Chen Qi, Kang Hongwei, Gao Yuchen, Zhang Longhai, Wang Rui, Zhang Shilin, Zhou Tengfei, Li Hongbao, Mao Jianfeng, Zhang Chaofeng, Guo Zaiping
Institutes of Physical Science and Information Technology, School of Materials Science and Engineering, Leibniz International Joint Research Center of Materials Sciences of Anhui Province, Anhui Province Key Laboratory of Environment-Friendly Polymer Materials, Key Laboratory of Structure and Functional Regulation of Hybrid Material (Ministry of Education), Anhui University, Hefei 230601, China.
School of Chemistry and Materials Engineering, Anhui Provincial Key Laboratory for Degradation and Monitoring of Pollution of the Environment, Fuyang Normal University, Fuyang 236037, China.
ACS Appl Mater Interfaces. 2024 Sep 18;16(37):48736-48747. doi: 10.1021/acsami.3c11111. Epub 2023 Oct 24.
Organic compounds exhibit great potential as sustainable, tailorable, and environmentally friendly electrode materials for rechargeable batteries. However, the intrinsic defects of organic electrodes, including solubility, low ionic conductivity, and restricted electroactivity sites, will inevitably decrease the cycling life and capacity. We herein designed and prepared nanostructured porous polymers (NPP) with a simple one-pot method to overcome the above defects. Theoretical calculations and experimental results demonstrate that the as-synthesized NPP exhibited low volume expansion, molecular-structural distortion, and a gradual function activation process during cycling, thus exhibiting superior, high, and durable lithium storage. The gradual molecular distortion during the lithium storage processes provides more redox-active sites for Li storage, increasing the Li-storage capacity. Ex situ spectrum studies reveal the redox reaction mechanism of Li storage and demonstrate a gradual activation process during the repeated charging/discharging until the full storage of 18 Li ions is achieved. Additionally, a real-time observation on the NPP anode by in situ transmission electron microscope reveals a slight volume expansion during the repeating lithiation and delithiation processes, ensuring its structural integrity during cycling. This quantitative work for high-durability lithium storage could be of immediate benefit for designing organic electrode materials.
有机化合物作为可充电电池可持续、可定制且环境友好的电极材料展现出巨大潜力。然而，有机电极的固有缺陷，包括溶解性、低离子电导率和有限的电活性位点，将不可避免地降低循环寿命和容量。我们在此采用简单的一锅法设计并制备了纳米结构多孔聚合物（NPP）以克服上述缺陷。理论计算和实验结果表明，所合成的NPP在循环过程中表现出低体积膨胀、分子结构畸变以及逐渐的功能激活过程，从而展现出优异、高且持久的锂存储性能。锂存储过程中的逐渐分子畸变提供了更多用于锂存储的氧化还原活性位点，提高了锂存储容量。非原位光谱研究揭示了锂存储的氧化还原反应机制，并证明了在重复充放电直至实现18个锂离子的完全存储过程中的逐渐激活过程。此外，通过原位透射电子显微镜对NPP阳极的实时观察揭示了在重复锂化和脱锂过程中的轻微体积膨胀，确保了其在循环过程中的结构完整性。这项关于高耐久性锂存储的定量工作对于设计有机电极材料可能具有直接益处。
