Molecular-Layer-Deposited Zincone Films Induce the Formation of LiF-Rich Interphase for Lithium Metal Anodes

Lithium metal anodes suffer from low Coulombic efficiency and dendritic growth owing to an unstable solid electrolyte interphase (SEI), which limit the practical applications of lithium metal anodes. Here, zincone (ZnHQ) is conformally fabricated on 3D copper nanowires (CuNWs) via a molecular layer deposition (MLD) technology. Upon polarization, the terminal oxygen of ZnHQ serves as a strong nucleophilic agent to attack Li bis(trifluoromethanesulfonyl)imide, yielding a LiF-rich SEI. This SEI facilitates the Li transport, shuts off the electron conduction, and inhibits the growth of lithium dendrites. In addition, the zinc atoms of ZnHQ induce favorable Li deposition owing to their lithiophilicity. These advantages enabled by MLD make the ZnHQ-modified CuNW (CuNW@ZnHQ) an ideal Li metal anode, which demonstrates excellent cyclability. A symmetrical cell of CuNW@ZnHQ shows high cycling stability for more than 7000 h at the current density of 1 mA cm(-2). When pairing with a Ni/Co/Mn ternary oxide cathode (NCM523), the resultant CuNW@ZnHQ||NCM full cell is cycled for 1000 cycles with a 90% capacity retention at an areal capacity of 3.2 mAh cm(-2). The MLD technology brings new opportunities for next-generation high-energy Li metal batteries.

Automated summary

By using molecular layer deposition (MLD) technology, the research team conformedly fabricated zincone (ZnHQ) on 3D copper nanowires (CuNWs), forming a stable solid electrolyte interphase (SEI), which improves the Coulombic efficiency and inhibits dendritic growth of lithium metal anodes, resulting in excellent cyclability.