Aqueous zinc batteries using N-containing organic cathodes with Zn2+ and H+ Co-uptake

Abstract

Aqueous zinc batteries are considered as one of the most promising energy storage systems for large-scale energy storage and wearable electronics, owing to their low cost and intrinsic safety. However, developing high-performance cathode materials with environmentally friendly is still an important task. Here, we demonstrate that two N-containing organic compounds, hexamethoxy hexaazatrinaphthylene (HMHATN) and hexaazatrinaphthylene (HATN), used as cathodes can exhibit high capacity with fast kinetics. Thus, the Zn//HMHATN and Zn//HATN full batteries display the high energy density of 160 and 221.6 W h Kg−1, respectively, and long-term cycling stability. Electrochemical analysis, density functional theory calculation and ex situ analysis identify that the organic cathodes involve uptake and removal of Zn2+ and H+ in the discharging-charging process. Furthermore, the flexible aqueous Zn//HMHATN and Zn//HATN batteries fabricated also have high capacity, long-term cycling life and impressive energy density, displaying its application prospect in wearable electronics.