ZnS-opal与反opal结构ZnS光子晶体的组装

Fabrication and characterization of ZnS-opal and inverse opal ZnS photonic crystals

以单分散SiO2微球为基元,在75%～80%湿度、30～45℃恒温密闭烘箱中垂直快速组装opal模板;以Zn(NO3)(20.035mol/L)、TAA乙醇溶液(0.05mol/L)为前体,通过溶剂热法充填形成ZnS-opal复合光子晶体;ZnS-opal复合光子晶体在2%～5%的HF溶液中浸泡4～5h后卸载模板,制得反opal结构ZnS基光子晶体;采用XRD、SEM、UV-Vis测试手段对反opal结构ZnS基光子晶体形貌、物相和光学性能进行了表征。结果表明:溶剂热法多次充填可使ZnS纳米晶在模板密堆积形成的空隙中均匀成核;经过酸处理的ZnS-opal中SiO2微球溶解、坍塌,形成蜂窝状三维有序介孔和反opal结构ZnS基光子晶体;相同粒径SiO2微球组装的opal模板、ZnS-opal以及反opal结构ZnS光子晶体均表现出光子带隙特性,但反opal结构ZnS光子晶体带隙位置相比前两者发生了蓝移。

Opal templates were rapidly assembled from monodisperse SiO2 microspheres as building blocks by vertical sedimentation in an airtight oven at 30-45 ℃ and in a certain humidity. With a precursor composed of 0.035mol/L Zn （NO3）2 and 0.05mol/L TAA ethanol solution, ZnS photonic crystals with opal structure were prepared by solvothermal synthesis method repeatly. ZnS photonic crystals with inverse opal structure were obtained by removing the opal template after immersing in 2%-5% HF acid for 4-5 h. The morphology, component and optical properties of the synthetic samples were tested and compared. Results of XRD, SEM, and UV-Vis indicated that ZnS nanocrystals can grow in and fill in the void of opal template, and SiO2 microspheres of templates are dissolved so as to form some three dimensional ordered porous structure and to form the inverse opal ZnS photonic crystals. Compared with opal templates, ZnS-opal and inverse opal ZnS photonic crystals assembled with SiO2 spheres in the same diameter show good optical properties and exhibited photonic band gap. The photonic band gap position of inverse opal ZnS moves towards UV area compared with opal and ZnS-opal.