Regulating the Interfacial Electric Field for a Stable Lithium Metal Anode

In our work, a homogeneous Au nanosheet layer is coated on the surface of a LiB alloy anode through in situ replacement of free Li to affect the deposition behavior of Li. The highly conductive Au nanosheet network provides a homogeneous electric field distribution on the LiB anode, which effectively reduces the local current density and induces uniform Li deposition. Moreover, the uniformly distributed Au nanosheet layer provides a great deal of electrochemically active centers and nucleation sites, which result in a uniform interfacial reaction of Li deposition in the Au nanosheet layer, thereby greatly slowing down the growth of Li dendrites. On the other hand, the two-dimensional Au nanosheet structure provides a rich internal surface area and a mass of electronic pathways all over the surface of the LiB alloy anode, which significantly enhances the diffusion flux of Li ions and regulates its electrodeposition behavior. At the same time, it effectively alleviates the huge volume change during the repeated stripping and plating of Li. The modified anode exhibits a distinguished electrochemical performance with an ultralong lifespan of up to 1250 h, as well as a low overpotential (<35 mV at 1.0 mA cm^–2) at a Li deposition of 1.0 mA h cm^–2.