燃料电池多孔电极的电化学刻蚀处理及性能

Electrochemical etching and performance study of gas diffusion electrode for fuel cell application

采用电化学阴极刻蚀的方法对磁控溅射制备的铂气体扩散电极进行处理,考察了不同刻蚀电势和时间所制备样品的电化学行为。结果表明,与未刻蚀的电极相比,刻蚀后的电极电化学活性面积(ECSA)提高16.6%,氧还原半波电位正移15~20 mV,质量比活性(MA)和面积比活性(SA)分别提高27.2%和48.4%。X射线衍射光谱法(XRD)、透射电子显微镜法(TEM)等物性表征表明刻蚀后的电极中铂的晶型并未改变,但其分散性和颗粒形状有所变化,推测为电极电化学活性面积提高,因此提高了电极氧还原性能。

Electrochemical cathodic etching was used for platinum gas diffusion electrode prepared by prepared by magnetron sputtering. The electrochemical behavior of the samples prepared by different etching potentials and time was investigated. The results show that compared to untreated electrode, the electrochemical active surface area of the electrode after etching is increased by 16.6%, and the oxygen reduction half-wave potential is positively shifted by 15~20 mV. The MA and SA of the etched electrode are increased by 27.2% and 48.4%. The physical properties of XRD and TEM indicate that the crystal phase of platinum in the electrode isn’t changed. The dispersion and particle shape are changed, then the electrochemical active area is enhanced. And the oxygen reduction performance of the electrode is enhanced.