Optically active SiO₂/TiO₂/polyacetylene multilayered nanospheres: Preparation, characterization, and application for low infrared emissivity

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• 作者：Xiaohai Bu ; Yuming Zhou ; Man He ; Zhenjie Chen ; Tao Zhang
• 关键词：Optical activity ; Substituted polyacetylenes ; SiO2/TiO2 ; Multilayered nanosphere ; Low infrared emissivity
• 刊名：Applied Surface Science
• 出版年：1 January, 2014
• 年：2014
• 卷：288
• 期：Complete
• 页码：444-451
• 全文大小：1568 K

文摘

Optically active silica/titania/substituted polyacetylene (SiO₂/TiO₂/SPA) multilayered core-shell nanocomposite was successfully prepared by the combination of subsequent surface titania deposition and polymer grafting on the bare silica nanosphere. The chiral amino acid-based SPA copolymer serving as the organic shell was optically active and adopted a predominately single-handed helical conformation. The SiO₂/TiO₂/SPA nanospheres were characterized by Fourier transform infrared spectroscopies (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) to record the formation of the multilayered architecture and the results clearly showed that the inorganic/organic hybrid nanoparticles exhibited hierarchical multilayered core-shell construction. The SPA outer shell experienced an enhancement in thermal stability and still remained considerable optical activity after grafting to the SiO₂/TiO₂ nanosphere. The SiO₂/TiO₂/SPA nanocomposite had an infrared emissivity value (蓻 = 0.548) at the wavelength of 8-14 渭m which was much lower than each of its components. The reduced infrared emissivity values proved that the strengthened interfacial interactions originating from the coating SPA had an effective synergistic effect with the semiconductive anatase TiO₂ nanoparticles on silica sphere in lowering the infrared emissivity value.