Huang Changmiao, Li Hui, Teng Zixuan, Luo Yushu, Chen Wanyu
School of Materials Science and Engineering, Wuhan University of Technology Wuhan 430070 China
RSC Adv. 2024 May 13;14(22):15337-15346. doi: 10.1039/d4ra02200a. eCollection 2024 May 10.
Zinc-ion batteries are promising candidates for large-scale energy storage, and gel polymer electrolytes (GPEs) play an important role in zinc-ion battery applications. Metal-organic frameworks (MOFs) are characterized by large specific surface areas and ordered pores. This highly ordered microporous structure provides a continuous transport channel for ions, thus realizing the high-speed transmission of ions. In this paper, an MOF-modified dendrite-free GPE was designed. The incorporation of MOF particles not only reduces the crystallinity of the polymer, increases the motility of the molecular chains, and facilitates the transfer of Zn, but also attracts anions to reduce polarization during electrochemical reactions. It was shown that this MOF-modified gel polymer electrolyte has a higher ionic conductivity compared to other PVDF-based polymer electrolytes (approximate range of 2 × 10 to 3 × 10 S cm), with a very high conductivity (1.63 mS cm) even at -20 °C. The Zn/Zn symmetric cell could maintain operation for more than 3600 h at a current density of 1 mA cm, and SEM showed that the MOF-modified gel electrolyte had uniform Zn deposition.
锌离子电池是大规模储能领域颇具潜力的候选者，而凝胶聚合物电解质（GPEs）在锌离子电池应用中发挥着重要作用。金属有机框架（MOFs）具有大比表面积和有序孔道的特点。这种高度有序的微孔结构为离子提供了连续的传输通道，从而实现离子的高速传输。本文设计了一种MOF改性的无枝晶GPE。MOF颗粒的掺入不仅降低了聚合物的结晶度，增加了分子链的活动性，促进了Zn的转移，还吸引阴离子以减少电化学反应过程中的极化。结果表明，与其他基于聚偏氟乙烯的聚合物电解质相比，这种MOF改性的凝胶聚合物电解质具有更高的离子电导率（近似范围为2×10至3×10 S cm），即使在-20°C时也具有非常高的电导率（1.63 mS cm）。Zn/Zn对称电池在1 mA cm的电流密度下可保持运行超过3600小时，扫描电子显微镜（SEM）显示MOF改性的凝胶电解质具有均匀的锌沉积。
