Hydrogen Passivation of M–N–C (M = Fe, Co) Catalysts for Storage Stability and ORR Activity Improvements,Advanced Materials

当前位置： X-MOL 学术 › Adv. Mater. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Hydrogen Passivation of M–N–C (M = Fe, Co) Catalysts for Storage Stability and ORR Activity Improvements
Advanced Materials ( IF 27.4 ) Pub Date : 2021-08-08 , DOI: 10.1002/adma.202103600
Jieyuan Liu ₁ , Xin Wan ₁ , Shiyuan Liu ₁ , Xiaofang Liu ₁ , Lirong Zheng ₂ , Ronghai Yu ₁ , Jianglan Shui ₁

Affiliation

M–N–C (M = Fe, Co) are highly active nonprecious metal electrocatalysts for the oxygen reduction reaction (ORR) and other applications. Although their operation stability has been extensively studied in proton-exchange-membrane fuel cells, the storage stability that determines the performance maintenance before use has not yet been understood. Here, it is found that long-term exposure of M–N–C catalysts in air would cause surface oxidation and hydroxylation, resulting in significant decrease of ORR activity and fuel-cell performances. Hydrogen passivation is demonstrated to be an effective strategy to protect the atomic M–N₄ active sites and improve the storage stability of the catalysts. In addition, the hydrogen-termination can also reduce the ORR energy barrier and increase the utilization of active sites, leading to the improvements of fuel-cell activity and power density. Notably, these findings help to understand the storage-associated degradation and protection of M–N–C catalysts.

中文翻译：

M-N-C (M = Fe, Co) 催化剂的氢钝化以提高储存稳定性和 ORR 活性

M-N-C (M = Fe, Co) 是用于氧还原反应 (ORR) 和其他应用的高活性非贵金属电催化剂。尽管它们的运行稳定性已在质子交换膜燃料电池中得到广泛研究，但尚未了解决定使用前性能维持的储存稳定性。在这里，发现 M-N-C 催化剂长期暴露在空气中会导致表面氧化和羟基化，导致 ORR 活性和燃料电池性能显着降低。氢钝化被证明是保护原子 M-N ₄的有效策略活性位点，提高催化剂的储存稳定性。此外，氢封端还可以降低 ORR 能垒并提高活性位点的利用率，从而提高燃料电池的活性和功率密度。值得注意的是，这些发现有助于了解 M-N-C 催化剂的存储相关降解和保护。

更新日期：2021-09-21

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11