Zincophile Zn2+ Conductor Regulation by Ultrathin Nano MoO3 Coating for Dendrite‐Free Zn Anode

Abstract Aqueous battery with nonflammable and instinctive safe properties has received great attention. However, issues related to Zn anode such as side reactions and rampant dendrite growth hinder the long‐term circulation of AZMBs. Herein, an ultrathin(35 nm) MoO 3 coating is deposited on the Zn anode by means of vacuum vapor deposition for the first time. Due to the peculiar layer structure of MoO 3 , insertion of Zn 2+ in Zn x MoO 3 acts as Zn 2+ ion conductor, which regulates Zn 2+ deposition in an ordered manner. Additionally, the MoO 3 coating can also inhibit the hydrogen evolution and corrosion reactions at the interface. Therefore, both Zn//MoO 3 @Cu asymmetric battery and Zn symmetric battery cells manage to deliver satisfactory electrochemical performances. The symmetric cell assembled with MoO 3 @Zn shows a significant long cycle life of more than 1600 h at a current density of 2 mA cm −2 . Meanwhile, the MoO 3 @Zn//Cu asymmetric cell exhibits an ultrahigh Zn deposition/stripping efficiency of 99.82% after a stable cycling of 650 h at 2 mA cm −2 . This study proposes a concept of “zincophile Zn 2+ conductor regulation” to dictate Zn electrodeposition and broadens novel design of vacuum evaporation for nano MoO 3 modified Zn anodes.