Electrolyte Regulation of Bio‐Inspired Zincophilic Additive toward High‐Performance Dendrite‐Free Aqueous Zinc‐Ion Batteries

Abstract

Aqueous zinc‐ion batteries hold attractive potential for large‐scale energy storage devices owing to their prominent electrochemical performance and high security. Nevertheless, the applications of aqueous electrolytes have generated various challenges, including uncontrolled dendrite growth and parasitic reactions, thereby deteriorating the Zn anode's stability. Herein, inspired by the superior affinity between Zn2+ and amino acid chains in the zinc finger protein, a cost‐effective and green glycine additive is incorporated into aqueous electrolytes to stabilize the Zn anode. As confirmed by experimental characterizations and theoretical calculations, the glycine additives can not only reorganize the solvation sheaths of hydrated Zn2+ via partial substitution of coordinated H2O but also preferentially adsorb onto the Zn anode, thereby significantly restraining dendrite growth and interfacial side reactions. Accordingly, the Zn anode could realize a long lifespan of over 2000 h and enhanced reversibility (98.8%) in the glycine‐containing electrolyte. Furthermore, the assembled Zn||α‐MnO2 full cells with glycine‐modified electrolyte also delivers substantial capacity retention (82.3% after 1000 cycles at 2 A g‐1), showing promising application prospects. This innovative bio‐inspired design concept would inject new vitality into the development of aqueous electrolytes.

Reunderstanding aqueous Zn electrochemistry from interfacial specific adsorption of solvation structures

“…In particular, a significant negative shift in the potential of zero charge (PZC) is detected in the sulfate system. 49,50 The results can be ascribed to the strong specific adsorption of SO 4 2− at the interface. Likewise, with the help of the optimized adsorption model (Fig.…”

“…Furthermore, more charges are adsorbed at the interface, which may form a higher interfacial capacitance. 49 So the specific adsorption behavior on the zinc electrode surface is also studied by differential capacitance. As shown in Fig.…”

“…In particular, a significant negative shift in the potential of zero charge (PZC) is detected in the sulfate system. 49,50 The results can be ascribed to the strong specific adsorption of SO ), indicating that the former has feeble specific adsorption, which is not conducive to zinc deposition based on the c1 effect. 31 Thus, this attenuated specific adsorption of CF 3 SO 3 À anion in IHP could lead to Zn 2+ -leanness in the outer Helmholtz plane (OHP) rather than Zn 2+ -enrichment for the strong specific adsorption of SO 4 2À anions, which could retard the zinc deposition kinetics (Fig.…”

Self-assembled multilayers direct a buffer interphase for long-life aqueous zinc-ion batteries

“…Drawing inspiration from the superior affinity of amino acids for Zn, as well as their cost-effectiveness and environmental sustainability, 26,27 we selected well-used l -cysteine ( l -cys) 28,29 as a molecular building block to construct a self-assembled multilayer (SAM). SAM-Zn with polar groups provides strong dipole moments and conjugation with spatial topology structures.…”

“…Therefore, under the premise of maintaining adhesion stability and minimizing the sacrifice of energy density, a potential solution is the ingenious design of self-assembled molecular layers based on specific functional groups to achieve stable interface functionality during ultralong cycling. 25 Drawing inspiration from the superior affinity of amino acids for Zn, as well as their cost-effectiveness and environmental sustainability, 26,27 we selected well-used L-cysteine (L-cys) 28,29 as a molecular building block to construct a self-assembled multilayer (SAM). SAM-Zn with polar groups provides strong dipole moments and conjugation with spatial topology structures.…”