Tailoring double-layer aromatic polymers with multi-active sites towards high performance aqueous Zn–organic batteries

Unlike most reported organic-inorganic cathodes, the organic-organic zinc hosts can fully exploit the flexible structures and various redox chemistries of the organics. Herein, nanoporous carbon electrodeposited with a wrapped poly(meta-aminophenol, 3-AP) sandwich layer and a good conductive poly(para-aminophenol, 4-AP) skin, designated as a C@poly(3-AP)/poly(4-AP) cathode, has been synthesized for the first time via a novel two-step electrodeposition method. The synergistic effect of the double-layer polymers endows the C@poly(3-AP)/poly(4-AP) cathode with an ultrahigh specific capacity, excellent rate performance and long-term lifespan that are superior to those of the pristine C@poly(3-AP) and C@poly(4-AP) electrodes. Also, the strong electron donor capabilities of the multiple active sites (CO and CN) in the hetero-structural organic cathode can exhibit symmetrical bending to host inserted Zn ions during the discharge process, which opens up new opportunities to construct advanced Zn-organic batteries.