In Situ Growth of S-doped ZnO Thin Film Enabling Dendrite-free Zinc Anode for High-performance Aqueous Zinc-ion Batteries

Aqueous rechargeable zinc-ion batteries (AZIBs) have gained extensive attentions due to their high volumetric capacity, low cost, and intrinsic safety. Nonetheless, their zinc metal anodes have been suffered from many issues, such as uncontrollable dendrite growth and undesired side reactions, which eventually degrade the capacity and cycle life. Herein, a thin sulfur-doped zinc oxide artificial interface film (≈200 nm) was in situ grown on zinc foil (ZnO:S@Zn) by a simple chemical bath deposition method. The density functional theory calculations revealed that the electronic conductivity of zinc oxide could be improved after sulfur doping. Characterization analyses and electrochemical measurements showed that this unique film could enhance the electrical conductivity of zinc anode inhibit the side reaction and induce Zn ²⁺ uniform deposition. As a result, the ZnO:S@Zn symmetric cell was stably cycled for 1700 h at 0.5 mA cm ⁻² with a stable voltage hysteresis of ~20 mV, and the full-cell pairing with MnO ₂ cathode exhibited an excellent reversible capacity of 297.46 mAh g ⁻¹ after 300 cycles. This work offers a simple and effective way to fabricate a stable Zn metal anode for high performance AZIBs.