【作者】 逄淑平；

【导师】 张志焜； 李桂村；

【作者基本信息】 青岛科技大学 ， 材料物理与化学， 2006， 硕士

【摘要】 一维纳米材料，如纳米棒、纳米线、纳米管、纳米片和纳米环等具有不同于块体材料的，新奇的物理化学性质而广泛引起人们的关注。氧化钒和其衍生物有特殊的氧化还原特性和层状结构，这可使多种外来的小分子、离子等插入其层间而形成相应的化合物。由于钒系化合物在锂离子电池、化学传感器、纳米器件等领域的潜在的应用前景，使合成其纳米结构、研究其性能成为近年来的热点。本论文，介绍了钒系化合物中有代表性的几种物质的合成方法，并对他们的形成机理和性质进行了分析。（1）以V₂O₅粉体为原料，加入适量的盐酸，通过简单的水热处理，得到H₂V₃O₈单晶纳米带。H₂V₃O₈单晶纳米带是一种亚稳态结构，在氧气气氛下可转化为V₂O₅纳米带。为直接得到五价钒的氧化物纳米结构，加入稀H₂O₂作为氧化剂，水热处理直接得到V₂O₅单晶纳米带，V₂O₅单晶纳米带的合成由“脱水-再结晶-劈裂”过程形成，这种方式的得到的V₂O₅纳米带的生长方向与H₂V₃O₈经在氧气中煅烧得到的V₂O₅纳米带不同。V₂O₅作为锂离子电池的电极材料，制备成纳米带后，嵌锂能力得到很大的提高。（2）通过水热法合成了Ba（VO₃）₂·H₂O单晶纳米带、Ba_1+xV₆O₁₆·nH₂O带状和环状结构以及Cu_xV₂O₅。Ba（VO₃）₂·H₂O单晶纳米带由V₂O₅粉末和Ba（OH）₂·8H₂O在适量CTMA存在的条件下，直接反应得到；而Ba_1+xV₆O₁₆·nH₂O则是通过水热处理Ba₃(V₁₀O₂₈)（H₂O）₁₉得到，在Ba_1+xV₆O₁₆·nH₂O纳米带中，有多种形貌的环状结构，如盘状、管状、圈状、车轮状等。这是第一次报道利用水热法，在无模板的情况下，成功合成钒酸盐的环状结构；钒酸铜的制备是以V₂O₅/H₂O₂溶液为钒源，通过控制Cu与V的比例，制备了不同的Cu_xV₂O₅，电化学性质分析表明，Cu_xV₂O₅作为一种理想的锂电池正极材料，但其比容量与Cu的含量有很大的关系。（3）通过V₂O₅原位氧化聚合苯胺得到聚苯胺-氧化钒复合纳米片，聚苯胺插层后，氧化钒的层间距由开始的4.38（?）增加到13.8（?），随着这种苯胺的原位插层，块体状V₂O₅被插层和剥离，最后生成木耳状聚苯胺-氧化钒复合纳米片。更多还原

【Abstract】 One-dimensional nanostructures, such as nanorods, nanowires, nanotubes, nanosheets, and nanorings, have received considerable interest due to their novel physical and chemical properties which are different from their bulk counterparts. Vanadium oxides and their derivative compounds are of interest due to their redox-activity and layered structures, which allow the insertion of various intercalation species. In recent years, the fabrication of their nanostructures has been researched intensively due to their potential applications in lithium batteries, chemical sensors or actuators, and nanodevices. In this paper, we reported several synthesis methods of some typical vanadium oxides and their derivate compounds. The growth mechanism and properties had been discussed.H₂V₃O₈ single-crystal nanobelts were synthesized by hydrothermal processing of bulky V₂O₅ powders in hydrochloric acid solution without the aid of any templates or reducing agents. H₂V₃O₈ nanobelts were metastable and can be transformed to V₂O₅ nanobelts in oxygen at 500°C. Orthorhombic V₂O₅ single-crystalline nanobelts were synthesized in the H₂O₂ aqueous solution by the same methods. The products were very pure, and the process was environmentally friendly for no impure ions, harmful reagents in the reaction solution. A probable dehydration-recrystallization-cleavage mechanism for the formation of V₂O₅ nanobelts was proposed. The growth direction of V₂O₅ nanobelts was different to that one which was prapared by sintering H₂V₃O₈ nanobelts. The experiments also demonstrated that the use of nanosized belt-like structured materials can considerably enhanced the specific discharge capacity in lithium-ion batteries.Vanadium Oxide Bronzes, such as Ba（VO₃）₂·H₂O single-crystal nanobelts, Ba_1+xV₆O₁₆·nH₂O nanobelts and seamless ring-like structures, Cu_xV₂O₅, were prapared by hydrothermal methods. Ba（VO₃）₂·H₂O nanobelts were obtained by treating V₂O₅ powders and Ba（OH）₂·8H₂O with CTMA as the surfactant. Ba_1+xV₆O₁₆·nH₂O was formed by hydrothermal treating Ba₃(V₁₀O₂₈)（H₂O）₁₉ precursor, and it is interesting that, there were several types rings in the Ba_1+xV₆O₁₆·nH₂O products, such as plate-like, tube-like, doughnut-like and wheel-like morphologies. To our knowledge that, it is the first time to report that vanadate ring-like structures can be synthesized by simple hydrothermal method without any template. Cu_xV₂O₅, prapared from V₂O₅/H₂O₂ as the vanadium source, was a perfect anode lithium material and has higher specific capacity, which can be seriously effected by the content of copper.Polyaniline-vanadium oxide nanocomposite nanosheets were prepared via an in-situ intercalation polymerization process. The interplanar spacing was increased from 4.38A to 13.8A after intercalation reaction. During the reaction, the bulk V₂O₅ powders were intercalated and exfoliated by the reaction of aniline oxidated polymerization, and form the tremeUa-like structure.更多还原