Ni-Doped SnO₂ Nanoparticles Anchored on\nCarbon Nanotubes as Anode Materials for Lithium-Ion Batteries

Abstract

In this work, we synthesized the\nSnO₂–Ni-carbon\nnanotube (CNT) (SNC) composite anode material by hydrothermal and\nball milling methods. In this ternary composite, Ni-doped SnO₂ is firmly anchored on the few-walled CNTs. Nano-Ni doping\nprevents the coarsening of Sn, enhances the electron conductivity,\nand stabilizes the structure during the process of charging and discharging.\nIn addition, the CNTs can effectively buffer the volume change of\nSnO₂ and improve the conductivity as well as shorten the\ntransport distances of electron and Li⁺. Accordingly, the\nSNC shows a large reversible capacity of 1245.7 mA h g^–1 after 400 cycles at 0.2 A g^–1. With a capacity\nof 1078.2 mA h g^–1 after 850 cycles at 1.0 A g^–1, it exhibits a long-term cycling stability. Meanwhile,\nthe capacity can still reach 666.5 mA h g^–1 at 5.0\nA g^–1 with excellent rate capability. The performance\nand stability of this Ni-doped composite are much better than those\nof SnO₂, implying that SNC is exceedingly prospective as\nan anode material for lithium-ion batteries.