One-pot solvothermal method to fabricate 1D-VS4 nanowires as anode materials for lithium ion batteries

1D-VS4 nanorods have been successfully fabricated through a simple facial solvothermal method for the first time. SEM, Raman spectrum, FTIR and UV-vis are adopted to investigate the morphology, structure and composition of prepared nanocomposites, and results show that obtained VS4 is presented as uniform nanorods and is mainly composed by monoclinic VS4 with high crystallinity and purity. Moreover, these prepared VS4 nanorods have a uniform morphology as well as a small crystal size of 1-2 mu m and a diameter of 20-60 nm. Electrochemical properties of VS4 nanorods as anode electrodes have shown VS4 is great in electrical conductivity, rate performance and service life. The first discharge has its specific capacity reaching 574.3 mAh at the current density of 200 mA g(-1), and the reversible residual specific capacity could be retained to 439.3 mAh g(-1) after 120 cycles. When current density is increased to 2 A g(-1), the remaining capacity still remained as 267.3 mAh g(-1), indicating good conductivity and excellent rate performance in VS4 based LIB. The small internal impedance (100 O) also indicates that the VS4 nanorod anode has a high conductivity, thus its superior electrochemical performance is promoted. Finally, we have carried out DFT calculations to explain how Li ions have been inserted into bulk and 1D-VS4 nanorods; and the fast Li ion migration in the 1D-VS4 nanorods with the NEB barrier is only 138.5 meV, and also the strong absorption ensures its excellent electrochemical performance.