Controlled Hydrothermal Growth and Li+ Storage Performance of 1D VOx Nanobelts with Variable Vanadium Valence

Abstract

One-dimensional (1D) vanadium oxide nanobelts (VOx NBs) with variable V valence, which include V3O7·H2O NBs, VO2 (B) NBs and V2O5 NBs, were prepared by a simple hydrothermal treatment under a controllable reductive environment and a following calcination process. Electrochemical measurements showed that all these VOx 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 VOx NBs were systematically analyzed and compared with each other. The results indicated that V2O5 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 VOx NBs. This is mainly due to the high V valence state and good crystallinity of V2O5 NBs, which are beneficial to the large Li+ insertion capacity and long-term cyclic stability. In addition, the as-prepared VO2 (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.

Organic Molecular Intercalated V3O7·H2O with High Operating Voltage for Long Cycle Life Aqueous Zn‐Ion Batteries

“…It is speculated that the introduction of DP may increase the interlayer spacing of vanadium oxide compounds. [ 23 ] Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were performed to explore the morphologies and detailed structures of the VO‐DP samples. As shown in Figure 1d and Figure S2 (Supporting Information), VO‐DP displays a thorn flower‐like structure composed of nanoribbons of several nanometers in size with a longitudinal dimension of several micrometers.…”

Recrystallization of Single-Crystalline VO2 Microtube Arrays on V2O5 Substrate

“…At present, at least 52 stable and metastable phases of the vanadium-oxygen system have been obtained [17]. These phases may transform from one-to-another via recrystallization [18,19], redox reaction [20], or thermal treatment [21]. For a further understanding of the microstructure and phase evolution characteristics of single-crystalline VO 2 microtube arrays on V 2 O 5 substrate during heating and cooling, a recrystallization study of single-crystalline VO 2 microtube arrays on V 2 O 5 substrate is carried out in this work.…”