LAUSR

In situ electro-polymerization of redox-active monomers has been proved to be a novel and facile strategy to prepare polymer electrodes with superior electrochemical performance. Monomer's molecular structure would have a profound impact on electro-polymerization behavior and thus electrochemical performance. However, this impact is poorly understood and has barely been investigated yet. Herein, three carbazole-based monomers, 9-phenylcarbazole (CB), 1,4-bis(carbazol-9-yl)benzene (DCB), and 2,6-bis(carbazol-9-yl)naphthalene (DCN) were applied to study the above issue systematically and achieve excellent long cycle performance. The monomers were rationally designed with different polymerizable sites and solubilities. It was found that monomer with increased polymerizable sites and decreased solubility brought about enhanced electrochemical performance. This is because poor solubility could enhance monomers' utilization for polymerization and more polymerizable sites could lead to stable cross-linked polymer network after electro-polymerization. DCN with four polymerizable sites and the poorest solubility displays the best electrochemical performance, which shows stable cycling up to 5000 cycles with high capacity retention of 76.2% (among the best cycle in the literatures). Our work for the first time reveals the relationship between monomer's structure and in situ electro-polymerization behavior. This work would shed light on the monomer's structure design/optimization for high-performance polymer electrodes prepared through in situ electro-polymerization method.