Molecular engineering of nitrile-based additives by oxygen incorporation for a highly stable Zn anode

Abstract

Rechargeable aqueous zinc-ion batteries (AZIBs) face significant challenges toward commercialization, primarily attributed to dendritic zinc growth and H₂O-induced parasitic reactions. Herein, we propose a molecular engineering strategy based on oxygen incorporation into nitrile as a multifunctional additive to stabilize Zn anodes. By introducing ether oxygen atoms into the nitrile framework, 3-(2-methoxyethoxy)propionitrile (MEON) is constructed to regulate interfacial chemistry and the hydrogen-bond network. The incorporated oxygen atoms endow MEON with strong polarity and multi-site interaction capability, enabling parallel adsorption on the Zn surface and suppressing hydrogen evolution and corrosion. Meanwhile, MEON acts as an efficient hydrogen-bond acceptor that reconstructs the hydrogen-bond network and reduces water activity. This synergistic effect promotes the formation of a stable organic–inorganic hybrid interphase that effectively inhibits dendrite growth. As a result, Zn||Zn cells deliver highly stable plating/stripping for over 2400 h at 1 mA cm⁻² and 1 mAh cm⁻², and Zn||MnO₂ cells exhibit improved capacity and cycling stability. This work demonstrates that oxygen incorporation-enabled molecular design provides a powerful strategy for constructing multifunctional electrolyte additives and stabilizing Zn metal anodes for AZIBs.