Formic acid oxidation experimental oscillations

Fig. 53. (a) Cyclic voltammogram during the formic acid oxidation on a Bi-modified Pt ring electrode scan rate 5mV s-1. The change in the oscillation form close to t = 73.7 s (i.e. U = 0.16 V) indicates a qualitative change in the dynamics, (b) Spatio-temporal profile of the interfacial potential in the transition region of the oscillation form in (a). For the experimental set-up, see Fig. 49b. (Reproduced from J. Lee, J. Christoph, P. Strasser, M. Eiswrith and G. Ertl, J. Chem. Phys. (2001) 115, 1485 by permission of the American Institute of Physics.)...

Potential oscillations during formic acid oxidation had been observed already in the 1920s [126]. As Fig. 32 shows [127], the upper potential limit is between 800 and 900 mV, as in the case of H2/CO oscillations. Introducing a model simulation, only the four (or five) rate constants of Eqs. (12-14) have to be employed. This has been done quite successfully by Okamoto and coworkers [128], reproducing the fingerprints of their experimental results. 

Inzelt Gy, Kertesz V. Experimental evidence for the periodical changes of the amoimt of chemisorbed species accompanying oscillations produced in the coiuse of galvanostatic oxidation of formic acid on platinum. Electrochim Acta 1993 38 2385-6. 

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