Multifunctional composite artificial interface layer endows highly stable Zn anodes

Aqueous zinc-ion batteries are regarded as energy storage devices with excellent development prospects, attributed to their high theoretical capacity, low cost, and favorable safety profile. Nevertheless, challenges such as severe dendrite and hydrogen evolution reactions on the zinc anode have significantly hindered the practical applications of aqueous zinc-ion battery devices. In this study, a Bi 2 S 3 -NC composite artificial interfacial layer was fabricated on the surface of the zinc electrode to modulate the thermodynamics and kinetics of zinc ion deposition/stripping reactions, thereby enabling a stable zinc anode. The experimental findings indicated that the hydrophobic Bi 2 S 3 -NC composite artificial interfacial layer could effectively suppress the occurrence of side reactions. Simultaneously, it regulated the desolvation ability of zinc ions and reaction kinetics, significantly reducing the nucleation energy barrier for zinc (the nucleation overpotential at a current density of 2 mA cm −2 decreased from 87.1 mV to 32.2 mV), thereby facilitating uniform zinc ion deposition. Ex-situ scanning electron microscopy (SEM) and in-situ optical microscopy characterizations further confirmed that the Bi 2 S 3 -NC protective layer could effectively inhibit the growth of zinc dendrites. Consequently, the modified Bi 2 S 3 -NC@Zn symmetric cell could cycle for more than 3200 h under the conditions of 2 mA cm −2 and 0.5 mAh cm −2 , and the overpotential was also significantly reduced (from 88.5 mV to 29.8 mV). Meanwhile, the Zn//Cu half-cell assembled with Bi 2 S 3 -NC@Zn could still maintain a coulombic efficiency of 99.69% after 270 cycles. Additionally, the full cell assembled with Bi 2 S 3 -NC@Zn and an Mn 2 V 2 O 7 cathode also demonstrated outstanding cycling stability (retained 115.7 mAh g −1 after 1400 cycles at 0.5 A g −1 ), far exceeding the 64.3 mAh g −1 of the bare Zn cell. This study proposes a simple and effective modification strategy for zinc anodes, providing a reference for the multi-dimensional improvement of zinc anode performance.