Simultaneous manipulation of electron/Zn2+ion flux and desolvation effect enabled by in-situ built ultra-thin oxide-based artificial interphase for controlled deposition of zinc metal anodes

Abstract

Aqueous Zn metal batteries (AZMBs) are promising candidates for large-scale energy storage systems, but metallic Zn anodes persistently suffer from severe dendrite proliferation, causing a steep decline in battery lifetime and limiting practical applications. In this study, an ultrathin, sturdy artificial solid electrolyte inter -phase (ASEI), mainly composed of interconnected ZnO nanoparticles (ZnO-rich ASEI), is fabricated on the Zn surface by a novel in-situ ZnO nucleation and growth strategy to alleviate this dendrite problem. The uniformly and densely coated ZnO-rich ASEI enabled simultaneous manipulation of electron/Zn2+ flux and the desolvation effect on the Zn surface, which minimized the occurrence of dendrites and side-reactions and improved Zn deposition kinetics. The ZnO-rich ASEI effectively guided preferential Zn growth along the Zn(002) plane with thorough 2D atom diffusion confinement for even Zn plating. Consequently, despite the thin thickness of ZnO-rich ASEI, the symmetric cell achieved an outstanding cyclability (over 550 h) even under harsher condition (20 mA cm-2, 10 mAh cm-2) than a realistic condition (5 mAh cm-2) of practical AZMBs. Moreover, the voltage hysteresis reduction effect stemming from ZnO-rich ASEI is excellent compared to state-of-the-art research related to ASEI@Zn. The superiority of ZnO-rich ASEI@Zn was also verified in a Zn/MnO2 full-cell test, exhibiting superb long-term cyclability. This study provides a new direction for future research on stable Zn anodes using ASEI fabrication.