基于溶胶凝胶法制备WO3电致变色膜的溶胶特性研究

WO3是用于电致变色玻璃的阴极电致变色材料之一,采用溶胶凝胶法制备WO3薄膜具有设备简单、成本低、适合大面积制膜等特点,WO3溶胶的稳定性是一个值得深入研究的课题.采用过氧化聚钨酸法制备WO3溶胶,主要考察了钨粉-H2O2反应温度、过氧聚钨酸-乙醇反应温度、钨粉和H2O2配比等因素对溶胶稳定性的影响.研究结果表明:钨粉和H2O2反应在冰水浴中进行时控制温度在8℃以下可避免白色沉淀物过多产生.当钨粉与H2O2摩尔比为1∶7,过氧聚钨酸-乙醇反应温度为45～ 50℃,并再在80℃浓缩后可以得到稳定性和成膜性好的透明的橘黄色溶胶.

Investigation on Characteristics of WO3 Sol for Electrochromic Films Prepared by Sol-Gel Method

Tungsten trioxide is a kind of cathode electrochromic material which is normally used for electrochromic glass.Using sol-gel method to prepare WO3 films has some advantages,such as simple device,low cost,extensive production of large area films,etc.However,the stability of WO3 sol is worthy to be intensively studied.WO3 sol was prepared by poly tungsten acid peroxide method.The effects of the various factors,such as the temperature of reaction between tungsten power and hydrogen peroxide,the ratio of tungsten power to hydrogen peroxide,the temperature of reaction between poly tungsten acid peroxide and ethyl alcohol,on the stability of the sol have been studied.The results showed that the too much white sediment could be avoided when the temperature of reaction between tungsten powder and H2O2 was controlled below 8 ℃.The transparent orange sol with high stability and good film-forming property could be obtained at the following optimized conditions,that:mole ratio of tungsten powder to H2O2 is 1 ∶ 0.7,temperature of reaction between poly tungsten acid peroxide and ethyl alcohol is 45-50℃,and then they are concentrated at 80℃.