2,3-diaminophenazine as a high-rate rechargeable aqueous zinc-ion batteries cathode

Organic materials are attracting extensive attention as promising cathodes for rechargeable aqueous zinc-ion batteries (ZIBs). However, most of them fail to implement the requirement of batteries with combined high-rate and long-cycle performance. Herein, we report a flexible organic molecule 2,3-diaminophenazine (DAP) which exhibits ultrahigh rate performance up to 500C and high capacity retention of 80% after 10,000 cycles at 100C (25.5 A g(-1)). Moreover, the Zn2+ storage mechanism in the DAP electrode is revealed by ex-situ characterization technologies and theoretical calculation, and the redox active centers C=N participate in the reversible electrochemical reaction process. Furthermore, electrochemical analyses show that surface-controlled electrochemical behavior contributes to the high-rate performance of DAP cathodes. Besides, its excellent long-cycle performance can be ascribed to the suppressed DAP dissolubility by using a modified glass fiber separator with carbon nanotubes (CNT) film. Our work provides useful insight into the design of high-rate and long-life ZIBs. (C) 2021 Elsevier Inc. All rights reserved.

Automated summary

This study introduces a flexible organic molecule, 2,3-diaminophenazine (DAP), with ultrahigh rate performance and high capacity retention in rechargeable aqueous zinc-ion batteries. The Zn2+ storage mechanism and surface-controlled electrochemical behavior of DAP cathodes are revealed through ex-situ characterization and theoretical calculation. The long-cycle performance of DAP is attributed to its suppressed dissolubility and the use of a modified separator with carbon nanotubes (CNT) film.