Synthesis of NaV6O15 nanorods via thermal oxidation of sodium-intercalated 2D V2CTx and their electrochemical properties as anode for lithium-ion batteries

Abstract

Herein, a ternary vanadium bronze compound, NaV6O15 was synthesized via a low temperature thermal oxidization of sodium-intercalated V2CTx, which exhibited a higher specific capacity than the precursor V2CTx when used as the anode material for lithium-ion batteries (LIBs). The characterization results showed that the NaV6O15 nanorods spontaneously grew in the interlayers and directly damaged the layered structure of MXene. Moreover, the charge–discharge result demonstrated an initial specific discharge capacity of 350mAhg−1 under a current density of 50mAg−1 was achieved and, in particular, a specific capacity of 120mAhg−1 and a Coulombic efficiency of 100% were maintained after as many as 200 cycles at 1000mAg−1 without the lattice expansion and deformation of NaV6O15 during the lithium-ion insertion/de-insertion process. According to these results, it is therefore expected that optimizing the process further to oxidize other metal cations intercalated-MXene will exploit other nanostructures employed as the electrode in LIBs and demonstrate immeasurable performance.