Corrosion-resistant organic-inorganic hybrid interphase integrated with nitrile coordination enables highly stable zinc metal anodes

Aqueous zinc metal batteries are promising for large-scale energy storage, but nonuniform Zn 2+ transport, dendritic deposition, corrosion, hydrogen evolution, and insulating by-products undermine Zn reversibility. Here, a functionally stratified zinc oxalate/ polyacrylonitrile–zinc trifluoromethanesulfonate(PAN–Zn(OTf) 2 ) dual interphase is constructed on Zn by oxalic-acid-induced in situ conversion followed by solution coating(denoted as CNS@Zn). The outer PAN–Zn(OTf) 2 layer improves electrolyte wettability and ion-conduction capability, while nitrile–Zn 2+ coordination modifies the local coordination environment of Zn 2+ and facilitates more homogeneous interfacial Zn 2+ transport. The in situ formed zinc oxalate inner interphase limits direct exposure of active Zn to the aqueous electrolyte, suppressing corrosion, hydrogen evolution, and parasitic by-product formation. This sequential regulation from ion delivery to interfacial deposition reduces the apparent interfacial activation energy from 76.36 to 41.85 kJ mol −1 and promotes uniform, compact Zn deposition. Consequently, the CNS@Zn||NVO full cell retains approximately 140 mAh g −1 after 1930 cycles at 5 A g −1 , while the CNS@Zn||NVO pouch cell maintains approximately 250 mAh g −1 over 120 cycles at 1 A g −1 . This work establishes a hierarchical interface design coupling ion-transport regulation with corrosion protection for durable aqueous Zn metal anodes. Download: Download high-res image (130KB) Download: Download full-size image