Abstract
Current efficiencies for the formation of CO2 during methanol oxidation at smooth polycrystalline platinum electrodes were determined by differential electrochemical mass spectrometry in a thin layer flow through cell. In all cases, the current efficiencies are below 60%; in particular, values as low as 16% were found in 0.1 M methanol solution at 0.6 V, which shows that a large amount of soluble intermediates (formaldehyde and/or formic acid) are formed. The extent to which these soluble intermediates are further oxidized to CO2 depends on the diffusion conditions. For methanol oxidation a parallel oxidation path via COad is also active. The influence of the surface crystal structure and, in particular, of steps was also studied. Step decoration by foreign metals allowed examination of the effect of cocatalytic metals on well defined model surfaces.
Similar content being viewed by others
References
E. Herrero, K. Franaszczuk and A. Wieckowski, J. Phys. Chem. 98 (1994) 5074.
E. Herrero, W. Chrzanowski and A. Wieckowski, J. Phys. Chem. 99 (1995) 10423.
T.D. Jarvi and E.M. Stuve, 'Fundamental Aspects of Vacuum and Electrocatalytic Reactions of Methanol and Formic Acid on Platinum Surfaces, in J. Lipkowski and P.N. Ross (Eds.), 'Electrocatalysis' (Wiley-VCH, New York, 1998), p. 75.
W. Vielstich and X.H. Xia, J. Phys. Chem. 99 (1995) 10421.
W. Vielstich, 'Fuel Cells. Modern Processes for the Electrochemical Production of Energy' (Wiley-Interscience, London New York, 1965).
C. Korzeniewski and C. Childers, J. Phys. Chem. B 102 (1998) 489.
S. Wasmus, J.-T. Wang and R.F. Savinell, J. Electrochem. Soc. 142 (1995) 3825.
P. Berenz, S. Tillmann, H. Massong and H. Baltruschat, Electrochim. Acta 43 (1998) 3035.
H. Massong, S. Tillmann, T. Langkau, E.A. Abd El Meguid and H. Baltruschat, Electrochim. Acta 44 (1998) 1379.
J. Shin and C. Korzeniewski, J. Phys. Chem. 99 (1995) 3419.
C. Lamy, J.M. Leger, J. Clavilier and R. Parsons, J. Electroanal. Chem. 150 (1983) 71.
X.H. Xia, T. Iwasita, F. Ge and W. Vielstich, Electrochim. Acta 41 (1996) 711.
E. Herrero, K. Franaszczuk and A. Wieckowski, J. Phys. Chem. 98 (1994) 5074.
Z. Jusys, H. Massong and H. Baltruschat, J. Electrochem. Soc. 146 (1999) 1093.
H. Baltruschat and U. Schmiemann, Ber. Bunsenges. Phys. Chem. 97 (1993) 452.
H. Baltruschat, Differential electrochemical mass spectrometry as a tool for interfacial studies, in A. Wieckowski (Ed.), 'Interfacial Electrochemistry' (Marcel Dekker, New York, 1999), p. 577.
H. Massong, H. Wang, G. Samjeské and H. Baltruschat, Electrochim. Acta 46 (2000) 701.
D.R. Storm and J.D.E. Koshland, J. Am. Chem. Soc. 94 (1972) 5805.
H.A. Gasteiger, N. Markovic, P.N. Ross and E.J. Cairns, J. Phys. Chem. 97 (1993) 12020.
X. Ren, M.S. Wilson and S. Gottesfeld, J. Electrochem. Soc. 143 (1996) L12.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Wang, H., Löffler, T. & Baltruschat, H. Formation of intermediates during methanol oxidation: A quantitative DEMS study. Journal of Applied Electrochemistry 31, 759–765 (2001). https://doi.org/10.1023/A:1017539411059
Issue Date:
DOI: https://doi.org/10.1023/A:1017539411059