二茂铁-酞菁-富勒烯超分子三元体系的构筑及光物理和电化学性质

采用富勒吡咯烷衍生物中的吡啶或咪唑基与二茂铁修饰的金属酞菁轴向配位构筑了二茂铁-酞菁-富勒烯超分子三元体系,通过紫外-可见光谱滴定法测定了其配位稳定性(Kassoc约为8.58×104L/mol).稳态和时间分辨荧光光谱研究结果表明,在该超分子三元体系中发生了快速的光诱导电子转移(kCS约为109s-1),并具有较高的电荷分离态量子产率(ФCS=0.88).循环伏安法数据表明,其电荷分离驱动力ΔGcs为负值(-0.60 eV),说明酞菁和富勒烯之间容易形成电荷分离态.

Construction, Photophysical and Electrochemical Studies on Ferrocene-phthalocyanine-fullerene Supramolecular Triads

Much attention has been paid recently to the studies on photoinduced electron transfer in donor acceptor systems mainly to develop artificial photosynthetic systems and molecular optoelectronic devices. Several covalent and supramolecular phthalocyanine-fullerene systems have been prepared for this purpose, but only a few triads have been reported to date. In this article, ferrocene-phthalocyanine-fullerene supramolecular triads were constructed with pyridine- or imidazole-appended fulleropyrrolidine and covalently linked zinc phthalocyanine-ferrocene dyad via axial coordination. The stablilities of the triads(Kassoc=8.58×104 L/mol) were studied by optical absorption methods. Steady-state and time-resolved fluorescence measurements suggested that the occurrence of efficient photoinduced electron transfer(kCS =109 s-1) from excited phthalocyanine to fullerene entity in the triads with high charge-separation quantum yields(ФCS =0.88). The redox potentials were determined by cyclic voltammetric, and the driving forces(ΔGCS =-0.60 eV) were estimated to be exothermic, which favored the forming of charge-separation state.