Potentiostatic current transient

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. 

As mentioned in potentiostatic current transient method, when the fractal dimension is determined by using diffusion-limited electrochemical technique, the diffusion layer length acts as a yardstick length.122 In the case of cyclic voltammetry, it was... 

In practical application, it was reported that the platinum particles dispersed in highly porous carbonized polyacrylonitrile (PAN) microcellular foam used as fuel-cell electrocatalyst160 have the partially active property. The fractal dimension of the platinum particles was determined to be smaller than 2.0 by using the potentiostatic current transient technique in oxygen-saturated solutions, and it was considered to be a reaction dimension, indicating that not all of the platinum particle surface sites are accessible to the incoming oxygen molecules. 

Diagnostic Relationships Between Current, Maximum Current, and Time. Scharifker and Hills (26) developed a theory that deals with the potentiostatic current transients for 3D nucleation with diffusion-controlled growth. According to this theory, the theoretical diagnostic relationship in a nondimensional form is given by... 

Fig. 29. Electrodeposition of Ag from 0.017 M AgCN + 0.92 M KCN + 0.11 M K2CO3 solution dimensionless analysis of experimental potentiostatic current transients (/, and tm are the current and time corresponding to the maximum on the current transient curve, respectively). Upper curve calculated for the instantaneous nucleation mechanism lower curve, for the progressive nucleation mechanism. Different symbols/experimental points relating to different potentials [136], Reproduced by permission of The Electrochemical Society, Inc.

Fig. 12.8. Potentiostatic current transient (d) for the reduction of Au/quartz modified electrode with Os,(bpy)2py-PAA hydrogel in 0.1 M KNO, 50 mM TRIS buffer of pH 7.2 and 0.1 M glucose, for a potential step from 0 V to 0.56 V V (SCE) (c) and simultaneous time evolution of XLf (a) and Rf (b) components of the quartz impedance at 10 MHz.

Monatomic steps at real surfaces do significantly influence not only the nucleation act, but also the spreading and overlapping of 2D islands, which determine the shape of potentiostatic current transients. Neglecting the adsorptive contribution in eq. (3.64), i.e., ep Qcd, and assuming a barrierless nucleation and growth of a condensed 2D Mcads phase only at steps with a regular pattern characterized by a... 

Jung, K.-N., and Pyun, S.-I. 2006b. The cell-impedance-controlled lithium transport through LiMn2O4 film electrode with fractal surface by analyses of ac-impedance spectra, potentiostatic current transient and linear sweep voltammograms. Electrochimica Acta 51, 4649 658. 

The potentiostatic current transient (PCT) technique has been known as the most popular method to understand lithium transport through an intercalation electrode, based on the assumption that lithium diffusion in the electrode is the rate-determining process of lithium intercalation/deintercalation [45]. By solving Eick s second equation for planar geometry with I.C. in Equation (5.28), impermeable B.C. in Equation (5.29), and potentiostatic B.C. 

Nikolic ND, Popov KI, Ivanovic ER, Brankovic G, Stevanovic SI, Zivkovic PM (2015) The potentiostatic current transients and the role of local diffusion fields in formation of the 2D lead dendrites from the concentrated electrolyte. J Electroanal Chem 739 137-148... 

It was noticed that, although in the polarisation diagram passivity is maintained at -530 and -520 mV, respectively, potentiostatic current transient plots show very high positive current densities of 21 mA/cm and 6.5 mA/cm, respectively. However, when the panels were passivated in same solutions by applying instantaneously potentials of -820 and -800 mV, current densities of -1.6 and -6.25 mA/cm were, respectively, obtained as shown in Figs. 4.8a, b. 

Potentiostatic current transient (PSCT) plots as shown in Figs. 4.21 and 4.22 showed higher current densities of 9 mA/cm and 40 mA/cm when passivated at -1146 and -1610 mV, respectively. 

Potentiostatic current transients Surface reactivity, etch-chemistry, efficiencies of corrosion inhibitors Hong et al. (2005a), Surisetty et al. (2008)... 

Potentiostatic current transient measurements for testing individuai siurry additives... 

To design slurry compositions for metal CMP, usually it is necessary to determine if and how the individual additives would affect the faradaic activity of the selected metal surface. The potentiostatic current transient technique, usually combined with measurements of OCP transients, is useful for performing such tests. Figure 3.13 displays a set of experimental results to demonstrate this approach. Here the CMP metal is Cu,... 

Scharifker, B.R., Mostany, J., Palomar-Pardave, M. and Gonzalez, I. (1999) On the theory of the potentiostatic current transient for diffusion-controlled three-dimensional electrocrystallisation processes. Journal of the Electrochemical Society, 146, 1005-1012. 

Figure 11a shows some potentiostatic current transients for iron in solutions with and without Q . Below the pitting potential, the two curves are coincident. Above the pitting potential, after a certain anodization time, the two curves are seen to deviate. 

Lee, J.-W. Pyun, S.-I. (2005). A Study on the Potentiostatic Current Transient and Linear Sweep Voltammogram Simulated from Fractal Intercalation Electrode Diffusion... 

K. N. Jung and S. I. Pyun, Electrochim. Acta, 52, 2009 (2007). Theoretical Approach to Cell-Impedance-Controlled Lithium Transport through Lij Mu204 Film Electrode with Partially Inactive Fractal Surface by Analyses of Potentiostatic Current Transient and Linear Sweep Voltammogram. 

In open-circuit conditions, metastable pitting results in rest potential fluctuations as well, although this question is less documented in the literature than the potentiostatic current transients. Analyzing the PSD of the rest potential fluctuations on a 304 type steel, some authors evidenced however two results of great metallurgical importance (a) The potential fluctuations are more pronounced for cold-rolled specimens than for solution-annealed ones, and (b) in the 0.05-2 Hz frequency range, the PSD amplitude increases with the steel sulfur content. 

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