Tajima Keisuke, Li Liang-shi, Stupp Samuel I
Department of Chemistry, Feinberg School of Medicine, Northwestern University, Evanston, Illinois 60208, USA.
J Am Chem Soc. 2006 Apr 26;128(16):5488-95. doi: 10.1021/ja058610s.
Novel hybrid materials containing silicate and charged oligo(p-phenylene vinylene) (OPV) amphiphiles were fabricated in one step by spin casting using evaporation-induced self assembly. The conjugated segments were substituted with trimethylammonium bromide groups at both termini, and tetraethyl orthosilicate served as the silicate precursor. X-ray diffraction scans of the hybrid films revealed Bragg diffraction peaks with d-spacings of 2.76 and 1.37 nm, indicating the presence of order in the hybrid structure. Optical properties of the hybrid films were characterized by UV-vis absorption and fluorescence spectra, and molecular orientation was characterized by IR spectroscopy. A rhodamine B derivative containing a triethoxysilane group was covalently incorporated into the silicate network of the films during the sol-gel reaction. Relative to disordered polymer films with identical organic composition, the ordered hybrid films revealed significantly enhanced emission from rhodamine B and also fluorescence quenching from OPV segments. These results indicate that the ordered and nanostructured environment leads to highly efficient energy transfer among organic components in these hybrid films.
通过蒸发诱导自组装旋涂一步法制备了含硅酸盐和带电的聚对苯撑乙烯撑（OPV）两亲物的新型杂化材料。共轭链段在两端被溴化三甲基铵基团取代，原硅酸四乙酯用作硅酸盐前驱体。杂化薄膜的X射线衍射扫描显示出布拉格衍射峰，其d间距为2.76和1.37 nm，表明杂化结构中存在有序性。通过紫外-可见吸收光谱和荧光光谱对杂化薄膜的光学性质进行了表征，通过红外光谱对分子取向进行了表征。在溶胶-凝胶反应过程中，一种含三乙氧基硅烷基团的罗丹明B衍生物被共价掺入薄膜的硅酸盐网络中。相对于具有相同有机组成的无序聚合物薄膜，有序杂化薄膜显示出罗丹明B的发射显著增强，以及OPV链段的荧光猝灭。这些结果表明，有序和纳米结构环境导致这些杂化薄膜中有机组分之间高效的能量转移。
