Weakly Solvating Effect Spawning Reliable Interfacial Chemistry for Aqueous Zn/Na Hybrid Batteries

摘要

The insufficient exploration of the interfacial chemistry of Zn anodes andelectrolytes in an aqueous environment restricts the application potential ofaqueous Zn batteries (AZBs). Herein, a durable anion-derived solid electrolyteinterface (SEI) with high ion conduction properties is constructed bydesigning an aqueous electrolyte with a weakly solvating effect to manipulatethe solvation structure of metal ions (Zn~（2+）/Na~+). The constructed SEI significantlyrestrains the dendrite formation and occurrence of adverse reactionson the surface of the Zn anode, endowing the Zn metal anode with highreversibility of deposition/stripping and ultra-long lifespan over 5000 h withan exceptional cumulative capacity of over 2.5 Ah cm~（?2）. Significantly, the formationmechanism of the SEI, which is realized by the weakly solvating effectto promote the coordination between anions and metal ions (Zn~（2+）/Na~+), andthe composition distribution of anion-derived inorganic-rich SEI, are clarifiedin detail. Furthermore, benefiting from the synergy of the elaborate SEIand the regulated electrolyte environment, the Zn//Prussian blue analogue(PBA) full battery can operate with a high voltage platform of 2.1 V and deliver99.3 capacity retention after 5000 cycles.