Unraveling the Intrinsic Origin of the Superior Sodium-Ion Storage Performance of Metal Selenides Anode in Ether-Based Electrolytes

transfer and low interface impedance. Additionally, the ether-derived thin and smooth double-layer SEI, which is critical in facilitating ion transport, maintaining structural stability, and inhibiting electrolyte overdecomposition, is concretely visualized by transmission electron microscopy, atomic force microscopy, and depth-profiling X-ray photoelectron spectroscopy. This work provides a deep understanding of the optimization mechanism of electrolytes, which can guide available inspiration for the design of practical electrode materials.