摘要
Ladder-type conjugated polymers(LCPs)have attracted extensive attention in rechargeable lithium-ion batteries(LIBs)due to their inherent stability,poor solubility,tunable structure,and strongπ-πintermolecular interactions.Herein,we describe the synthesis of two heteroatom nitrogen/oxygen-rich LCPs(TABQ-NTCDA,named TNL,and TABQPMDA,named TPL)by the polycondensation reaction of tetromino-benzoquinone(TABQ)and aromatic dianhydride.Benefiting from the rigid backbone,the large conjugated skeleton and the heteroatom-driven superlithiation process in polycyclic aromatic systems,heteroatom nitrogen/oxygen-rich LCPs acting as organic anode materials for LIBs display high specific capacity and long-term cycle stability.In particular,TNL displays a high reversible capacity of 1063.5 mA h g^(-1) at 0.05 A g^(-1),good cyclic performance with a capacity retention of 75.2% after 1000 cycles at 1 A g^(-1),and excellent rate capability of 260.6 mA h g^(-1) even at 2 A g^(-1).In addition,the superlithiation storage mechanism was further confirmed by theoretical calculations,suggesting multiple active sites of C=O,C=N,and aromatic rings for lithium-ion storage.Furthermore,a full cell is also assembled by pairing a TNL anode with a LiCoO_(2) cathode,indicating the feasibility of practical application.
梯形共轭聚合物(LCPs)由于其固有的稳定性、较低的溶解性、可调的结构和强的π-π分子间相互作用,在可充电锂离子电池(LIBs)中引起了广泛关注.在此,我们通过四氨基苯醌和芳香族二酐之间的缩聚反应合成了两种富含杂原子氮/氧的LCPs(TNL和TPL).得益于多环芳烃体系中的刚性骨架,大共轭结构和杂原子驱动的超锂化过程,富氮/氧杂原子的LCPs作为LIBs的有机负极材料显示出高比容量和优异的长期循环稳定性.特别地,在0.05 A g^(-1)电流密度下,TNL展现了1063.5 mA h g^(-1)的高可逆比容量,良好的循环性能(在1 A g^(-1)电流密度下循环1000次后容量保持率为75.2%),以及优异的倍率性能(即使在2 A g^(-1)的电流密度下仍具有260.6 mA h g^(-1)比容量).此外,通过理论计算进一步证实了超锂化存储机制,表明C=O、C=N和芳香环的多个活性位点的锂离子存储机制.此外,还通过将TNL负极与LiCoO_(2)正极匹配来组装全电池,证明了其实际应用的可行性.
作者
Jie Yu
Xinyu Chen
Heng-guo Wang
Bo Gao
Donglai Han
Zhenjun Si
于杰;陈新宇;王恒国;高波;韩东来;司振君(Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education and Faculty of Chemistry,Northeast Normal University,Changchun 130024,China;School of Materials Science and Engineering,Changchun University of Science and Technology,Changchun 130022,China)
基金
supported by the National Natural Science Foundation of China(52172186)
the Science&Technology Department of Jilin Province(20210101116JC)
the Fundamental Research Funds for the Central Universities(2412021QD009)。
