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

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||alpha-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.

Automated summary

Inspired by the interaction between zinc ions and amino acid chains in zinc finger proteins, a cost-effective and green glycine additive is introduced into aqueous electrolytes to stabilize the zinc anode. Experimental and theoretical results show that the glycine additive can reorganize the solvation sheaths of hydrated zinc ions and preferentially adsorb onto the zinc anode, effectively inhibiting dendrite growth and interfacial side reactions. The zinc anode exhibits a long lifespan of over 2000 hours and enhanced reversibility (98.8%) in the glycine-containing electrolyte. In addition, the assembled zinc||alpha-MnO2 full cells with glycine-modified electrolyte demonstrate a substantial capacity retention of 82.3% after 1000 cycles, indicating promising application prospects. This innovative bio-inspired design concept injects new vitality into the development of aqueous electrolytes.