Lin Liu, Xu Yunming, Han Yiting, Xu Ruikun, Wang Tongyue, Sun Zemin, Yan Zhenhua
College of Arts and Sciences & Center for Advanced Materials Research, Beijing Normal University, Zhuhai 519087, China.
State Key Laboratory of Advanced Chemical Power Sources, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (RECAST), College of Chemistry, Nankai University, Tianjin 300071, China.
J Am Chem Soc. 2024 Mar 20;146(11):7363-7372. doi: 10.1021/jacs.3c11907. Epub 2024 Mar 7.
A deep understanding of the mechanism for the spin-magnetic effect on O-H cleavage is crucial for the development of new catalysts for water oxidation. Herein, we designed and synthesized the crystalline Fe-DABDT and Co-DABDT (DABDT = 2,5-diaminobenzene-1,4-dithiol) and optimized an effective magnetic moment to explore the role of the spin-magnetic effect in the regulation of water oxidation activity. It can be found that the OER activity of the catalyst is positively correlated with its effective magnetic moment. Under the external magnetic field, Fe-DABDT with more spin single electrons has a stronger spin-magnetic response to water oxidation than Fe/Co-DABDT and Co-DABDT. The increase in OER current of Fe-DABDT is nearly 2 times higher than that of Co-DABDT. Experimental and density functional theory studies show that magnetized Fe sites could realize nucleophilic reaction, accelerate the polarization of electron spin states, and promote the polar decomposition of O-H and the formation of the O-O bond. This study provides mechanistic insight into the spin-magnetic effect of oxygen evolution reaction and further understanding of the spin origin of catalytic activity, which is expected to improve the energy efficiency of hydrogen production.
深入理解自旋磁效应在O-H键断裂中的作用机制对于开发新型水氧化催化剂至关重要。在此，我们设计并合成了晶体Fe-DABDT和Co-DABDT（DABDT = 2,5-二氨基苯-1,4-二硫醇），并优化了有效磁矩，以探索自旋磁效应在调节水氧化活性中的作用。可以发现，催化剂的析氧反应（OER）活性与其有效磁矩呈正相关。在外部磁场下，具有更多自旋单电子的Fe-DABDT对水氧化的自旋磁响应比Fe/Co-DABDT和Co-DABDT更强。Fe-DABDT的OER电流增加量比Co-DABDT高出近2倍。实验和密度泛函理论研究表明，磁化的Fe位点可实现亲核反应，加速电子自旋态的极化，并促进O-H的极性分解和O-O键的形成。本研究为析氧反应的自旋磁效应提供了机理见解，并进一步理解了催化活性的自旋起源，有望提高制氢的能量效率。
