采用改进的St?ber法合成了单分散SiO_2微球,通过垂直沉积组装成蛋白石结构光子晶体.再使用电化学法在组装的SiO_2微球表面生成聚(3,4-乙撑二氧噻吩)(PEDOT),得到核-壳结构的SiO_2@PEDOT光子晶体复合膜.测试了SiO_2@PEDOT光子晶体薄膜的反射光谱、循环伏安曲线、多电位紫外反射光谱、对比度及响应时间等光学、电化学及电致变色性能.结果表明,该光子晶体薄膜在变色时颜色亮丽,其色差值(26.82)比纯PEDOT薄膜(18.07)提高很多,并且最大对比度可达39.8%,高于纯PEDOT薄膜的27.4%,同时响应时间变快.此实验结果说明将光子晶体结构引入导电聚合物中,能够提高其电致变色性能.
PEDOT is a kind of promising intrinsical conductive polymer because of the high chemical and electrochemical stability, low band gap, high conductivity, and excellent transparency in the doped state. It has been investigated in many diverse research fields such as basic polymer science, material science, electrochemistry, electronics and optoelectronics, photovoltaics, corrosion protection, and biosensors. However, the electrochromic devices based on PEDOT exist some drawbacks including low contrast, single color and long response time, which is harmful for practical application. Photonic crystals have drawn a lot of attention due to the possibility to control light propagation. We use silica to assemble the photonic crystals in this paper. Firstly, monodisperse silica particles were prepared by the modified St?ber method, and then the Si O2 opal film was obtained by a vertical deposition self-assembly method. Then, poly(3,4-ethylenedioxythiophene)(PEDOT) was coated outside the Si O2 opal template via electrochemical methods, and finally the core-shell structured Si O2@PEDOT photonic crystal films were obtained. The properties of Si O2@PEDOT were characterized by scanning electron microscope(SEM), transmission electron microscope(TEM), reflection spectra, cycle voltammograms, contrast and response time. The SEM and TEM results show that the Si O2 microsphere arranged in the form of hexagonal close packing, and the Si O2@PEDOT has spherical core-shell structure with a rough surface. The diameter of the Si O2 core is 330 nm, and the thickness of PEDOT shell is about 15 nm. Cycle voltammograms indicate that the electrochemical property of Si O2@PEDOT film is better than the pure PEDOT film. And the chromatic difference analysis of Si O2@PEDOT film(28.62) is better than PEDOT film(18.07), too. Through the UV reflectance spectra, contrast and response time measurements, it is found that the color of the Si O2@PEDOT film is bright and vibrant with a maximal contrast of 39.8%, which is superior