Sola-Llano Rebeca, Martínez-Martínez Virginia, Fujita Yasuhiko, Gómez-Hortigüela Luis, Alfayate Almudena, Uji-I Hiroshi, Fron Eduard, Pérez-Pariente Joaquín, López-Arbeloa Iñigo
Departamento de Química Física, Universidad del País Vasco, UPV/EHU, Apartado 644, 48080, Bilbao, Spain.
Department of Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200F, 3001, Heverlee, Belgium.
Chemistry. 2016 Oct 24;22(44):15700-15711. doi: 10.1002/chem.201601736. Epub 2016 Sep 15.
In this work, hemicyanine dye LDS 722 is encapsulated into the 1D elliptical nanochannels of MgAPO-11 aluminophosphate by a crystallization inclusion method. The synthesis of the hybrid material has been optimized through a systematic variation of the crystallization conditions in order to obtain pure and large crystals (around 20 μm×30 μm) suitable for optical applications. The tight fitting between the molecular size of the guest dye and the pore dimensions of the host has favored a rigid planar conformation of the dye, restricting its inherent flexibility, which is confirmed by molecular simulations. Consequently, the encapsulation of LDS 722 into MgAPO-11 has led to an astonishing enhancement of the fluorescence with respect to the dye into MgAPO-5, with slightly larger cylindrical channels, and with respect to the dye in solution. Moreover, the perfect alignment of LDS 722 (dye with intrinsic nonlinear-optical properties) along the channels of MgAPO-11 has revealed attractive second-order nonlinear properties, such as second harmonic generation, proven through microscopy measurements in single crystals.
在本工作中，通过结晶包合方法将半菁染料LDS 722封装到MgAPO - 11铝磷酸盐的一维椭圆形纳米通道中。通过系统改变结晶条件对杂化材料的合成进行了优化，以获得适合光学应用的纯净大晶体（约20 μm×30 μm）。客体染料的分子尺寸与主体的孔尺寸之间的紧密匹配有利于染料形成刚性平面构象，限制了其固有的柔韧性，这一点得到了分子模拟的证实。因此，与封装在具有稍大圆柱形通道的MgAPO - 5中的染料以及溶液中的染料相比，将LDS 722封装到MgAPO - 11中导致荧光显著增强。此外，LDS 722（具有固有非线性光学性质的染料）沿MgAPO - 11通道的完美排列展现出了有吸引力的二阶非线性性质，如二次谐波产生，这通过单晶显微镜测量得到了证实。
