氧化锌/二氧化硅复合膜的结构色研究

Study of Structural Colors of ZnO/SiO_(2)Composite

采用静电自组装技术,以氧化锌(ZnO)和二氧化硅(SiO_(2))溶胶颗粒为前驱体,通过控制双组分膜层的不同厚度,制备出结构色鲜艳的ZnO/SiO_(2)复合膜,并利用分光测色仪、多角度分光光度仪及扫描电子显微镜等研究复合膜的颜色、微观结构和形态特征。研究结果发现,ZnO/SiO_(2)复合膜的亮度和色度均较单一组分薄膜的高,复合薄膜的颜色仍随厚度和观察角度的变化而变化。通过对薄膜的微观结构分析,结合其厚度随周期数的变化规律,发现复合薄膜的厚度随着自组装循环次数的增加而增加,薄膜中的纳米粒子并没有形成明显的高低折射率交替分布的双层结构,可能形成的是高折射率层(H层)、有效折射率层(eff层)和低折射率层(L层)的多层微观结构。这种特殊的多层结构与光作用发生干涉,形成了鲜亮度和饱和度更高的结构色。

ZnO/SiO_(2)composite films with controlling thickness and vivid structural colors were designed by the electrostatic self-assembly technique from zinc oxide(ZnO)and silica(SiO_(2))sol particles precursors.The structural color,microstructure and morphology of the films were analyzed using spectrocolorimetry,multi-angle spectrophotometry and scanning electron microscope(SEM).The results showed that the ZnO/SiO_(2)composite films exhibited higher brightness and chroma compared to the films composed of single components.The color of the composite films varied with the changes of thickness and observation angles.By examining the microstructure and the films thickness varying with the increasing assembly cycles,the film could hardly form a distinct bilayer structure with alternating high and low refractive indices.In fact,it was prone to forming a multilayer microstructure,which had a high refractive layer(H layer),an effective refractive layer(eff layer),and a low refractive layer(L layer).The more vivid and saturated structural colors were probably originated from the multilayer thin flm interference.