Electrocrystallization nucleation

W. J. Lorenz, E. Schmidt, G. Staikopv and H. Bort, 12th Faraday Symposium. Electrocrystallization, Nucleation and Phase Formation, Southampton, England (1977). 

Milchev A (2008) Electrocrystallization nucleation and growth of nano-clusters on solid surfaces. Russ J Electrochem 44 619-645... 

Budevski, E., Staikov, G. and Lorenz, W.J. (2000) Electrocrystallization nucleation and growth phenomena. Electrochimica Acta, 45, 2559. 

By electrodeposition of CuInSe2 thin films on glassy carbon disk substrates in acidic (pH 2) baths of cupric ions and sodium citrate, under potentiostatic conditions [176], it was established that the formation of tetragonal chalcopyrite CIS is entirely prevalent in the deposition potential interval -0.7 to -0.9 V vs. SCE. Through analysis of potentiostatic current transients, it was concluded that electrocrystallization of the compound proceeds according to a 3D progressive nucleation-growth model with diffusion control. 

Obretenov W, Bostanov V, Popov V (1982) Stochastic character of two-dimensional nucleation in the case of electrocrystallization of silver. J Electroanal Chem 132 273-276... 

Sometimes, semiconductivity depends on the type of a structural phase that arises from synthesis. Thus, in the case of (TCNQ) Cu the semiconducting phase is thermodynamically disfavored. To prepare this semiconductor, Harris et al. (2005) proposed to perform the reduction of TCNQ in acetonitrile at glass-carbon, gold, or platinum electrode in the presence of Cu. This allows the electrocrystallization of sparingly soluble TCNQCu semiconducting phase to occur by a nucleation... 

The same mechanism of zinc electrodeposition on the GC electrode was observed in sulfate, chloride, and acetate ion solutions [227]. The anions mainly affected the nucleation densities during zinc deposition, which resulted in a different surface morphology. The nucleation rate constant was the same in the chloride and sulfate solutions and was equal to 1.22 x 10 s h In the presence of acetate and chloride ions, the deposited zinc film tends to grow in a multilayered pattern, while in sulfate solution, the zinc deposition forms irregular grains. A new approach to the estimation of zinc electrocrystallization parameters on the GC electrode from acetate solutions was described by Yu et al. [228]. 

The experimental data for the rate of stationary two-dimensional nucleation in electrocrystallization of cadmium on the surface of the Cd(OOOl) crystal face in 2.5 M CdS04 aqueous solution at 45 °C were presented [234]. The overpotential dependence of the nucleus size was determined. 

We now consider briefly how nucleus formation on an electrode surface, electrocrystallization, can be studied. Nucleation normally follows a first-order rate law... 

He started to work at the Chemical Faculty of Sofia University where he became a professor and the head of the Department of Physical Chemistry, in 1947. Kaishev founded the Institute of Physical Chemistry of the Bulgarian Academy of Sciences in 1958, and helped to establish the Central Laboratory of Electrochemical Power Sources [i]. Kaishev started to collaborate with - Stran-ski in Berlin in 1931 [iii] and became his assistant in Sofia in 1933. They laid the fundamentals of the crystal growth theory. They proposed the first kinetic theory of the two-dimensional nucleation and growth. The spiral type growth during electrocrystallization was first observed by Kaishev on silver [iii]. On the history of the creation of the molecular-kinetic theory of crystal growth see [iv]. 

Refs. [i] MilchevA (1985) Electrochim Acta 30 125 [ii] MilchevA (1986) Electrochim Acta 31 977 [iii] Milchev A (1998) J Electroanal Chem 457 35, 47 [iv] Milchev A (2002) Electrocrystallization fundamentals of nucleation and growth. Kluwer, Boston... 

Deposition potential — is the required value to observe the appearance of a new phase in the course of a -> electrocrystallization process. See, - equilibrium forms of crystals and droplets, - nucleation and growth kinetics, -> nucleation overpotential. 

Reents B, Lacconi G, Plieth W (1994) Nucleation in the electrocrystallization process studied by surface-enhanced raman spectroscopy. J Electroanal Chem 376 185... 

Electrociystallization denotes nucleation and crystal growth in electrochemical sterns under the influence of an electric field [1.1-1.21]. Electrocrystallization of metals takes place at an electronic conducting substrate / ionic conducting electrolyte interface including, in general, three stages ... 

The fifth part deals with growth mechanisms of single crystal faces. The growth by 2D nucleation of quasi-perfect faces as well as the spiral growth mechanism of real crystal faces are discussed. Experimental verification is presented for the case of silver electrocrystallization. 

SERS may lead to detection techniques and assays with good sensitivity and selectivity. The area of electrocatalysis is continuously expanding. It has great potential in the area of electrochemical energy systems, especially fuel cells and batteries. The fundamental questions on nucleation, electrocrystallization, faceting, energy dissipation in hot metals and redox potential of nanoparticles are some of the issues that will remain the focus of immediate research. 

Galvanostatic reduction is another alternative for metal electrocrystallization in CPs. The metal nucleation and growth occurs at a continuously varying overpotential and therefore it is not suitable for gaining insight into the kinetics of the metal electrodeposition. Nevertheless, this approach provides a helpful opportunity to assess the involvement of CP reduction in the overall process, and to explore fine differences in the reductive behavior of CP materials synthesized under various electrochemical conditions [180-183,185,189]. 

Electrocrystallization (EC) is an electrochemical technique for use under liquids [93Prol]. It measures the variations in current associated with layer-by-layer growth of a dissolved ionic metal being reduced and deposited at an electrode surface. This method requires isolated surface sites that can reduce aqueous ions, and sites to which the reduced atoms can diffuse to nucleate the formation of a new atomic layer. When deposition occurs under critical potentials, layer growth is nearly instantaneous, yielding a current spike that marks the arrival of an atom at the nncleation site. This method works only for thoroughly studied surfaces that can be proven to grow by this mechanism. Spatial resolution has been reported at 5 pm. 

A MUchev, Electrocrystallization Fundamentals of Nucleation and Growth, Kluwer Academic Publishers, Boston, 2002. 

The nucleation and growth of organic thin films, and thin films in general, is challenging because it is difficult to initiate a nucleation process in a controlled manner. Furthermore, it is difficult to visualize these processes directly, particularly for growth processes occurring in a solution. The (ET)2X compounds, and other redox-active materials, can be grown by electrocrystallization, in which the ET molecule is oxidized at an electrode... 

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