Wu Haihua, Li Yudan, Li Haobo, Wu Feng, Li Lihong, Xu Xin, Gao Yunfang
State Key Laboratory Breeding Base of Green-Chemical Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, China.
School of Chemical Engineering, The University of Adelaide, Adelaide, SA, 5005, Australia.
Small. 2024 Nov;20(44):e2404065. doi: 10.1002/smll.202404065. Epub 2024 Jul 1.
FeO is barely taken into account as an electrocatalyst for oxygen reduction reaction (ORR), an important reaction for metal-air batteries and fuel cells, due to its sluggish catalytic kinetics and poor electron conductivity. Herein, how strain engineering can be employed to regulate the local electronic structure of FeO for high ORR activity is reported. Compressively strained FeO shells with 2.0% shortened Fe─O bond are gained on the Fe/FeN cores as a result of lattice mismatch at the interface. A downshift of the d-band center occurs for compressed FeO, leading to weakened chemisorption energy of oxygenated intermediates, and lower reaction overpotential. The compressed FeO exhibits greatly enhanced electrocatalytic ORR activity with a kinetic current density of 27 times higher than that of pristine one at 0.80 V (vs reversible hydrogen electrode), as well as potential application in zinc-air batteries. The findings provide a new strategy for tuning electronic structures and improving the catalytic activity of other metal catalysts.
由于其缓慢的催化动力学和较差的电子导电性，氧化亚铁作为氧还原反应（ORR）的电催化剂几乎未被考虑，而氧还原反应是金属空气电池和燃料电池的重要反应。在此，报告了如何采用应变工程来调节氧化亚铁的局部电子结构以实现高ORR活性。由于界面处的晶格失配，在铁/氮化铁核上获得了具有2.0%缩短铁-氧键的压缩应变氧化亚铁壳层。压缩后的氧化亚铁d带中心下移，导致含氧中间体的化学吸附能减弱，反应过电位降低。压缩后的氧化亚铁表现出大大增强的电催化ORR活性，在0.80 V（相对于可逆氢电极）时的动力学电流密度比原始氧化亚铁高27倍，并且在锌空气电池中具有潜在应用。这些发现为调整电子结构和提高其他金属催化剂的催化活性提供了一种新策略。
