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以钨酸钠为钨源,采用水热法在不同pH值条件下制备纳米WO3粉体,通过XRD、SEM、BET等分析手段对产物的晶型结构、形貌和比表面积进行了表征,并利用紫外-可见光漫反射吸收光谱仪和测色计对所制备的样品进行光致变色性能测试。结果表明,pH=1.0和2.0时合成的产物分别为六方晶型和立方晶型的WO3粉体。其中,六方晶型的WO3所具有的规则孔道结构为光生质子H+的传递提供了良好的通道,有利于WO3粉体产生良好的光致变色性能;而立方晶型的WO3所具有的复杂的网络结构不利于光生质子H+的传递,因而光致变色性能较差。且pH=1.0时合成的刺猬状WO3粉体颗粒大小均匀,具有较大的比表面积和较高的反应活性,这也有利于粉体光致变色性能的提高。
The nano-WO3 powder was prepared by hydrothermal method at different pH values using sodium tungstate as the tungsten source. The crystal structure, morphology and specific surface area of the product were characterized by XRD, SEM and BET. The prepared samples were tested for their photochromic properties by UV-Vis diffuse reflectance spectrophotometer and colorimeter. The results show that the products synthesized at pH = 1.0 and 2.0 are hexagonal and cubic WO3 powders, respectively. Among them, the regular pore structure of hexagonal WO3 provides a good channel for the transfer of proton H +, which is conducive to good photochromic properties of WO3 powder. However, the complex network of cubic WO3 The structure is not conducive to the transfer of photo-proton H +, so the photochromic properties are poor. When pH = 1.0, the hedgehog-shaped WO3 powder has a uniform particle size, a large specific surface area and a high reactivity, which is also beneficial to the improvement of the photochromic properties of the powder.