酞菁配合物掺杂对芘/硅树脂材料光学-氧猝灭特性的影响

基于氧对荧光的猝灭作用, 含荧光探针的高分子复合物已成为定量测定氧浓度或氧分压的新型功能材料. 本工作将酞菁及酞菁的氯铝、镁、硅和铜配位化合物掺杂在芘/聚二甲基硅氧烷光学-氧压传感材料中, 观察了它们的氧猝灭光物理作用. 结果表明, 酞菁配合物掺杂对氧猝灭显示良好的线性响应; 酞菁的硅和铜配合物可有效地增加氧猝灭灵敏度; 而酞菁氯铝降低了氧猝灭的温度系数. 这与发射谱上芘的I₃/I₁值, 芘的微环境极性相对应, 并可归因为芘与酞菁配合物的电子转移性质对荧光猝灭的影响, 以及共轭结构的稳定化和均质化作用.

Effect of Phthalocyanine Coordination Compound Doping on the Luminescent Oxygen Quenching of Pyrene/polysilicone Coatings

Polymer films containing luminescent dyes are widely used in oxygen sensors. In this work, metal-free phthalocyanine (Pc) and several Pc coordination compounds, including Mg-Pc, AlCl-Pc, Si(OH)₂-Pc and Cu-Pc, were individually doped into pyrene/polysilicone coatings and then their luminescent oxygen quenching behavior was compared to that of dope-free one. It was experimentally observed that the doping of all the Pc coordination compounds into the coatings showed excellent Stern-Volmer plot linearity, the coatings with Cu-Pc and Si(OH)₂-Pc resulted in the enhancement of pressure sensitivity, and AlCl-Pc doped one presented the lowest temperature dependence for luminescent oxygen quenching. Those correspond to the micro-environmental polarity of pyrene chromophors in the film, which is proved by the variety of their emission intensity ratio values of I₃/I₁. Furthermore, this behavior is associated with the fluorescence quenching due to the increased spin-orbit interaction between the ions and rings, which considerably reduce the fluorescence intensity by converting them to non-radiative intersystem crossing. Also, the electronic transfer of a planar aromatic structure could be attributed to the increased stability between the dye and dope molecules.