Design of a MEA with multi-layer electrodes for high concentration methanol DMFCs

According to the conventional MEA test, methanol and water crossover are the main factors to determine performance of a passive DMFC. Thus, to ensure the high cell performance of a passive DMFC using high concentration methanol of 50–95 vol%, the MEA in this study introduces the barrier layer to limit the crossover of high concentration methanol, a hydrophobic layer to reduce water crossover, and a hydrophilic layer to enhance the water recovery from the cathode to the anode. The functional layers of the MEA have the effect of improving the performance of the passive DMFC by decreasing the methanol and water crossover. In spite of the operation with 95 vol% methanol, the MEA with multi-layer electrodes for high concentration methanol DMFCs shows a maximum power density of 35.1 mW cm−2 and maintains a high power density of 30 mW cm−2 (0.405 V) under constant current operation.

► A new MEA design for high concentration methanol DMFCs. ► A multi-layer electrode of the anode to reduce the methanol and water crossover from the anode to the cathode. ► A Vulcan XC-72/Nafion layer of the cathode to enhance the water back diffusion from the cathode to the anode. ► A high power density of 35.1 mW cm−2 for operation with 95 vol% methanol.