稀土三酞菁夹心化合物混合LB膜的研究

Study on Mixed LB Films of Triple-decker Sandwich RareEarth Phthalocyaninato Complex

将不对称三明治型夹心化合物(Pc)Dy[Pc(OC8H17)8]Dy[Pc(OC8H17)8]与硬脂酸混合成膜,表面压-面积(π-A)曲线表明形成了稳定的单层膜,由透射电子显微镜(TEM)观察,表明硬脂酸的加入有效地改善了分子的聚集行为,分子形成了取向高度有序的结构。用紫外-可见光谱、偏振紫外可见光谱、低角X射线衍射等对LB膜进行了研究,发现该取代稀土三酞菁分子在气/液界面上长链向上伸展,分子之间均以面对面(face-to-face)排列,以一边接触(edge-on)方式取向,大环平面与基片夹角约为52°,每层厚度为2.41nm。

Monolayers and Langmuir-Blodgett(LB) films of the sandwich-type complex [PcDyPc(OC8H17)(8)DyPc(OC8H17)(8)] and its mixture with stearic acid (SA) have been studied. Surface pressure-area isotherm indicates that a stable monolayer was formed. The monolayer morphology was investigated by transmission electron microscopy (TEM). The aggregates of the (Pc)Dy[Pc(OC8H17)(8)]Dy[Pc(OC8H17)(8)] molecules was dispersed effectively by SA molecules as observed from TEM. Columnar domains were well ordered with the width of ca 40 nm and the length of several hundreds of nanometers as seen in the micrograph. The monolayer of the complex mixed with SA was successfully deposited on hydrophobic substrates by Langmuir-Blodgett method. The UV-Vis absorption peaks of LB film were red shifted compared with those in solution, indicating the formation of J-aggregates. The orientation angle of the phthalocyanine ring with respect to the substrate was evaluated to be ca 52degrees according to the Polarized UV-Vis spectra. The low-angle X-ray diffraction pattern showed a periodic distance of 2.41 nm for the mixed LB film. Based on all these considerations, a schematic arrangement of the complex molecules in LB films was suggested.