Wang Tao, Li Lai-Yang, Chen Li-Na, Sheng Tian, Chen Luning, Wang Yu-Cheng, Zhang Pengyang, Hong Yu-Hao, Ye Jinyu, Lin Wen-Feng, Zhang Qinghua, Zhang Peng, Fu Gang, Tian Na, Sun Shi-Gang, Zhou Zhi-You
Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces, Tan Kah Kee Innovation Laboratory, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, PR China.
College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, PR China.
J Am Chem Soc. 2022 Jun 1;144(21):9292-9301. doi: 10.1021/jacs.2c00602. Epub 2022 May 20.
CO poisoning of Pt-group metal catalysts is a long-standing problem, particularly for hydrogen oxidation reaction in proton exchange membrane fuel cells. Here, we report a catalyst of Ru oxide-coated Ru supported on TiO (Ru@RuO/TiO), which can tolerate 1-3% CO, enhanced by about 2 orders of magnitude over the classic PtRu/C catalyst, for hydrogen electrooxidation in a rotating disk electrode test. This catalyst can work stably in 1% CO/H for 50 h. About 20% of active sites can survive even in a pure CO environment. The high CO tolerance is not via a traditional bifunctional mechanism, i.e., oxide promoting CO oxidation, but rather via hydrous metal oxide shell blocking CO adsorption. An ab initio molecular dynamics (AIMD) simulation indicates that water confined in grain boundaries of the Ru oxide layer and Ru surface can suppress the diffusion and adsorption of CO. This oxide blocking layer approach opens a promising avenue for the design of high CO-tolerant electrocatalysts for fuel cells.
铂族金属催化剂的一氧化碳中毒是一个长期存在的问题，特别是在质子交换膜燃料电池中的氢氧化反应方面。在此，我们报道了一种负载在TiO上的氧化钌包覆钌催化剂（Ru@RuO/TiO），在旋转圆盘电极测试中用于氢电氧化时，它能够耐受1 - 3%的一氧化碳，比经典的PtRu/C催化剂的耐受性提高了约2个数量级。这种催化剂在1% CO/H₂中能稳定工作50小时。即使在纯一氧化碳环境中，约20%的活性位点仍能存活。高一氧化碳耐受性并非通过传统的双功能机制，即氧化物促进一氧化碳氧化，而是通过含水金属氧化物壳层阻止一氧化碳吸附。从头算分子动力学（AIMD）模拟表明，限制在氧化钌层和钌表面晶界中的水能够抑制一氧化碳的扩散和吸附。这种氧化物阻挡层方法为设计用于燃料电池的高一氧化碳耐受性电催化剂开辟了一条有前景的途径。
