Direct Ink Printing for Flexible Zinc-Ion-Hybrid Micro-Supercapacitors Based on Hierarchical Porous Carbon as Cathode

Flexible artificial intelligence and rechargeable electronic devices have been the research hotpot due to the status quo of the energy crisis. However, the existing energy storage devices suffering from undesirable electrochemical performance, poor flexibility, and toxicity, have unsatisfactory practical application prospect. Owing to its unique stability, normal electrodes in energy storage equipment are built out of carbon-based materials. Recently, zinc hybrid supercapacitors have attracted a lot of attention. Herein, a high-performance zinc-ion hybrid micro-supercapacitor is successfully constructed using hierarchical honeymoon-like porous carbon frameworks as cathode by direct ink printing method. Due to the bivalent feature of zinc and electric double layered capacitive characteristic of the porous carbon, the optimized device possesses excellent electrochemical performance of excellent specific capacity of 189.06 mA h g(-1) at a current density of 1 mA cm(-2), high energy density of76.38 Wh kg(-1), power density of 499.94 W kg(-1) and superior capacity retention of 95.71 % at 10 mA cm(-2) after 1000 cycles. Through direct ink printing, the as-assembled zinc hybrid micro-supercapacitors based on flexible substrate exhibit outstanding flexibility with controllable active material mass loading.