水热法制备纳米VO2及其相变机理的研究进展

VO_2是一种具有极大应用价值的功能材料,其潜在的应用产品有智能窗、热敏电阻、锂离子电池电极等,但纳米VO_2的大批量制备技术成了制约其应用的关键因素。水热合成法反应条件温和、对环境的污染小、能耗低、价格便宜;易控制化学价态、晶相、产物纯度较高;反应无需煅烧晶化,可以减少煅烧过程中产生的团聚,可获得通常条件下难以得到的纳米粉体,粉体粒径分布较窄、晶型和形貌可控,有望用于VO_2纳米结构的大量合成。聚焦于水热合成法制备纳米VO_2及其相变机理的研究进展,着重介绍了不同形貌与物相的纳米VO_2的水热合成制备方法、物相转换及机理、水热过程中VO_2的生长机制。最后,指出了水热法制备VO_2所面临的一些问题,并展望了未来的发展方向。

A Survey on Hydrothermal Syntheses of Nano-VO2 and Crystal Phase Transition Mechanisms

As a kind of functional materials with great potential applications,VO2 has been applied in many de-vices,such as thermochromic smart windows,thermal resistor,lithium ion battery electrodes and so on.However, lack of massive production techniques is the crucial constraint on the extensive application of VO2 .Hydrothermal process has been expected to facilitate large-scale synthesis of VO2 nanostructures due to its great superiority.Firstly, it is often applied under mild reaction conditions,emits low environmental pollution,and consumes low energy.Se-condly,the process has the ease of control over product′s chemical valence and crystal phase,high purity,without cal-cination for crystallization,thus can reduce agglomeration.Thirdly,hydrothermal process can obtain nanopowders difficult to obtain under normal conditions,and the particle size distribution is narrow,morphologies and crystal forms are controllable.In this paper,the research progress of hydrothermal synthesis of nano-VO2 and the phase transfor-mation mechanism are introduced.The hydrothermal synthesis method,phase transition and growth mechanism of VO2 with different morphologies and phases in the hydrothermal process are emphatically introduced.Finally,some problems and challenges regarding to the hydrothermal preparation of nano-VO2 are also pointed out,and the future development direction are put in prospect.