电化学沉积制备V2O5薄膜电极的表面结构及储钠性能

以含有CTAB的V₂O₅溶胶为电解液，采用电沉积法在不锈钢基体上沉积V₂O₅薄膜前体，经300℃烧结处理后制备了无黏结剂和导电剂的V₂O₅纳米薄膜电极。XRD测试表明该方法制备的V₂O₅薄膜是含水相的V₂O₅·nH₂O，与未添加CTAB制备的薄膜相比，其层间距明显变大。FESEM和AFM测试发现CTAB辅助电沉积制备的V₂O₅薄膜具有粗糙多孔的表面形貌；XPS测试表明CTAB辅助电沉积制备的V₂O₅薄膜中含有更多的低价钒离子（V⁴⁺）。电化学测试发现该方法制备的V₂O₅薄膜具有优异的嵌/脱Na⁺循环稳定性；与未添加CTAB制备的薄膜相比，CTAB辅助电沉积制备的V₂O₅薄膜具有更好的电化学反应可逆性、更强Na⁺扩散性能和更高的储钠比容量，是一种非常有应用前景的钠离子电池正极材料。

Surface morphology and sodium storage performance of V2O5 thin film electrode prepared by CTAB assisted electrodeposition

New V₂O₅ nanofilm electrodes without binder and conductive agents were fabricated by sintering the V₂O₅ film precursor at 300℃ on stainless steel substrates, which were coated from CTAB-containing V₂O₅ sol gel electrolyte by electrodeposition. X-Ray diffraction (XRD) indicated that V₂O₅ in the new V₂O₅ film was hydrated V₂O₅·nH₂O and the film had lager interlamellar spacing than V₂O₅ film prepared without CTAB. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) results showed that the new V₂O₅ film possessed a rough porous surface morphology. X-Ray photoelectron spectroscopy (XPS) results suggested that the new V₂O₅ film electrode contained more V⁴⁺ than the V₂O₅ film electrode prepared without CTAB. Electrochemical study demonstrated that the new V₂O₅ film electrode had excellent Na⁺ insertion/extraction stability. Compared to the V₂O₅ film electrode prepared without CTAB, the new V₂O₅ film electrode exhibited better electrochemical reaction reversibility, enhanced Na⁺ diffusion performance, and higher sodium storage specific capacity, which could be a very promising cathode material for sodium ion batteries.