%0 Journal Article
%T <br>
%A 周鹏
%A 安琴友
%A 盛进之
%A 董君
%A 高崇伟
%A 麦立强
%J 物理化学学报
%D 2020
%R 10.3866/PKU.WHXB201906046
%X 钠具有资源丰富、成本低廉等优势，因此钠离子电池被认为是未来替代锂离子电池的最佳候选者之一。然而，寻找合适的电极材料是当前制备高性能钠离子电池面临的难题之一。在众多候选材料中，钒酸盐材料通过引入阳离子增加钒的配位数，使得材料结构的稳定性得到提高，从而改善了钠离子电池的电化学性能。本文研究了一种原位相分离法合成V2O5/Fe2V4O13纳米复合材料。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)等对电极材料形貌、组成和结构进行了表征。实验结果显示，V2O5/Fe2V4O13纳米复合材料相对于V2O5纳米线材料，结构更加稳定，在0.1 A·g-1电流密度下，初始放电容量由295.4 mAh·g-1提升到342 mAh·g-1，循环100圈容量保持率由26.6%提高到65.8%，获得了更加优异的倍率性能(在1.0 A·g-1电流密度下，容量由44 mAh·g-1提高到160 mAh·g-1)。因此，V2O5/Fe2V4O13纳米复合材料的研究为开拓新型高性能钠离子电池负极材料拓宽了思路。<br>Sodium has the advantages of being an abundant resource and having a low cost; thus, sodium ion batteries are considered as one of the best candidates for replacing lithium ion batteries in the future. However, the radius of the sodium ion is larger than that of the lithium ion, and the de-intercalation of the sodium ion will seriously damage the crystal structure of most electrode materials during the charging and discharging process, which considerably limits its charge-discharge specific capacity, cycle performance, and rate performance. However, finding appropriate electrode materials is one of the difficulties in fabricating high-performance sodium ion batteries. Among the many candidate materials, vanadate materials can improve the stability of material structures by introducing cations to increase the coordination numbers of vanadium, thus improving the electrochemical performance of sodium ion batteries. In this paper, an in situ phase separation method to fabricate V2O5/Fe2V4O13 nanocomposite materials is reported. First, we synthesized hydrated crystalline Fe5V15O39(OH)9·9H2O nanomaterials using a water bath heating method; then, we in situ constructed two-phase nanocomposite V2O5 and Fe2V4O13 from the single phase by further high-temperature treatment. The morphology, composition, and structure of the electrode materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy(FTIR), as well as other methods. The V2O5/Fe2V4O13 nanocomposite materials were found to have a more stable structure, higher initial discharge capacity (342 mAh·g-1 at a current density of 0.1 A·g-1), longer cycle life, and better rate performance than V2O5 nanowires. Therefore, this research on V2O5/Fe2V4O13 nanocomposite materials has broadened ability to develop new high-performance anode materials for sodium ion batteries
%U http://www.whxb.pku.edu.cn/CN/Y2020/V36/I5/1906046