Robust ZnS interphase for stable Zn metal anode of high-performance aqueous secondary batteries

Abstract

Although Zn metal is an ideal anode candidate for aqueous batteries owing to its high theoretical capacity, lower cost, and safety, its service life and efficiency are damaged by severe hydrogen evolution reaction, self-corrosion, and dendrite growth. Herein, a thickness-controlled ZnS passivation layer was fabricated on the Zn metal surface to obtain Zn@ZnS electrode through oxidation-orientation sulfuration by the liquid- and vapor-phase hydrothermal processes. Benefiting from the chemical inertness of the ZnS interphase, the as-prepared Zn@ZnS electrode presents an excellent anti-corrosion and undesirable hydrogen evolution reaction. Meanwhile, the thickness-optimized ZnS layer with an unbalanced charge distribution represses dendrite growth by guiding Zn plating/stripping, leading to long service life. Consequently, the Zn@ZnS presented 300 cycles in the symmetric cells with a 42 mV overpotential, 200 cycles in half cells with a 78 mV overpotential, and superb rate performance in Zn parallel to NH4V4O10 full cells.