21世纪以来，人们对能源需求的不断增长对可持续发展和能源环保是一个非常重要且具有巨大的挑战性问题。在现有能量储存技术中，锂离子电池由于具有高能量密度，长循环寿命以及无记忆效应等优点而受到关注。然而锂离子电池在电动汽车和电网级储能等大规模能源储存应用上还有待进一步开发。为了实现规模化应用，制备高功率密度的电池是迫切必需的。因此寻找理想的高能量密度和功率密度的电极材料具有非常重大意义的。钒氧化物在可再充锂离子电池中是非常好的正极材料，具有很高的的容量和非常丰富的资源。

然而，钒氧化物的电化学性能仍然存在许多缺陷，主要原因是其具有较低的电子电导率和离子电导。电子电导率比较低会影响其高倍率充放电性能，而较低的离子电导率会使锂离子在钒氧化物中脱嵌时受到更大阻力，在影响其容量的同时使循环稳定性变差。在本文探索了有效的方法来改进这些缺陷，从而会提高其电化学性能。

本论文通过水热方法以及固相烧结法制备了钴掺杂的钒氧化物纳米线、 NH₄V₃O₈纳米线和多孔二氧化钒纳米线等锂离子电极材料。主要内容如下：

（1）通过水热方法合成了Co掺杂的钒氧化物纳米线。作为锂电池电极材料Co掺杂的钒氧化物纳米线相比于块状V₂O₅，在1 A/g 电流密度下，其首次容量为1603 mAh/g，在300圈后其比容量仍能保持640 mAh/g，显示出其作为锂电池负极材料具有广泛的应用前景。（2）通过调节水热时间与pH值，成功制备NH₄V₃O₈纳米线。作为锂电池正极材料，在0.1 A/g电流密度下该材料初始容量为175 mAh/g，高于对照样块状NH₄V₃O₈的循环初始容量（160 mAh/g），经过100圈循环后NH₄V₃O₈纳米线容量为125 mAh/g，其容量保持率高达71%，远高于块状NH₄V₃O₈ (56 mAh/g, 35%)。（3）通过在氮气气氛下控制不同温度烧结NH₄V₃O₈纳米线得到不同价态的钒氧化物。由于加热过程中的氨气释放，通过调节烧结温度，利用氨气的还原性，成功制备得到不同价态的钒氧化物（VO₂, V₂O₃等）。（4）结合水热法和固相烧结法制备了多孔VO₂纳米线，其具有较高的比表面积（46.7 m²/g）远高于VO₂纳米线（8 m²/g），作为正极电极材料，多孔VO₂纳米线在1 A/g的大电流密度下500圈的容量保持率高达90%，远高于VO₂纳米线的容量保持率75%。综上所述，多孔VO₂纳米线展示出了更优异循环稳定性和倍率性能。

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