Comparative study of methanol crossover across electropolymerized and commercial proton exchange membrane electrolytes for the acid direct methanol fuel cell

The methanol crossover properties of various membrane electrolytes are shown to be measurable by means of a modified differential electrochemical mass spectrometry (DEMS) [Bittins-Cattaneo, B., Cattaneo, E., Königshoven, P. and Vielstich, W., in Electroanalytical Chemistry, Vol. 17, ed. A. J. Bard, Marcel Dekker, New York, 1991, p. 181; Wolter, O., Giordano, M. C., Heitbaum, J., Vielstich, W., O'Grady, W. E., Ross, P. N. and Will, F. G. (Eds.), Proc. Symp. Electrocatalysis, Minneapolis 1981. PV 82-2, The Electrochemical Society, Pennington, NJ, 1982, p. 235.] technique using experimental electrodes and gas-diffusion electrodes. Electrochemically synthesized crosslinked substituted polyoxyphenylene (POP) films on gold and platinized carbon supports were the targets of electrode modifications and a screening study of these polymers and commercially available ion exchange membranes was carried out. POP-like polymers are expected to be an essential ingredient in future crossover minimization strategies.