In Situ Growth of 2D Metal–Organic Framework Ion Sieve Interphase for Reversible Zinc Anodes

Zinc metal anodes are gaining popularity in aqueous electrochemical energy storage systems for their high safety, cost-effectiveness, and high capacity. However, the service life of zinc metal anodes is severely constrained by critical challenges, including dendrites, water-induced hydrogen evolution, and passivation. In this study, a protective two-dimensional metal–organic framework interphase is in situ constructed on the zinc anode surface with a novel gel vapor deposition method. The ultrathin interphase layer (~1 μm) is made of layer-stacking 2D nanosheets with angstrom-level pores of around 2.1 Å, which serves as an ion sieve to reject large solvent–ion pairs while homogenizes the transport of partially desolvated zinc ions, contributing to a uniform and highly reversible zinc deposition. With the shielding of the interphase layer, an ultra-stable zinc plating/stripping is achieved in symmetric cells with cycling over 1000 h at 0.5 mA cm⁻² and ~700 h at 1 mA cm⁻², far exceeding that of the bare zinc anodes (250 and 70 h). Furthermore, as a proof-of-concept demonstration, the full cell paired with MnO₂ cathode demonstrates improved rate performances and stable cycling (1200 cycles at 1 A g⁻¹). This work provides fresh insights into interphase design to promote the performance of zinc metal anodes.