Dual single-atom catalyst design to build robust oxygen reduction electrode via free radical scavenging
Dual single-atom catalyst design to build robust oxygen reduction electrode via free radical scavenging
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DOI：
10.1016/j.checat.2023.100532
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发表时间：
2023-03-16
期刊：
影响因子：
--
通讯作者：
Xing, Wei
中科院分区：
文献类型：
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作者：
Chu, Yuyi;Luo, Ergui;Xing, Wei
金属-氮-碳材料是氧还原反应中最有前途的铂替代催化剂。然而，缺乏有效的方法来提高耐久性，即，以科普原位形成的自由基、中心离子的浸出等的攻击。限制了这些催化剂的广泛应用。在这里，我们提出了一种新的，双金属，单原子催化剂设计（铁，铈-N-C），以面对最好的性能，但不稳定的Fe-N-C催化剂的可怕的失活问题。铈单中心被揭示为有效的化学催化剂，催化H2 O2反硝化成O2，导致增加的4 e选择性。此外，不是催化反应性中心点OH和中心点OOH物质的形成的Fe单位点，这些铈单位点主动消除原位产生的自由基。最终的Fe，Ce-N-C催化剂表现出超过Fe-N-C的优异耐久性。这为减缓Fe-N-C催化剂在酸性介质中的降解开辟了一条新的途径。
Metal-nitrogen-carbon materials are the most promising platinum replacement catalysts for oxygen reduction reaction. However, lacking an efficient approach to improve durability-i.e., to cope with the attack by in situ formed radicals, leaching of central ions, etc.-has limited these catalysts from widespread application. Here-in we present a novel, dual-metal, single-atom catalyst design (Fe,Ce-N-C) to confront the formidable deactivation issue of the best-performing yet unstable Fe-N-C catalysts. Cerium single sites are revealed as efficient chemical catalysts to catalyze the H2O2 disproportionation into O2, leading to increased 4e selectivity. Moreover, rather than Fe single sites that catalyze the formation of reactive center dot OH and center dot OOH species, these cerium single sites act pro-actively to eliminate in situ-generated radicals. The final Fe,Ce-N-C catalyst represents excellent durability exceeding that of Fe-N-C. This work opens a new path to alleviate the degradation of Fe-N-C catalysts in an acidic medium.