Natural volcanic mud with de-solvation function as a protective layer for dendrite-free Zn anode

Despite a bright prospect because of intrinsic safety and low price, the commercialization of aqueous zinc-ion batteries (AZIBs) is hindered by serious issues including dendrite development, passivation and corrosion of Zn anodes. Herein, volcanic mud (VM) as a natural mineral is utilized as a protective layer of Zn anode (ZnVM@Zn). The nanoporous structure of VM can provide abundant channels for rapid migration of Zn 2+ ( t  = 0.92) and regulation of Zn 2+ flux, facilitating Zn uniform deposition. Furthermore, the ZnVM protective layer possesses low desolvation activation energy (44.56 kJ mol −1 ), effectively controlling the hydrated Zn-ions desolvation and thereby inhibiting water-induced corrosion and passivation of Zn anodes. Notably, nuclear magnetic resonance (NMR) also authenticates the desolvation effect of VM. With these characteristics, ZnVM@Zn||ZnVM@Zn symmetric cell achieves a lengthy circulation of over 1600 h at 0.5 mA cm −2 . ZnVM@Zn||MnO 2 full cell retains a capacity of 185.4 mAh g −1 after 700 circulations at 1 A g −1 , with 94.8% capacity-retention. This study offers novel insights into Zn anode protection in AZIBs.