A COF-Like N-Rich Conjugated Microporous Polytriphenylamine Cathode with Pseudocapacitive Anion Storage Behavior for High-Energy Aqueous Zinc Dual-Ion Batteries.

Abstract

Conducting polymers with good electron conductivity and rich redox functional groups are promising cathode candidates for constructing high-energy aqueous zinc batteries. However, the glaring flaw of active-site underutilization impairs their electrochemical performance. Herein, we report a poriferous polytriphenylamine conjugated microporous polymer (CMP) cathode capable of accommodating Cl^- anions in a pseudocapative-dominated manner for energy storage. Its specific 3D, covalent-organic-framework-like conjugated network ensures high accessibility efficacy of N active sites (up to 83.2% at 0.5 A g^-1 ) and distinct physicochemical stability (87.6% capacity retention after 1000 cycles) during repeated charging/discharging courses. Such a robust CMP electrode also leads to a zinc dual-ion battery device with a high energy density of 236 W h kg^-1 and a maximum power density of 6.8 kW kg^-1 , substantially surpassing most recently reported organic-based zinc batteries. This study paves the way for the rational design of advanced CMP-based organic cathodes for high-energy devices.