Ultrathin Surface Coating Enables the Stable Sodium Metal Anode

A stable Na metal anodeis is reported by forming an artificial solid electrolyte interphase via a low-temperature plasma-enhanced atomic layer deposition technology. It is discovered that an ultrathin layer of Al₂O₃ layer (2.8 nm) can protect Na metal from electrolyte decomposition, prevent 3D dendrite formation, and significantly enhance its cycle stability in a carbonate-based electrolyte.