Controlled Hydrothermal Growth and Li(+) Storage Performance of 1D VO(x) Nanobelts with Variable Vanadium Valence

One-dimensional (1D) vanadium oxide nanobelts (VO(x) NBs) with variable V valence, which include V(3)O(7)·H(2)O NBs, VO(2) (B) NBs and V(2)O(5) NBs, were prepared by a simple hydrothermal treatment under a controllable reductive environment and a following calcination process. Electrochemical measurements showed that all these VO(x) NBs can be adopted as promising cathode active materials for lithium ion batteries (LIBs). The Li(+) storage mechanism, charge transfer property at the solid/electrolyte interface and Li(+) diffusion characteristics for these as-synthesized 1D VO(x) NBs were systematically analyzed and compared with each other. The results indicated that V(2)O(5) NBs could deliver a relatively higher specific discharge capacity (213.3 mAh/g after 50 cycles at 100 mA/g) and median discharge voltage (~2.68–2.71 V vs. Li/Li(+)) during their working potential range when compared to other VO(x) NBs. This is mainly due to the high V valence state and good crystallinity of V(2)O(5) NBs, which are beneficial to the large Li(+) insertion capacity and long-term cyclic stability. In addition, the as-prepared VO(2) (B) NBs had only one predominant discharge plateau at the working potential window so that it can easily output a stable voltage and power in practical LIB applications. This work can provide useful references for the selection and easy synthesis of nanoscaled 1D vanadium-based cathode materials.