Design and construction of poly(benzoquinone-diamine)/Ti3C2TX hybrid electrode toward advanced aqueous zinc-ion batteries

Owing to the virtues of low cost, high security, and flexible structure design, zinc-ion batteries (ZIBs) have arisen widespread focus as a rising star in the application of energy-storage devises. Unfortunately, the further advancement of aqueous ZIBs is restricted by the unsatisfactory conduction of electron and structural instability of electrodes. Herein, a new organic-inorganic hybrid material, poly(benzoquinone-diamine)/Ti3C2TX (PBD/Ti3C2TX), has been conceived and fabricated as a cathode of ZIBs for the first time. The abundant CC and CO groups of PBD resulted in improved charge transfer and insolubility, which attributed to various hydrogen bonds and π-π packing interactions. Meanwhile, the Ti3C2TX can improve the electronic conductivity of the hybrid electrode effectively. In addition, the rich functional groups on the surface of Ti3C2TX are propitious to form a tight junction between PBD and Ti3C2TX (such as hydrogen bonds), which is conducive to strengthening the stability of electrode structure. With the synergistic effort of these measures, the PBD/Ti3C2TX composite delivers excellent long-term cycle stability (90 mAh g−1 at 1 A g−1 after 2000 cycles) with high-capacity retention of 78%.