Integrating p-type phenazine into covalent triazine framework to achieve co-storage of cations and anions for quasi-solid-state dual-ion batteries

Abstract

Covalent triazine frameworks (CTFs) with bipolar features have garnered significant attentions in energy storage systems. Further, the integration of p-type active sites into CTFs is highly desirable. Herein, we integrated p-type phenazine into CTFs (PZ-CTF) to generate dual active centers with ion co-storage mechanism. Interestingly, the application of PZ-CTF as the cathode material in various battery systems was demonstrated. In lithium-based dual-ion batteries (LDIBs) with liquid electrolyte, PZ-CTF can show high discharge specific capacity (190.8 mAh g−1 at 200 mA g−1) and excellent rate capability (92.8 mAh g−1 at 3000 mA g−1). In quasi-solid-state LDIBs, PZ-CTF can possess high discharge specific capacity (187.5 mAh g−1 at 200 mA g−1) and long-cycle stability (108.2 mAh g−1 at 500 mA g−1 after 1000 cycles). In addition, in graphite-based DIBs (GDIBs), PZ-CTF also shows considerable electrochemical properties. Moreover, the continuous co-storage mechanism of PF6− and Li+ in PZ-CTF was confirmed by the theoretical calculations and spectral characterizations. This work opens a new avenue for integrating multi-polar organic electrode materials with multiple reaction mechanisms for the application of various battery systems.