Hydrophobic Organic–Inorganic Hybrid Surface Modification-Induced Uniform Zinc Deposition and Prohibited Side Reactions toward a Ultra-stable Zinc Anode

Abstract

Zinc-ion batteries (ZIBs) are ideal candidates for new ideal energy devices due to large theoretical capacity, scale production, and handleability. However, the problem of dendrite growth and side reactions originated from an uneven Zn plating/stripping process, and the direct contact of the Zn metal with the electrolyte reduces the cycle stability and lifetime of ZIBs. In this research, organic hydrophobic polyvinylidene fluoride and uniformly distributed nano-silicon particles (PVDF-Si) was constructed as a functional protection layer to promote the cycle stability of the Zn anode. Silicon nanoparticles can uniformly distribute electric field and Zn2+ flux on the Zn anode surface which can guide the uniform Zn deposition and avoid dendrite growth. The hydrophobic PVDF can reduce the free water content on the Zn anode surface, which significantly inhibits side reactions. With the coordinate inhibition of the PVDF-Si modification layer, the PVDF-Si@Zn anode displays dendrite-free Zn plating/stripping with a low overpotential of 38 mV after 3080 h in PVDF-Si@Zn||PVDF-Si@Zn batteries. Meanwhile, the PVDF-Si@Zn||V2O5 battery also achieved a high stability with a 79.38% capacity retention and nearly 100% of the coulomb efficiency after 500 cycles. The hydrophobic polymer–nanomaterial interface modification provides a new strategy for the protection of the Zn anode.