Host-guest supramolecular interaction behavior at the interface between anode and electrolyte for long life Zn anode

Abstract

The hydrogen evolution reaction (HER) and dendrite growth associated with Zn anode have become the main bottlenecks for the further development of zinc ion batteries (ZIBs). In this work, the electrochemical activity of H3O+ is inhibited by the supramolecular host–guest complex composed of H3O+ as guest and 18-crown-6 as host. The even Zn plating is induced by the host–guest complex electrostatic shielding layer on Zn anode, as detected by in-situ optical microscopy. The lamellar Zn is plated which profits from the improved Zn plating behavior. Density functional theory (DFT) calculation presents the stable structure of complex. The less produced H2 content is monitored online by a mass spectrometer during Zn plating/stripping, which indicates HER can be hampered by the host–guest behavior. Thus, the ZIBs with long life and high Coulombic efficiency are achieved via introducing 18-crown-6. The proposed host–guest supramolecular interaction is expected to facilitate the furthermore development of Zn batteries.