Ion Selective and Water Resistant Cellulose Nanofiber/MXene Membrane Enabled Cycling Zn Anode at High Currents

Abstract Aqueous rechargeable zinc ion batteries (ZIBs) are regarded as a promising candidates for next‐generation energy storage devices but strongly hindered by the limited utilization of the zinc metal anode (below 5%) due to the active water/anion corrosion. Herein, an ion selective and water‐resistant cellulose nanofiber (CNF)/MXene composite membrane has been developed through molecular sieving to restrict active water and anions from the electrode/electrolyte interface through dehydration of zinc ions, avoiding the water/anion‐induced corrosion/decomposition. In this way, the CNF/MXene@Zn anode exhibits significantly enhanced coulombic efficiency (99.5 % at 10 mA cm ‐2 ) and low voltage hysteresis. Moreover, coated with CNF/MXene composite membrane, zinc symmetric batteries can be operated at the extremely high current of 100 mA cm ‐2 and ultra‐high Zn utilization of 88.2% to achieve record‐high cumulative plating capacity of 12 Ah cm ‐2 . Furthermore, the full vanadium dioxide (VO 2 ) |CNF/MXene@Zn batteries exhibit a high capacity of 357 mAh g ‐1 at 2 A g ‐1 and retain 93.3% of the capacity after 500 cycles. Moreover, at negative/ positive capacity (N/P) ratio of 2.8, the CNF/MXene membrane coated zinc is able to stably cycle for 100 cycles, demonstrating the potential for high energy zinc battery. This designed CNF/MXene membrane enables ZIBs as viable energy storage devices for practical applications.