Silicon-phthalocyanine-cored fullerene dendrimers: synthesis and prolonged charge-separated states with dendrimer generations.
Silicon-phthalocyanine-cored fullerodendrimers with up to eight fullerene substituents (SiPc-n C(60); n=2, 4, and 8) have been synthesized. Photophysical properties of newly synthesized SiPc-n C(60) have been investigated by time-resolved fluorescence and transient absorption analysis with pulsed laser light. Laser photolysis measurements suggest the occurrence of a charge-separation process from (1)SiPc* to the C(60) subunits. The nanosecond transient absorption spectra in the near-IR region indicate that the lifetimes of the formed radical ion pairs are prolonged on the order of SiPc-8 C(60)>SiPc-4 C(60)>SiPc-2 C(60), which may be related to the electron migration among the C(60) subunits. The usefulness of SiPc-n C(60) as light-harvesting systems, evaluated as a ratio of the rates of charge recombination to those of charge separation, increases markedly with the dendrimer generation.
El-Khouly
Mohamed E
ME
Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan.
Kang
Eui Su
ES
Kay
Kwang-Yol
KY
Choi
Chan Soo
CS
Aaraki
Yasuyuki
Y
Ito
Osamu
O
D000042:Absorption; D050091:Dendrimers / Q000138:chemical synthesis*; D037741:Fullerenes / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D007834:Lasers; D008956:Models, Chemical; D017646:Organosilicon Compounds / Q000737:chemistry*; D010777:Photochemistry; D010782:Photolysis; D013057:Spectrum Analysis
D050091:Dendrimers; D037741:Fullerenes; D007211:Indoles; D017646:Organosilicon Compounds; C082854:silicon phthalocyanine