Abstract

AbstractAqueous zinc‐ion batteries (ZIBs) are safe and economical for grid applications. However, current ZIBs have limitations in terms of inferior capacity and low output voltage, which are hampered by the electrolyte applicability of the Zn2+ hosts. In this study, we propose a novel organic cathode design strategy with a bifunctional potential region. This polymeric Zn2+ host combines the conjugated polyaniline backbone to tune the molecular surface pH and [Fe(CN)6]3−/4− redox couple for high output voltage and capacity. The polyaniline doped with ferricyanide (PAF) electrode exhibits two forms of charge storage in ZIBs: proton‐assisted Zn2+ doping below 1.2 V (mechanism I), and [Fe(CN)6]3−/4− redox pair above 1.8 V (mechanism II). Density functional theory calculations and in situ pH experiments demonstrated that the H+ doping process of mechanism I forms a localized pH regulation on the molecular chain surface, providing a favorable reaction environment for mechanism II. The Zn‐polymer battery delivered an outstanding discharge capacity (405.2 mAh g−1) and high output voltage (1.8 V) in the Zn(CF3SO3)2 electrolyte. This study provides a new route for enhancing the structural stability of electrodes and overcoming the electrolyte limitations of ferricyanide in weakly acidic electrolytes.

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.