Galvanostatic pulse electrodeposition

Coutanceau C, Rakotondrainibe AF, Lima A, Gamier E, Pronier S, Leger JM, Lamy C. 2004. Preparation of Pt-Ru bimetallic anodes by galvanostatic pulse electrodeposition characterization and appbcation to the direct methanol fuel cell. J Appl Electrochem 34 61-66. 

FIGURE 9.10 TEM image of a Pt0 65Ru035/C catalyst prepared by galvanostatic pulse electrodeposition with t0ff= 2.5 s. 

Conditions of Catalyst Preparation by Galvanostatic Pulse Electrodeposition and... 

The bath composition, the pH-value, the hydrodynamic conditions and also the use of special current pulse shapes are further possibilities to influence the deposition process. It is advantageous to perform the pulsed electrodeposition in the galvanostatic mode because the average deposition rate can be simply derived from... 

Yang C-C, Cheh HY (1995) Pulsed electrodeposition of copper/nickel multilaycas on a rotating disk electrode I. Galvanostatic deposition. J Electrochem Soc 142 3034—3040... 

Figure 3. Generalized double galvanostatic pulse used to electrodeposit superlattices. The superlattices could also be deposited by modulating either the potential or mass-transport.

For example, if Qi = 50 tF/cm and R = 2 fi, t = 4.6 X 10 " s (0.46 ms). Thus, in the galvanostatic transient technique, the duration of the input current density pulse is on the order of milliseconds. From a series of measurements of for a set of i values, one can construct the current-potential relationship for an electrochemical process. For example. Figure 6.20 shows the current-potential relationship for the electrodeposition of copper from acid CUSO4 solution. 

Another comphcation arises from the fact that, in contrast to conventional electrodes, CP-coated electrodes often undergo changes in their oxidation state and structure in the course of metal electrodeposition. This is usually the case when driving metal-ion reduction by means of the most fiequently applied electrochemical techniques - cyclic voltammetry, multistep potential procedures, repetitive square-wave potential (or pulse potentiostatic) techniques, and galvanostatic reduction (Figure 7.3). In spite of the difficulty in... 

The electrodeposition process can either occur under potential (potentiostatic deposition) or current (galvanostatic deposition) control. In practice, the common approach is to control the deposition flux (current) in order to obtain the deposit with desired thickness and properties. The electrodeposition under galvanostatic control can be executed as either the constant current process or using some more complex currenttime function profile. In the latter case, the electrodeposition process is commonly called the pulse current deposition and it has been widely used in industrial and academic applications. The typical pulse current function has the simple on/off profile shown in Fig. 11. ... 

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