Abstract

A highly stable 3D π-conjugation covalent triazine-cored framework (Azo-CTF) with triazine as the electron-rich center bridged by azo redox-active linkers is proposed and prepared as cathode materials for improving both rate performance and cycle stability of LIBs, two critical issues addressed in organic electrodes. The synchronous and orderly introduction of electron-withdrawing units and redox active units in conjugated polymer framework can effectively tune electronic structure and redox potential of materials, contributing to the improvement of electrical and electrochemical behavior. Attributed to abundant redox azo sites, resilient and accessible pores network, and good intramolecular and interfacial electron transfer ability, Azo-CTF cathode shows a large and reversible capacity output of 205.6 mAh g−1, a ultralong cycle life (89.1% capacity retention after 5000 cycles), and a high power density of 4253 W kg−1 even at an energy density of 258 Wh kg−1, much better than many reported organic cathodes and even better than some commercial inorganic cathodes. In addition, in-situ Raman spectroscopy and theoretical calculations were done and further verified the redox process of azo active sites and the optimization of molecular orbital in covalent framework for better battery cathode, indicating the availability of molecular-level electronic structure tuning.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.