Construction of an anti-anionic-depletion layer to mitigate the tip deposition effect for dendrite-free zinc anode

Rechargeable aqueous zinc-ion batteries have been plagued by the well-known problem of zinc dendrite formation. This issue mainly arises from the inherent depletion of anions in the vicinity of the zinc anode during deposition process, leading to a strong spatial electric field that influences Zn 2+ cations deposition and triggers dendrite growth. Herein, the anti-anionic-depletion strategy is proposed that involves anions anchored in the surface region of zinc anode to mitigate the adverse effects of the spatial electric field and inhibit dendrite growth. By theoretical calculations and experimental verification, layered double hydroxides (LDHs) materials were selected to immobilize SO 4 2- anions and construct a protective coating layer against anion depletion (anti-anionic-depletion layer). Furthermore, the deposition flux of Zn 2+ cations was also regulated by in-situ growing LDH nanosheets. Benefiting from these modifications, the in-situ grown ZnAl-LDH modified electrode (Zn@ZnAl) exhibits outstanding stability (5500 cycles at 40 mA cm −2 ), and shows negligible capacity degradation in both Zn-Mn full cells and zinc hybrid capacitors.