Cotton Cellulose Separator Regulated by Intermolecular Hydrogen Bonding for Effective Modulation of Zn2+ Transport and Deposition

Conventional glass fiber (GF) separators play a key role in aqueous zinc ion batteries (AZIBs). However, it is not only expensive but also lacks the ability to inhibit the growth of zinc dendrites, which ultimately leads to a decrease in battery capacity and even short circuits. Therefore, a low-cost functional separator (CF/CMC-NS) was developed by sodium sulfamate (NH2NaSO3) and carboxymethyl cellulose (CMC) based on cotton cellulose fiber (CF) separator. Theoretical calculations and experimental results show that the CF/CMC-NS separator has the ability to modulate ion transport, desolvate Zn2+, and provide a more homogeneous electric field to guide the uniform deposition of Zn2+. As a result, the Zn//Zn battery can be cycled for more than 500 h at a current density of 1 mA cm–2, and the Zn//V2O3 full battery exhibits a high-capacity retention of 96.9% and a high specific capacity of 361.5 mAh g–1 after 4000 cycles at 3.0 A g–1. The functionalized separator provides feasibility and technical support for its practical application in AZIBs by regulating ion transport and inhibiting the growth of zinc dendrites.