Lv Ze, Shu Zheng, Qiu Yang, Luo Jiawei, Xu Kaibing, Ma Yimeng, Zhang Linping, Xu Hong, Mao Zhiping
National Engineering Research Center for Dyeing and Finishing of Textiles, College of Chemistry and Chemical Engineering, Donghua University, No.2999 North Renmin Road, Shanghai, 201620, China.
Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering University of Macau, Macao SAR, 999078, China.
Adv Sci (Weinh). 2025 Jul 18:e10306. doi: 10.1002/advs.202510306.
Since the properties of electron transfer and orbital interactions in oxygen electrocatalysts are highly spin-dependent, reaction kinetics and thermodynamics are very sensitive to the spin configuration. However, understanding the spin-related origin of catalytic activity in heterogeneous molecular electrocatalysts still remains challenging. Herein, a molecular-atomic coupled catalyst is constructed by integrating iron phthalocyanine (FePc) molecules with Fe-N atomic sites anchored on nitrogen-doped carbon nanotubes (FePc-Fe-NCNT). The strong electronic coupling between FePc and the Fe-N-containing carbon substrate triggers a transition of the Fe sites from a low-spin state to an intermediate-spin state. Additionally, the formation of σ* bonds between the electron-injected perpendicular d orbitals of intermediate-spin Fe and the 2p orbitals of adsorbed oxygen species suppresses site blocking and accelerates OH* desorption, thereby enhancing the reaction kinetics of the oxygen reduction reaction (ORR). The resulting catalyst exhibits exceptional ORR activity in alkaline media, reaching a half-wave potential of 0.89 V and negligible degradation after 10,000 cycles. Remarkably, the quasi-solid-state Zinc-air battery based on this prepared catalyst operates stably from -40 to 70 °C with minimal performance loss. This work reveals a spin-state manipulation strategy for the development of advanced molecular catalysts and provides new insights into the regulation of electronic structure for energy conversion technologies.
由于氧电催化剂中电子转移和轨道相互作用的性质高度依赖自旋，反应动力学和热力学对自旋构型非常敏感。然而，理解多相分子电催化剂中催化活性的自旋相关起源仍然具有挑战性。在此，通过将铁酞菁（FePc）分子与锚定在氮掺杂碳纳米管上的Fe-N原子位点（FePc-Fe-NCNT）整合，构建了一种分子-原子耦合催化剂。FePc与含Fe-N的碳基底之间的强电子耦合触发了Fe位点从低自旋态到中间自旋态的转变。此外，中间自旋Fe的垂直注入电子的d轨道与吸附氧物种的2p轨道之间形成σ键，抑制了位点阻塞并加速了OH脱附，从而提高了氧还原反应（ORR）的反应动力学。所得催化剂在碱性介质中表现出优异的ORR活性，半波电位达到0.89 V，经过10000次循环后降解可忽略不计。值得注意的是，基于这种制备的催化剂的准固态锌空气电池在-40至70°C下稳定运行，性能损失最小。这项工作揭示了一种用于开发先进分子催化剂的自旋态操纵策略，并为能量转换技术的电子结构调控提供了新的见解。
