南开大学严振华团队报道了d-π共轭聚合物在水氧化中增强O-H裂解的自旋磁效应。相关研究成果发表在2024年3月7日出版的《美国化学会杂志》。

深入了解O–H裂解的自旋磁效应机制对于开发新的水氧化催化剂至关重要。

该文中，研究人员设计并合成了结晶的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OER活性与其有效磁矩呈正相关。在外磁场作用下，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电流的增加是Co-DABDT近2倍。

实验和密度泛函理论研究表明，磁化的Fe位点可以实现亲核反应，加速电子自旋态的极化，促进O–H的极性分解和O–O键的形成。

该项研究为析氧反应的自旋磁效应提供了机制上的见解，并进一步了解了催化活性的自旋起源，有望提高制氢的能源效率。

附：英文原文

Title: Spin-Magnetic Effect of d-π Conjugation Polymer Enhanced O–H Cleavage in Water Oxidation

Author: Liu Lin, Yunming Xu, Yiting Han, Ruikun Xu, Tongyue Wang, Zemin Sun, Zhenhua Yan

Issue&Volume: March 7, 2024

Abstract: 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.

DOI: 10.1021/jacs.3c11907

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.3c11907