Pell and Conway

Figure 4.5.31. Cyclic voltammogram for a gold-wire brush electrode at 20mVs" in comparison with that for a single gold wire electrode on a normalized identical current-response scale (from Pell and Conway [2001]).

The mechanism of a oxide film formation on gold in aqueous acid solution had been discussed in detail by Conway [40] and Tian, Pell, and Conway [41], Monolayer oxide formation on gold in base commences at a lower potential (on the RHE scale) than in acid (ca. 1.20 V in base versus ca. 1.36 V in acid [23,42]). Similar behavior was observed with both Pd [42] and Pt [43], and the effect was attributed to the fact that the initial reaction involves active metal atoms which on oxidation yield significantly hydrated, anionic oxyspecies. Vigorous, steady-state oxygen gas evolution occurs on gold in aqueous media only above ca. 2.0 V [44],... 

Liu, T. C., W. G. Pell, and B. E. Conway. 1997. Self-discharge and potential recovery phenomena at thermally and electrochemically prepared RuOj supercapacitor electrodes. Electrochimica Acta 42 3541-3552. 

FIG U RE 2.3 Ragone plots for the fully charged carbon-cloth electrode for various constant currents as marked on the figure for four electrolyte eoncentrations 0.01 M ( ), 0.05 M ( ), 0.5 M (A), and 5 M (t). (Reprinted from Journal of Power Sources, 156, Niu, J., W. G. Pell, and B. E. Conway, Requirements for performance characterization of C double-layer supercapacitors Applications to a high specific-area C-cloth material, 725-740, Copyright 2006, with permission from Elsevier.)... 

W. G. Pell and B. E. Conway, Peculiarities and requirements of asymmetric capacitor devices based on combination of capacitor and battery-type electrodes, /. Power Sources 136,2004,334-345. 

Pell, W.G, and B.E, Conway, Analysis of power limitations at porous supercapacitor electrodes under cyclic voltammetry modulation and dc charge. Journal of Power Sources, 2001. 96 pp, 57-67... 

Conway, B. E., and W. G. Pell. 2003. Double-layer and pseudocapacitance types of electrochemical capacitors and their applications to the development of hybrid devices. Journal of Solid State Electrochemistry 7 637-644. 

Brian E. Conway wishes to thank Dr. W.G. Pell, Senior Research Associate in his group, for many useful discussions on impedance spectroscopy and voltammetry of electrochemical capacitors, as published in detail in journal papers elsewhere. Acknowledgement is also made to the Natural Sciences and Engineering Research Council of Canada for support of that work, which has led to the present contribution. 

W. G. Pell, B. E. Conway, W. A. Adams, and J. de Oliveria [1999] Electrochemical Efficiency in Multiple Discharge/Recharge Cycling of Supercapacitors in Hybrid EV Applications, J. Power Sources 80, 134-141. 

Conway BE, Pell WG (2002) Powct limitations of supercapacitor operation associated with resistance and capacitance distribution in praous electrode devices. J Power Sources 105 169... 

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