An alternating pulse electrochemical methanol concentration sensor for direct methanol fuel cells

An electrochemical methanol concentration sensor using an alternating pulse working voltage was developed for direct methanol fuel cells. The sensor was constructed based on the membrane electrode assemblies of fuel cells, but its two electrodes have the same structure and components, and methanol solution was fed into both of the electrodes simultaneously. Owing to the alternating pulse voltage and the special structure of the sensor, methanol oxidation and proton reduction reactions occur alternately at each of the two electrodes, which is favorable for self-cleaning the electrode surface and maintaining a catalytically active surface.