Core−shell nanoparticles with 1,4-bis(o-cyanostyryl)benzene (CSB), which is a commonly used fluorescent agent, as the core and with nanosilica particles as the shell were prepared by a self-templating method. The morphologies, structure, particle size distribution, and optical properties of the resulting CSB−SiO₂ nanoparticles were characterized. The effects of the reaction conditions on the structure and morphologies, their stability in aqueous solutions, and their optical properties were investigated. During the process, an oil-in-water emulsion system was formed, and the core−shell nanoparticles were obtained by a rapid solidification reaction from the outer surface toward the center of the emulsion. The whole process required neither surface treatment for nanosilica particles nor additional surfactant or stabilizer. Experimental results indicated that the resulting CSB−SiO₂ nanoparticles were perfectly spherical with smooth particle surfaces and had distinct core−shell structures. The CSB−SiO₂ nanopaticles had good stability in aqueous solutions for a period of time. The particle size and shell thickness could be readily tuned by altering reaction conditions. The resulting CSB−SiO₂ core−shell nanoparticles exhibited strong UV absorption and fluorescence emission. In addition, the mechanism of the self-templating method for forming core−shell nanoparticles is discussed.

中文翻译：

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核-壳结构的1,4-双（邻氰基苯乙烯基）苯-二氧化硅纳米粒子的合成及反应条件的影响

通过自模板法制备了以1,4-双（邻氰基苯乙烯基）苯（CSB）为核心，以纳米二氧化硅颗粒为壳的核壳纳米粒子。所得CSB-SiO ₂的形态，结构，粒度分布和光学性质表征了纳米颗粒。研究了反应条件对结构和形貌，它们在水溶液中的稳定性以及它们的光学性质的影响。在此过程中，形成了水包油乳液体系，并通过从乳液外表面到中心的快速固化反应获得了核壳纳米粒子。整个过程既不需要纳米二氧化硅颗粒的表面处理，也不需要额外的表面活性剂或稳定剂。实验结果表明，所得CSB-SiO ₂纳米颗粒为球形，表面光滑，具有明显的核壳结构。CSB-SiO ₂纳米颗粒在水溶液中一段时间​​内具有良好的稳定性。通过改变反应条件可以容易地调节粒度和壳厚度。所得的CSB-SiO ₂核壳纳米粒子表现出较强的UV吸收和荧光发射。此外，还讨论了自模板化方法形成核壳纳米粒子的机理。