Gao Hui, Tian Bingbing, Yang Haofan, Neale Alex R, Little Marc A, Sprick Reiner Sebastian, Hardwick Laurence J, Cooper Andrew I
Materials Innovation Factory and Department of Chemistry, University of Liverpool, 51 Oxford St, Liverpool, L7 3NY, UK.
International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, 518060, P. R. China.
ChemSusChem. 2020 Oct 21;13(20):5571-5579. doi: 10.1002/cssc.202001389. Epub 2020 Sep 2.
Conjugated polymers with electrochemically active redox groups are a promising class of positive electrode material for lithium-ion batteries. However, most polymers, such as polyimides, possess low intrinsic conductivity, which results in low utilization of redox-active sites during charge cycling and, consequently, poor electrochemical performance. Here, it was shown that this limitation can be overcome by synthesizing polyimide composites (PIX) with reduced graphene oxide (rGO) using an in situ polycondensation reaction. The polyimide composites showed increased charge-transfer performance and much larger specific capacities, with PI50, which contains 50 wt % of rGO, showing the largest specific capacity of 172 mAh g at 500 mA g . This corresponds to a high utilization of the redox active sites in the active polyimide (86 %), and this composite retained 80 % of its initial capacity (125 mAh g ) after 9000 cycles at 2000 mA g .
带有电化学活性氧化还原基团的共轭聚合物是一类很有前景的锂离子电池正极材料。然而，大多数聚合物，如聚酰亚胺，固有电导率较低，这导致在充电循环过程中氧化还原活性位点的利用率较低，因此电化学性能较差。在此，研究表明通过原位缩聚反应合成聚酰亚胺与还原氧化石墨烯（rGO）的复合材料（PIX）可以克服这一限制。聚酰亚胺复合材料表现出增强的电荷转移性能和大得多的比容量，其中含有50 wt% rGO的PI50在500 mA g下表现出最大比容量172 mAh g。这对应于活性聚酰亚胺中氧化还原活性位点的高利用率（86%），并且该复合材料在2000 mA g下循环9000次后保留了其初始容量（125 mAh g）的80%。
