Novel strategy to mitigate cathode catalyst degradation during air/air startup cycling via the atmospheric resistive switching mechanism of a hydrogen anode with a platinum catalyst supported on tantalum-doped titanium dioxide
Novel strategy to mitigate cathode catalyst degradation during air/air startup cycling via the atmospheric resistive switching mechanism of a hydrogen anode with a platinum catalyst supported on tantalum-doped titanium dioxide
复制标题
DOI：
10.1016/j.jpowsour.2015.06.072
复制
发表时间：
2015-10-30
影响因子：
9.2
通讯作者：
Uchida, Makoto
中科院分区：
文献类型：
--
作者：
Shintani, Haruhiko;Kojima, Yuya;Uchida, Makoto
我们提出了一种新的策略来缓解反向电流现象，利用金属氧化物半导体支架独特的“大气电阻开关机制”(ARSM)，使电阻率随着气体气氛的变化而变化。以Ta掺杂的二氧化钛负载铂作为阳极催化剂的膜电极组件(MEA)在空气中的电阻比在氢气中大一个数量级。氢氧化反应的过电位可以忽略不计，直到至少1.5A cm(-2)。使用铂/Ta-TiO2阳极可显著抑制阴极催化剂在空气/空气启动循环过程中的电化学活性表面积损失和碳腐蚀。降解率的降低归因于在空气中表现出高电阻率的阳极上的低氧还原反应速率导致的反向电流的减少。这些结果证明了ARSM在缓解空气/空气启动循环过程中阴极催化剂降解方面的有效性。(C)2015爱思唯尔B.V.保留所有权利。
We propose a new strategy for alleviating the reverse current phenomenon using a unique "atmospheric resistive switching mechanism" (ARSM) of a metal oxide semiconductor support, such that the electrical resistivity changes depending on the gas atmosphere. The membrane-electrode assembly (MEA) using Ta-doped TiO2-supported platinum (Pt/Ta TiO2) as the anode catalyst showed approximately one order of magnitude greater resistance in air than in hydrogen. The overpotential of the hydrogen oxidation reaction was negligible up to at least 1.5 A cm(-2). The losses of electrochemically active surface area and carbon corrosion of the cathode catalyst during air/air startup cycling were significantly suppressed by the use of the Pt/Ta-TiO2 anode. The decrease in the degradation is attributed to a reduction of the reverse current due to a low oxygen reduction reaction rate at the anode, which showed high resistivity in air. These results demonstrate the effectiveness of the ARSM in mitigating cathode catalyst degradation during air/air startup cycling. (C) 2015 Elsevier B.V. All rights reserved.