of thin films.

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