Polyaniline functionalized separator as synergistic medium for aqueous zinc-ion batteries

Aqueous zinc-ion batteries (AZIBs) have received increasing attention as a promising energy storage device. However, it was rarely reported that the separators as a synergistic medium stabilize the cathode and anode materials. Herein, a polyaniline functionalized glass fiber separator (PANI-GF) was synthesized in situ. The porous structure of PANI effectively regulated the flux of zinc ions inside the separator and its deposition behavior through ion confinement. The abundant N-containing functional groups can adsorb water molecules and effectively reduce harmful side reactions. Moreover, the PANI-GF separator adjusted pH to inhibit dissolution of the cathode by protonation. Importantly, based on the synergistic separator, the Zn-MnO₂ full cell exhibited more than twice discharge capacity compared to the conventional cell after 1000 cycles at 2 A g^-1. This study provided in-depth insight into the design of convenient, reliable, cost-effective, and synergistic separators for AZIBs.