Photoinduced charge-separation and charge-recombination processes of oligo(thienyleneethynyl)-fullerene dyad molecules
Photoinduced charge-separation and charge-recombination processes of oligo(thienyleneethynyl)-fullerene dyad molecules
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DOI：
10.1246/bcsj.79.1860
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发表时间：
2006-12-15
影响因子：
4
通讯作者：
Otsubo, Tetsuo
中科院分区：
文献类型：
--
作者：
Fujitsuka, Mamoru;Makinoshima, Takashi;Otsubo, Tetsuo
用亚皮秒激光闪光光解瞬态吸收光谱研究了两个系列的寡（噻吩乙炔基）-富勒烯二元体（简称nTE-C-60）的光诱导电荷分离和复合过程，其中nTE部分具有线性（n α TE）和锯齿形（n β TE）结构.基于瞬态吸收光谱，在nTE-C-60中发生电荷分离，速率常数为10（11）s（-1）的量级，表明几乎定量的电荷分离。对于所有nTE-C_（60）二元体，在甲苯中的电荷分离速率常数均大于在苯甲腈中的，表明电荷分离过程是溶剂控制的绝热过程。另一方面，电荷复合过程回到基态时的速率常数为10（8）-10（9）s（-1）。尽管电荷复合的自由能变化相似，但n α TE-C-60的电荷复合速率比具有锯齿形结构的n β TE-C-60快。
Photoinduced charge-separation and -recombination processes in two series of oligo(thienyleneethynyl)-fullerene dyads (abbreviated as nTE-C-60), in which the nTE moiety has a linear (n alpha TE) or zigzag structure (n beta TE), have been investigated by using transient absorption spectroscopy with sub-picosecond laser flash photolysis. Based on the transient absorption spectra, charge separation occurs in nTE-C-60 with the rate constants on the order of 10(11) s(-1), indicating almost quantitative charge separation. For all nTE-C60 dyads, the charge-separation rate-ccnstants in toluene were larger than those in benzonitrile, suggesting that the charge-separation process is a solvent-controlled adiabatic process. On the other hand, the charge-recombination processes going back to the ground state occurred with the rate constants on the order of 10(8)-10(9) s(-1). The charge-recombination rate of n alpha TE-C-60 was faster than that in n beta TE-C-60 with a zigzag structure, in spite of similar free energy change for the charge recombination.