One-Pot preparation of microporous-polymer protected 3D porous Zn anode to enable advanced aqueous zinc batteries

Aqueous zinc-ion batteries hold a great promise for their low cost and high safety. However, Zn metal anodes suffer from the side reactions and Zn dendrites, which significantly reduce the utilization rate of Zn metal and affect the cycle performance of the battery. In this work, a 3D porous Zn anode coated by a microporous-polymer (DMBP-TB) layer is constructed in situ by iodine etching strategy. The 3D porous structure of Zn foil can manipulate Zn2+ flux and guide the uniform Zn deposition, which can avoid the growth of Zn dendrites. The protective layer serves as a physical barrier to reduce the free water components on the Zn foil surface, which can prevent detrimental side reactions. Benefiting from the synergistic effect of this specific structure, the symmetric battery has a long cycle lifespan of 3100 h at 0.5 mA cm−2 during Zn stripping/plating, and the asymmetric battery realizes a low nucleation-overpotential of 11.2 mV. Furthermore, the capacity retention rate of full battery is 97.7 % after 5000 cycles at 5 A g−1. This work provides a novel strategy for enhancing the stability and kinetics of aqueous zinc-ion batteries.