水热pH调控合成WO_(3)纳米线及其电致变色性能研究

Synthesis and Electrochromic Properties of WO_(3) Nanowires by Using Regulating pH Value Hydrothermal Method

采用水热法研究了反应体系pH值对WO_(3)粉体的微观形貌和结构的影响,并利用扫描电子显微镜(SEM)及X射线衍射(XRD)进行表征。结果表明:考察pH值范围内均可获得六方相的WO_(3)材料,pH值的增加不仅有利于纳米线的形成,而且可以提高长径比和取向性。当pH=1.8时,WO_(3)纳米线的尺寸均匀,且基于该纳米线制备的薄膜电极具有较大的光学调制(71.5%@633 nm)和较高的着色效率(32.6 cm^(2)·C^(-1)),可实现大面积、柔性基底或图案化应用。

The effects of pH value of hydrothermal system on the microstructure and structure of WO_(3) were comprehensively studied by using scanning electron microscopy(SEM)and X-ray diffraction(XRD)analysis.It is found that WO_(3) crystals with hexagonal structure were obtained at various pH values within the inspection range.The increase in pH value was conducive to the formation of nanowires,while the aspect ratio and orientation of the nanowires were also improved.An electrochromic film was further prepared by spraying the dispersion of WO_(3) nanowire obtained at pH=1.8.The film exhibited a high optical modulation(71.5%@633 nm)and a high coloring efficiency(32.6 cm^(2)·C^(-1)),which showed great potential for large-area devices,flexible substrates or patterned structure applications.