标题： 偶极分子在SiO$_2$混合有机无机薄膜中的聚集：使用银纳米颗粒作为分子聚集的抑制剂 显示英文标题

标题： Aggregation of dipolar molecules in SiO$_2$ hybrid organic inorganic films: use of silver nanoparticles as inhibitors of molecular aggregation

摘要： 杂化有机-无机材料在二阶非线性光学光子器件中的技术实现强烈依赖于基质材料容纳高负载偶极分子而不发生聚集的能力。 一些有机分子常用于减弱这类材料中偶极分子之间的吸引作用，但它们作为分子聚集抑制剂的效率受到其极化率的限制。 在本工作中，我们报告了银纳米颗粒作为掺杂偶极分子的杂化有机-无机薄膜中分子聚集的抑制剂的使用。 银纳米颗粒具有较大的极化率，使它们成为抑制二阶非线性光学偶极分子之间静电相互作用的理想组分。 本工作中银纳米颗粒的平均直径为70.5纳米，它们是使用硝酸银（AgNO$_3$）作为前驱体和氨基乙基氨基丙基三甲氧基硅烷作为还原剂合成的。 这些纳米颗粒被浸入掺杂偶极染料的SiO$_2$杂化有机-无机溶胶-凝胶薄膜中，以研究它们作为偶极染料聚集抑制剂的效果。 通过透射电子显微镜和紫外-可见光谱分析确认了固体薄膜中银纳米颗粒的存在。 紫外-可见光谱分析也被用来监测SiO$_2$薄膜中偶极染料的聚集情况。 我们发现，在室温下，银纳米颗粒在抑制染料聚集方面比有机抑制剂表现更好。 显示英文摘要

摘要： The technological implementation of hybrid organic-inorganic materials in second order nonlinear optical photonic devices depends strongly on the ability of the host matrixes to contain high loads of dipolar molecules without aggregation. Some organic molecules are often used to diminish the attracting interactions between dipolar molecules in such kind of materials, but their efficiency as inhibitors of molecular aggregation is limited by their polarizability. In this work, we report the use of silver nanoparticles as inhibitors of molecular aggregation in hybrid organic-inorganic films doped with dipolar molecules. The large polarizability of the silver nanoparticles makes them ideal moieties for the inhibition of the electrostatic interactions between dipolar nonlinear optical molecules. The average size of the silver nanoparticles in this work was 70.5 nm in diameter, they were synthesized using silver nitrate (AgNO$_3$) as precursor and aminoethylaminopropyltrimethoxysilane as reducing agent. These nanoparticles were immersed in SiO$_2$ hybrid organic-inorganic sol-gel films doped with dipolar chromophores to study their effect as inhibitors of dipolar chromophores aggregation. The presence of the silver nanoparticles in the solid films was confirmed by transmission electronic microscopy and UV-Visible spectroscopy. UV-Visible spectroscopy was also used to monitor the dipolar chromophores aggregation in the SiO$_2$ films. We found that, at room temperature, silver nanoparticles are good inhibiting chromophores aggregation in comparison with the performance of organic inhibitors.