On-line alleviation of poisoning in direct methanol fuel cells with pulse potential strategy
On-line alleviation of poisoning in direct methanol fuel cells with pulse potential strategy
复制标题
脉冲电位策略在线缓解直接甲醇燃料电池中毒
DOI：
10.1016/j.jpowsour.2019.02.025
复制
发表时间：
2019
影响因子：
9.2
通讯作者：
Sun Gongquan
中科院分区：
文献类型：
--
作者：
Sun Xuejing;Yang Linlin;Xia Zhangxun;Sun Hai;Sun Gongquan
工业级甲醇中的杂质对催化剂的毒害是直接甲醇燃料电池低成本大规模应用的一大挑战。在这项工作中，我们系统地研究了杂质对电池性能的影响，并确认了由于杂质的部分电氧化而产生的含有羰基的中间物种的吸附是导致电池性能下降的关键因素。因此，提出了间歇施加脉冲电位(阳极上的还原电位或阴极上的氧化电位)的在线减缓策略。外加电势会在阳极上形成还原条件，通过还原吸附在铂-Ru电催化剂上的羰基物种来释放活性中心。基于该策略的直接甲醇燃料电池能有效地抑制含羰基中间体的吸附，其衰变速率比传统操作下的单电池下降近两个数量级，为工业级甲醇原料直接甲醇燃料电池的实际应用奠定了基础。
Catalyst poisoning from the impurities in the industrial grade methanol is a major challenge for the large-scale application of direct methanol fuel cells in low cost. In this work, we systematically investigate the impurities influencing on cell performance, and confirm that the adsorption of carbonyl containing intermediate species derived from the partial electro-oxidation of the impurities is a crucial factor leading to performance degradation. Hence, an on-line alleviation strategy by intermittently applying pulse potential (reduction potential on the anode or oxidation potential on the cathode) is proposed. The applied potential will bring a reductive condition on the anode, which releases the active sites via the reduction of carbonyl containing species adsorbed on platinum-ruthenium electro-catalysts. Based on this strategy, the adsorption of carbonyl containing intermediate species are effectively suppressed, and the decay rate declines by nearly two orders of magnitude than that of a single cell under traditional operation, which paves a way for the practical application of direct methanol fuel cells with industrial grade methanol feed.