Platinum single-crystal electrodes

Egli WA, Visintin A, Triaca WE, Arvia AJ. The development of faceting and roughening at platinum pol5rfaceted single-crystal electrodes in a chloroplatinic acid solution. Appl Surf Sci 1993 68 583-93. 

Some measurements with Pt single-crystal faces have been published recently.140,210,773 Iwasita and Xia210 prepared platinum single crystals according to the method of Clavilier et a/.186 773 After flame annealing and cooling in an H2 + Ar mixture, the electrode was protected... 

Since oxidation of methanol is an electrocatalytic reaction with different adsorption steps, interactions of the adsorbed species with the metallic surface are important. Using platinum single-crystal electrodes, it has been proven that the electrooxidation of methanol is a surface-sensitive reaction. The initial activity of the Pt(llO) plane is much higher than that of the other low-index planes, but the poisoning phenomenon is so rapid that it causes a fast decrease in the current densities. The... 

Angelucci CA, Nart FC, Heirero E, Feliu JM. 2007a. Anion re-adsorption and displacement at platinum single crystal electrodes in CO-containing solutions. Electrochem Commun 9 1113-1119. 

Clavilier J. 1987. Pulsed linear sweep voltammetry with pulses of constant level in a potential scale, a polarization demanding condition in the study of platinum single crystal electrodes. J Electroanal Chem 236 87-94. 

Clavilier J, Sun SG. 1986. Electrochemical study of the chemisorbed species formed from formic acid dissociation at platinum single crystal electrodes. J Electroanal Chem 199 ... 

Clavilier J, Parsons R, Durand R, Lamy C, Leger JM. 1981. Formic acid oxidation on single crystal platinum electrodes. Comparison with polycrystalline platinum. J Electroanal... 

Garcia G, Koper MTM. 2008. Stripping voltammetry of carbon monoxide oxidation on stepped platinum single-crystal electrodes in alkaline solution. Phys Chem Chem Phys 10 3802-3811. 

Koper MTM, Schmidt TJ, MarkovicNM, Ross PN Jr. 2001. Potential oscillations and S-shaped polarization curve in the continuous electro-oxidation of CO on platinum single-crystal electrodes. J Phys Chem B 105 8381-8386. 

Lai SCS, Koper MTM. 2009. Electro-oxidation of ethanol and acetaldehyde on platinum single-crystal electrodes. Faraday Discuss 140 399-416. 

Lamy C, Leger JM, Clavilier J. 1982. Structural effects in the electrooxidation of methanol in alkahne medium. Comparison of platinum single crystal and polycrystalline electrodes. J Electroanal Chem 135 321-328. 

Xia XH, Liess HD, Iwasita T. 1997. Early stages in the oxidation of ethanol at low index single crystal platinum electrodes. J Electroanal Chem 437 233-240. 

Climent V, Gomez R, Orts JM, Aldaz A, Fehu JM. 1997. The potential of zero total charge of single-crystal electrodes of platinum group metals. In Korzeniewski C, Conway BE, eds. The Electrochemical Society Proceedings (Electrochemical Double Layer). Pennington, NJ The Electrochemical Society, pp. 222-237. 

Rodes A, Pastor E, Iwasita T. 1994. An FTIR study on the adsorption of acetate at the basal planes of platinum single-crystal electrodes. J Electroanal Chem 376 109-118. 

Park S, Wasileski SA, Weaver MJ. 2001. Electrochemical infrared characterization of carbon-supported platinum nanoparticles A benchmark structural comparison with single-crystal electrodes and high-nuclearity carbonyl clusters. J Phys Chem B 105 9719 -9725. 

Cyclic voltammetry studies of single-crystal platinum electrodes in acidic aqueous electrolytes showed that the two characteristic peaks of hydrogen adsorption/desorption on platinum (see Fig. 5.40) correspond in fact to reactions at two different crystal faces the peak at lower potential to Pt(100) and the other one to Pt(lll). 

Fig. 5.56 Triangular-pulse voltammograms of oxidation of 0.1 m formic acid in 0.5 m H2S04 at various faces of a single-crystal platinum electrode, 22°C, dE/dt =... 

We and others have been involved in the study of such systems including Cu/Au(lll),85 86 Ag/Au(lll),87 Pb/Ag(lll),88 and Cu/Pt(lll).89 The first three systems involved the use of epitaxially deposited metal films on mica as electrodes.90 92 Such deposition gives rise to electrodes with well-defined single-crystalline structures. In the last case a bulk platinum single crystal was employed. Because of the single-crystalline nature of the electrodes, polarization dependence studies could be used to ascertain surface structure. 

Adsorption of acetic acid on Pt(lll) surface was studied the surface concentration data were correlated with voltammetric profiles of the Pt(lll) electrode in perchloric acid electrolyte containing 0.5 mM of CHoCOOH. It is concluded that acetic acid adsorption is associative and occurs without a significant charge transfer across the interface. Instead, the recorded currents are due to adsorption/desorption processes of hydrogen, processes which are much better resolved on Pt(lll) than on polycrystalline platinum. A classification of adsorption processes on catalytic electrodes and atmospheric methods of preparation of single crystal electrodes are discussed. 

Case Studies Adsorption of Acetic Acid on Pt(111) Single Crystal Electrodes. Acetic acid is one of a very few organic compounds which is reversibly adsorbed on platinum at room temperature (20,25). We report below our radiochemical results on adsorption of this compound on Pt(111) and on polycrystalline Pt. 

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