Multielectron Redox-Bipolar Tetranitroporphyrin Macrocycle Cathode for High-Performance Zinc-Organic Batteries.

Abstract

Bipolar organics fuse the merits of n/p-type redox reactions for better Zn-organic batteries (ZOBs), but face the capacity plafond due to low density of active units and single-electron reactions. Here we report multielectron redox-bipolar tetranitroporphyrin (TNP) with quadruple two-electron-accepting n-type nitro motifs and dual-electron-donating p-type amine moieties towards high-capacity-voltage ZOBs. TNP cathode initiates high-kinetics, hybrid anion-cation 10e- charge storage involving four nitro sites coordinating with Zn2+ ions at low potential and two amine species coupling with SO4 2- ions at high potential. Consequently, Zn||TNP battery harvests high capacity (338 mAh g-1), boosted average voltage (1.08 V), and outstanding energy density (365 Wh kg-1 TNP). Moreover, the extended π-conjugated TNP macrocycle achieves anti-dissolution in electrolytes, prolonging the battery life to 50,000 cycles at 10 A g-1 with 71.6 % capacity retention. This work expands the chemical landscape of multielectron redox-bipolar organics for state-of-the-art ZOBs.