Long-Life Sodium Metal Anodes Achieved by Cuprous Oxide-Modified Ni Foam Host

Sodium metal is considered as a potential anode material for future energy-storage systems. However, the practical application of Na is hindered by the infinite dimension change and dendrite growth during Na stripping/plating. Herein, a nanoflowered cuprous oxide-modified nickel foam (CNF) matrix is used as a stable host to guide Na nucleation behavior and suppress dendrite growth. Tailored CNF shows a 3D porous core-shell cylindrical structure with Cu2O as the shell and special Ni as the core. The shell of CuO2 can reduce the nucleation barrier of Na by reacting with sodium. The core of Ni provides a strong skeleton with high electrical conductivity, good mechanical ductility, and a rich porous structure. The unique matrix structure can direct the homogeneous nucleation of sodium metal and restrict its deposition within matrix pores, suppressing the volume expansion and dendrite growth of sodium metal. As a consequence, the Na/CNF anode exhibits an excellent stability over 1000 cycles with a capacity of 1 mAh cm(-2) at 1 mA cm(-2). Moreover, the full battery exhibits excellent performance over 300 cycles at a high rate (5 C). A new avenue is opened, herein, for practical applications of sodium metal anodes in rechargeable Na batteries.