Silane cooperation with Ce (III) to construct efficient protective layer and induce uniform deposition of Zn2+ for ultra-stable Zn anode

Abstract

Aqueous Zn ion batteries (ZIBs) are gaining interest in large-scale energy storage systems due to their intrinsic safety, low cost and sustainability. Unfortunately, water-induced side reactions and dendrite growth on Zn anode have severely hampered the further development. Herein, 3-aminopropyltrimethoxysilane (KH-540) was employed as an electrolyte additive to construct an organic-inorganic solid/electrolyte interface (SEI) layer composed of Zn hydroxy sulfate and polysiloxane to alleviate the side reactions and inhibit dendrite growth. Moreover, Ce3+ was simultaneously introduced to shield the protuberances on the surface of Zn anode, thus effectively decreased the “tip effect”. Due to the synergistic effect of the dual additives, uniform Zn deposition was achieved and the cycling stability of Zn anode was significantly improved. As a result, the Zn||Zn symmetric battery exhibits a long cycle life of 5000 h at the current density of 1.0 mA cm-2 with the areal capacity of 1.0 mAh cm-2, as well as high coulombic efficiency of nearly 100%. The Zn||V2O5 full cell delivers high specific capacity of 239.46 mAh g-1 even after 1000 cycles.