Decoupling Ion–Dipole Interactions via Competitive Coordination for Durable Dendrite-Free Zinc Metal Batteries

Abstract

Abstract The aqueous zinc metal batteries (AZMBs) are famous for high-safety and high-energy-density, but limited by severe challenges around the Helmholtz plane layer such as the strong ion–dipole interactions between Zn 2+ and H 2 O, resulting in slow desolvation processes and limited transport kinetics as well as corresponding higher barriers. To reconstruct the ion–dipole surroundings, the interface chemistry of employing a high permanent dipole moment of L -Carnosine ( L -CN) has been proposed, weakening the interactions between Zn 2+ and H 2 O to realize a crowded Zn 2+ -conductive structure, accelerating the desolvation kinetics. As revealed, the strong affinity between L -CN and Zn 2+ enables the L -CN molecules to repulse H 2 O, reconfiguring the inner Helmholtz plane layer, thereby inhibiting the active water molecular to form hydrogen evolution reactions. Consequently, the Zn//Zn symmetric cells with Helmholtz plane modulation achieve a long lifespan up to 7000 h, a high Coulombic efficiency of 99.72%, and a high stabilization at high depth of discharge (85.4%). The assembled Zn//V 2 O 5− x full cell with optimal electrolyte delivers the capacity of 289 mAh g −1 after 500 cycles at 1 A g −1 under an N/P ratio of 3.98. Impressively, the large-scale pouch cell with optimal electrolyte stabilizes for 200 cycles, offering the bright future of reconstructing Helmholtz plane for achieving high-performance AZMBs.