Synergistic Modulation of In-Situ Hybrid Interface Construction and pH Buffering Enabled Ultra-Stable Zinc Anode at High Current Density and Areal Capacity

In aqueous electrolytes, the uncontrollable interfacial evolution caused by a series of factors such as pH variation and unregulated Zn2+ diffusion would usually result in the rapid failure of metallic Zn anode. Considering the high correlation among various triggers that induce the anode deterioration, a synergistic modulation strategy based on electrolyte modification is developed. Benefitting from the unique pH buffer mechanism of the electrolyte additive and its capability to in situ construct a zincophilic solid interface, this synergistic effect can comprehensively manage the thermodynamic and kinetic properties of Zn anode by inhibiting the pH variation and parasitic side reactions, accelerating de-solvation of hydrated Zn2+, and regulating the diffusion behavior of Zn2+ to realize uniform Zn deposition. Thus, the modified Zn anode can achieve an impressive lifespan at ultra-high current density and areal capacity, operating stably for 609 and 209 hours at 20 mA cm-2, 20 mAh cm-2 and 40 mA cm-2, 20 mAh cm-2, respectively. Based on this exceptional performance, high loading Zn||NH4V4O10 batteries can achieve excellent cycle stability and rate performance. Compared with those previously reported single pH buffer strategies, the synergistic modulation concept is expected to provide a new approach for highly stable Zn anode in aqueous zinc-ion batteries. A synergistic modulation concept is developed by introducing taurine into electrolyte. In addition to buffering the pH of the electrolyte, the preferentially adsorbed taurine on the Zn surface reconstructs the electronic double layer (EDL) and subsequently builds an in situ hybrid interface to inhibit side reactions and regulate Zn deposition. This synergistic modulation strategy greatly enhances the performance of Zn anode and full batteries.+image