Ohmic-contact engineering of Cu₂S-protected zinc anodes for dendrite-free aqueous zinc metal batteries

Aqueous zinc metal batteries are promising candidates for large-scale energy storage, yet their practical application is severely limited by dendrite growth, hydrogen evolution and corrosion at the Zn anodes. Herein, we report a Cu₂S-mediated interfacial engineering strategy to stabilize Zn anodes through coupled electronic-field regulation and Zn²⁺ deposition modulation. The compact Cu₂S layer enhances the hydrophobicity of the Zn surface, suppresses direct contact between Zn and active water molecules, and markedly reduces corrosion and hydrogen evolution. More importantly, the favorable work-function difference between Cu₂S and Zn enables the formation of a low-resistance ohmic-contact interface, which promotes interfacial electron redistribution, homogenizes the surface electric field, and mitigates local charge accumulation. In addition, the zincophilic Cu₂S layer exhibits strong Zn²⁺ adsorption and a high Zn²⁺ transference number, facilitating ion transport, lowering the nucleation barrier, and guiding preferential Zn deposition along the Zn (002) plane. As a result, symmetric cells deliver stable cycling for 1400 h at 5 mA cm⁻² and 2.5 mAh cm⁻², while full cells paired with V₂O₅ and MnO₂ cathodes exhibit long-term stability over 2000 cycles at 1 A g⁻¹. This work highlights ohmic-contact engineering as an effective physical-field regulation strategy for constructing dendrite-resistant and corrosion-suppressed Zn metal anodes.