Abstract: Several factors including temperature, potential, and intermediates that influence the performance of electrocatalysts in direct methanol fuel cells were examined. The results show that the sintering process of Pt catalyst particles was accelerated at high temperatures, and for PtRu catalysts, this process was largely inhibited by ruthenium oxides/hydroxides. The alloying degree of PtRu catalysts was elevated to some extent after the discharge test at a high temperature. The degradation of electrocatalysts was accelerated by high potential. The methanol oxidation reaction was hindered to some extent by intermediates such as formic acid and formaldehyde, especially the latter.

Key words: direct methanol fuel cell, electrocatalyst, performance degradation, temperature, potential