One-Step In Situ Synthesis of Three-Dimensional NiSb Thin Films as Anode Electrode Material for the Advanced Sodium-Ion Battery

A low-cost, facile and highly efficient in situ solvothermal reaction has been developed for the first time to synthesize, by using a 3D Ni foam template, three-dimensional nickel-antimony (3D NiSb) thin films as anode electrode materials for use in sodium-ion batteries (SIBs). The structure design and preparation have proved reasonable and efficient, leading to excellent electrochemical properties. At current densities of 100, 200 and 400 mAg(-1), specific capacities of 643.8, 520.5 and 378.6 mAhg(-1), respectively, could be obtained. Additionally, a specific capacity of 420 mAhg(-1) could be achieved after 100 cycles at a current density of 100 mAg(-1). This could be attributed to the special 3D binder-free conductive network connecting the NiSb nanoparticles and the 3D contact area with the electrolyte, which is beneficial for the charge-transfer kinetics and electrochemical performance. Moreover, the porous structure offers enough space to alleviate the volume changes and stress generated in the sodiation/desodiation process. Most importantly, the 3D porous Ni foam, as a support for NiSb nanoparticles, can effectively prevent the agglomeration of the NiSb and Na3Sb nanoparticles. Therefore, such a unique NiSb anode material may be of great significance in next-generation energy storage devices.