VO2 nanobelts decorated with a secondary hydrothermal chemical lithiation method for long-life and high-rate Li-ion batteries

Abstract

In this work, pre-lithiated VO2(B) nanobelts are synthesized by a two-step hydrothermal method. After pre-lithiation, the VO2(B) nanobelts exhibit a uniformly dispersed morphology with a large specific surface area. Compared to pure VO2(B) nanobelts, the pre-lithiated VO2(B) nanobelts show much better electrochemical performance in terms of cycling stability and high-rate capability. The lithium-ion diffusivity in the pre-lithiated VO2(B) nanobelts is enhanced due to enlargement of the crystal lattice after pre-lithiation. The pre-lithiated VO2(B) nanobelt cathode delivers an initial specific capacity of 264 mA h g–1 at 0.1 A g–1 with a capacity retention of 81.6% after 100 cycles, which is superior to that obtained for pure VO2(B) under the same conditions (initial capacity of 221.5 mA h g–1 and capacity retention of 63.3%). Moreover, the pre-lithiated VO2(B) nanobelt electrode exhibits outstanding long-term cycling stability (capacity retention of 87.2% after 800 cycles at 1000 mA g–1). These results indicate that pre-lithiated VO2(B) nanobelts have great potential to be applied as an advanced cathode material for next-generation lithium-ion batteries.