DMFC阳极催化层结构优化研究

OPTIMIZATION OF THE ANODE CATALYST LAYER IN MEA DIRECT METHANOL FUEL CELL

直接甲醇燃料电池阳极催化层是甲醇电化学氧化的场所,并承担着将甲醇氧化成的二氧化碳排出的作用,因此提高直接甲醇燃料电池阳极的性能对于整体性能的提高有着至关重要的作用.该文采用喷雾法制备了膜电极,并在阳极催化层中加入了不同含量的NH4HCO3作为阳极造孔剂,用以改变阳极催化层的微结构.实验结果表明,阳极催化层加入造孔剂后性能比未加入造孔剂有很大提高,加入造孔剂的量为50%时性能最好,最高性能从未加入造孔剂的111 mW/cm2提高到156 mW/cm2.SEM表明,加入造孔剂后阳极表面的空隙率提高,这有助于传质的增加和二氧化碳的排出.

The anode catalyst layer of direct methanol fuel cell effect on not only the oxidation of methanol but also elimination of CO2.In this paper,membrane electrode assembly（MEA） was prepared by spraying method.NH4HCO3 was added into the anode catalyst to optimize the micro-structure of the catalyst layer.The results indicated that the performance of MEA with NH4HCO3 in anode catalyst layer was better than MEA without NH4HCO3.The performance of MEA with a optimized capacity 50 wt% achieved 156 mW/cm2.The SEM also showed that the increase of micro-cracks in the anode catalyst layer helps to mass transfer and elimination of CO2.