Copper Nanoparticle-Modified Carbon Nanofiber for Seeded Zinc Deposition Enables Stable Zn Metal Anode

Challenges with the Zn anode for aqueous zinc ion batteries have hindered their practical applications, such as uncontrollable formation of the Zn dendrite and serious side reactions. Herein, we fabricate a flexible coating layer with porous and conductive carbon networks (Cu@CNFs) by a simple electrospinning method to construct a stable Zn anode. It can uniformly distribute the charge, regulate the Zn2+ flux, and stabilize the zinc anode. Moreover, the zincopilic Cu nanoparticles (CuNPs) in the coating layer act as nucleation seeds to facilitate the homogeneous deposition of Zn and inhibit its dendrite growth. Density functional theory calculations have further demonstrated the zincophilicity of the CuNPs seeds. As a result, the Cu@CNFs-Zn anode demonstrates a lower nucleation overpotential (58.3 mV at 5.0 mA cm–2) and a higher Coulombic efficiency compared with bare Zn and CNFs-Zn anodes. Remarkably, the Cu@CNFs-Zn anode can provide a stable cycle over 2200 h at 1.0 mA cm–2 with a capacity of 1.0 mAh cm–2. Moreover, the Cu@CNFs-Zn//V2O5 battery achieves a superior cyclability up to 1000 cycles at 0.5A g–1, which is attributed to the large surface areas of CNFs and the zincophilicity of the Cu@CNFs coating.