Improving performance of aqueous Zn//MnO2 battery using hydrogen-substituted graphdiyne as artificial coating

Metallic Zn anode faces common problems of dendrite growth, severe hydrogen evolution reaction (HER), and self-corrosion in the aqueous environment of zinc-ion batteries (ZIBs), which eventually short circuits the battery and causes significant capacity loss. Among the various strategies to prevent the issues of ZIBs, the approach of in-situ synthesis of a conductive artificial layer is at the forefront. Herein, constructing a hydrogen-substituted graphdiyne (HGDY) interface using the modified Eglinton method on the Zn surface is proposed, which is highly feasible and can be attempted at ambient conditions. This strategy prolongs the lifespan of the symmetric cell to >1000 h, much higher than without protection (210 h). During practical use, the fabricated ZIB delivers a superior capacity of ∼295 mAh g⁻¹ at 0.2 A g⁻¹ and improved cycling performance due to the extensive π-conjugated system, hierarchical porous structure, and large surface area. These excellent electrochemical properties suggest that the H-substituted graphdiyne with porous carbon interface can be scaled up and used as a potential artificial coating on the surface of anode material for high-performance Zinc ion batteries.