Chen Lina, Zhang Pengyang, Jin Yan-Qi, Yang Huijuan, Sheng Tian, Yan Yifan, Wang Tao, Chen Zhixin, Tian Na, Li Xifei, Zhou Zhi-You, Sun Shi-Gang
College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, and Tan Kah Kee Innovation Laboratory, Xiamen University, Xiamen 361005, China.
School of Materials Science and Engineering, Institute of Advanced Electrochemical Energy, Shaanxi International Joint Research Centre of Surface Technology for Energy Storage Materials, Xi'an University of Technology, Xi'an 710048, China.
Nano Lett. 2024 Aug 28;24(34):10642-10649. doi: 10.1021/acs.nanolett.4c02999. Epub 2024 Aug 19.
CO poisoning in Pt-based anode catalysts significantly hampers the proton exchange membrane fuel cell (PEMFC) performance. Despite great advances in CO-tolerant catalysts, their effectiveness is often limited to fundamental three-electrode systems, which is inadequate for practical PEMFC applications. Herein, we present a straightforward thermal oxidation strategy for constructing a Ru oxide blocking layer on commercial PtRu/C through a one-step Ru-segregation-and-oxidation process. The resulting 0.7 nm thick Ru oxide layer effectively inhibits CO adsorption while maintaining hydrogen oxidation activity. PtRu@RuO/C demonstrates exceptional CO tolerance, enduring 1% CO in rotating disk electrode tests, an ∼10-fold improvement compared to that of PtRu/C. Crucially, it retains high HOR activity and CO tolerance in PEMFC, with negligible polarization curve loss in the presence of 100 ppm CO. Notably, 85% HOR activity is retained after a 4 h stability test. This enhancement contributes to the Ru oxide layer decelerating CO adsorption kinetics, rather than promoting CO oxidation via the classic bifunctional mechanism.
基于铂的阳极催化剂中的一氧化碳中毒严重阻碍了质子交换膜燃料电池（PEMFC）的性能。尽管耐一氧化碳催化剂取得了巨大进展，但其有效性通常仅限于基本的三电极系统，这对于实际的PEMFC应用来说是不够的。在此，我们提出了一种直接的热氧化策略，通过一步Ru分离和氧化过程在商业PtRu/C上构建氧化钌阻挡层。所得的0.7纳米厚的氧化钌层在保持氢氧化活性的同时有效地抑制了一氧化碳的吸附。PtRu@RuO/C表现出卓越的一氧化碳耐受性，在旋转圆盘电极测试中能耐受1%的一氧化碳，与PtRu/C相比提高了约10倍。至关重要的是，它在PEMFC中保持了高氢氧化活性和一氧化碳耐受性，在存在100 ppm一氧化碳的情况下极化曲线损失可忽略不计。值得注意的是，经过4小时的稳定性测试后仍保留了85%的氢氧化活性。这种增强作用是由于氧化钌层减缓了一氧化碳的吸附动力学，而不是通过经典的双功能机制促进一氧化碳氧化。
