Wang Liang-Yu, Ma Chao, Yang Jia-Ning, Wang Kai-Xue, Chen Jie-Sheng
Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, Shanghai, 200240, China.
College of Smart Energy, Shanghai Jiao Tong University, Shanghai, 200240, China.
Angew Chem Int Ed Engl. 2025 Jan 2;64(1):e202413452. doi: 10.1002/anie.202413452. Epub 2024 Oct 17.
Organic-metal coordination materials with rich structural diversity are considered as promising electrode materials for rechargeable sodium-ion batteries. However, the electrochemical performance can be constrained by the limited number of active sites and structural instability under the discharge/charge process. Herein, organometallic polymer microspheres (Fe-PDA-220) with a unique d-π conjugated structure was designed and successfully constructed through a simple synchronous polymerization and coordination reactions. Polymerization of phenylenediamine was initiated by Fe and Fe ions generated synchronously during the polymerization integrated with poly-aminoquinone chains to form Fe-CN active centers. Used as electrode materials for sodium-ion batteries, the distinctive Fe-C bond significantly boosts the structural stability, and the π-d conjugation system could facilitate electron transfer. A high reversible capacity of 345 mAh g was delivered at 0.1 A g and a capacity of 106 mAh g was maintained even after discharged/charged at 1.0 A g for 5000 cycles, outperforming most reported coordination materials. Spectroscopic and electronic analyses revealed that a two-electron reaction occurred per active unit, accompanied by the reversible redox evolution of the C=N groups and Fe ions during the sodiation/desodiation. This work provides a promising and efficient strategy for boosting the electrochemical performance of organic electrode materials by the design of organometallic polymers.
具有丰富结构多样性的有机金属配位材料被认为是有前景的可充电钠离子电池电极材料。然而，其电化学性能可能会受到活性位点数量有限以及充放电过程中结构不稳定性的限制。在此，通过简单的同步聚合和配位反应设计并成功构建了具有独特d-π共轭结构的有机金属聚合物微球（Fe-PDA-220）。在聚合过程中，铁和铁离子同步产生，引发苯二胺的聚合，并与聚氨基醌链整合形成Fe-CN活性中心。作为钠离子电池的电极材料，独特的Fe-C键显著提高了结构稳定性，π-d共轭体系有助于电子转移。在0.1 A g的电流密度下，其可逆容量高达345 mAh g，即使在1.0 A g的电流密度下充放电5000次后，仍能保持106 mAh g的容量，优于大多数已报道的配位材料。光谱和电子分析表明，每个活性单元发生双电子反应，在钠化/脱钠过程中伴随着C=N基团和铁离子的可逆氧化还原演变。这项工作通过设计有机金属聚合物，为提高有机电极材料的电化学性能提供了一种有前景且高效的策略。
