Selective Ion Transport Layer for Stable Aqueous Zinc‐Ion Batteries

Abstract The limited lifespan of aqueous zinc‐ion batteries (with vanadium‐oxide based cathodes) is constrained by practical applications due to corrosion accelerated by vanadium ions leaching from the cathode and uneven dendrite growth on the zinc metal anode. To address these issues, the difference in size between hydrated zinc ions (4.30 Å) in electrolyte and vanadium ions (8.34 Å) is considered. Uniformly coating the MOF‐801 nanoparticles (with a pore size of 6.0 Å) on the zinc foil formed a selective ion transport layer. The uniform zinc ion flux generated by the selective ion transport layer allows hydrated zinc ions to be transported evenly and promotes uniform zinc deposition, leading to a low overpotential (17.4 mV) and high cycle stability (1000 h) in the symmetric cell. Moreover, the selective ion transport layer, having pores smaller than vanadium ions, blocked vanadium ions …