PEMFC用亲水型薄层MEA的制备及其性能

本文提出一种新颖简易的方法制备PEMFC的亲水型薄层MEA,其阴、阳极催化层Pt担量分别为0. 4和 0. 2mg/cm2.实验发现,在亲水型MEA的表面上,有大量钟乳石状细微颗粒存在,从而使电极催化层的比表面积增大.在小电流密度区( <1A/cm2 ),亲水型MEA的极化性能差于Pt担量为 0. 7mg/cm2的疏水型常规MEA,但在大电流密度区( >2A/cm2 ),则前者的极化性能优化后者;亲水型MEA的最大输出比功率为1. 23W/cm2,高于疏水型电极的 1. 19W/cm2;在大电流密度区,亲水型MEA中的Pt电化学比活性也明显高于疏水型电极.

Fabricationand Propertiesof Hydrophilic Thin MEA Used in PEMFC

In this paper, a hydrophilic thin MEA with 0.4 mg/cm~2of Pt loading in a cathode was fabricated by a novel method, and its morphology and electrode performance were compared with those of a conventiona hydrophobicl MEA with 0.7mg/cm~2of Pt loading. Unlike the morphology of the conventional MEA, there were lots of stalactiticmicro-particles on the surface of the thin MEA, which increases the specificsurface of the catalyst layer in the electrode markedly. The electrochemical results showed that in the range of small current density (<1A/cm~2), the performance of the thin MEA was inferior to that of conventional MEA, while in the range of large current density (>2A/cm~2), the performance of the former was superior to that of the latter. The maximum specific power of the thin MEA was 1.23W/cm~2, which is higher than that of conventional MEA (1.19A/cm~2). Furthermore, the specific activity of Pt in thin MEA was higher than that of conventional MEA in the range of large current density.