New coumarin-[60]fullerene dyads connected by an alkynyl linkage: Synthesis and fluorescence studies. Evidence for efficient singlet–singlet energy transfer
作者:Susana Nascimento、Alexander Fedorov、Maria J. Brites、Mário N. Berberan-Santos
DOI:10.1016/j.dyepig.2014.11.005
日期:2015.3
coumarin and C60 moieties. In both dyads and in all solvents, a strong quenching of the coumarin emission by C60 was observed. It mainly results from a fast and efficient singlet–singlet resonance energy transfer from the coumarin moiety to the C60 moiety, but an electron transfer contribution, enhanced in polar solvents, also exists. In toluene, the fluorescence emission of the fullerene moiety is increased
通过1,3-偶极环加成反应合成了两个新的香豆素-[60]富勒烯二联体,其中炔基将C 60与香豆素共价连接,并进行了光谱表征。在室温下研究了它们在非极性(甲苯)和极性(THF和苄腈)溶剂中的光物理性质,揭示了香豆素与C 60部分之间激发态相互作用的性质和极性依赖性。在二重体和所有溶剂中,均观察到C 60对香豆素发射的强烈淬灭。它主要是由于从香豆素部分到C 60的快速有效的单重态-单重共振能量转移。也存在一部分,但是在极性溶剂中也增强了电子转移的贡献。在甲苯中,富勒烯部分的荧光发射通过非辐射能量转移过程而增加,这主要是通过偶极子-偶极子(FRET)机理发生的。在极性溶剂(THF和苄腈)中,从基态香豆素到激发富勒烯的快速电子转移非常重要,这取决于二联体,导致富勒烯发射的部分或完全淬灭。