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 (CO and CN) 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.