A Nanocluster Colloidal Electrolyte Enables Highly Stable and Reversible Zinc Anodes

Aqueous zinc-ion batteries represent a favorable technology for stationary energy storage systems owing to their safety, reliability, and cost-effectiveness. However, Zn anodes suffer uncontrollable dendrite formation and harmful side reactions that lead to a short lifespan. Herein, we demonstrate a nanocluster colloidal electrolyte strategy for stabilizing the zinc anodes. A copper nanocluster (CuNC) is screened out to validate the efficient suppression of messy dendrites and side reactions. A CuNC could resurface a zincophilic and protective interlayer for interfacially steering uniform Zn stripping/plating and mitigating corrosion/hydrogen evolution reactions. Impressively, the colloidal electrolyte enables zinc anodes to show a high Coulombic efficiency of 99.8% over 2100 cycles and extended lifespans of 2200 and 1300 h under 0.5 and 5 mA cm^-2, respectively. A full cell based on the modified electrolyte exhibits significantly improved cycling durability for more than 15 000 cycles. This work will aid in the design of nanocluser colloidal electrolytes with respect to stable zinc chemistry and beyond.