Building a seamless water-sieving MOF-based interphase for highly reversible Zn metal anodes

Aqueous zinc batteries are considered a promising candidate for large-scale energy storage because of their high safety and low cost. However, the rampant dendrite growth and deteriorative side reactions hinder the practical application of Zn metal anodes. Here, we propose a strategy to construct a seamless MOF-based interphase on the Zn surface via a vapor–solid reaction. The MOF interphase exhibits defect-free feature with high continuity, thus eliminating the undesired electrolyte diffusion along the intergranular voids of membranes with MOF particles. The pre-desolvation process initiated by the angstrom-sized pores and the homogenized Zn ion flux effectively suppress electrolyte side reactions and promotes uniform Zn deposition with preferred orientation along the (0 0 2) plane. A high Zn plating/stripping efficiency of 99.7% on average is achieved with stable cycling for 3200 cycles under the protection of the defect-free interphase.