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

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) MoO₃ coating is deposited on the Zn anode by means of vacuum vapor deposition for the first time. Due to the peculiar layer structure of MoO₃, insertion of Zn²⁺ in Zn_xMoO₃ acts as Zn²⁺ ion conductor, which regulates Zn²⁺ deposition in an ordered manner. Additionally, the MoO₃ coating can also inhibit the hydrogen evolution and corrosion reactions at the interface. Therefore, both Zn//MoO₃@Cu asymmetric battery and Zn symmetric battery cells manage to deliver satisfactory electrochemical performances. The symmetric cell assembled with MoO₃@Zn shows a significant long cycle life of more than 1600 h at a current density of 2 mA cm^-2. Meanwhile, the MoO₃@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 Zn²⁺ conductor regulation" to dictate Zn electrodeposition and broadens novel design of vacuum evaporation for nano MoO₃ modified Zn anodes.