Photoinduced Charge Separation and Charge Recombination in [60]Fullerene-(Benzothiadiazole-Triphenylamine) Based Dyad in Polar Solvents
摘要:
The molecular dyad C-60-(BTD-TPA) consisting of an electron donor triphenylamine-appended 2,1,3-benzothiadiazole chromophore (BTD-TPA) unit covalently linked to an electron acceptor [60]fullerene has been synthesized. The photoinduced electron transfer in C-60-(BTD-TPA) has been studied in polar and nonpolar solvents using time-resolved transient absorption and fluorescence measurements. By fluorescence lifetime measurements in picosecond time regions, the excitation of the C-60 moiety leads to the formation Of C-60(.-)-(BTD-TPA)(.+) efficiently via the singlet excited state of the C-60 moiety. Excitation of the BTD-TPA moiety leads to initial energy transfer to C-1(60)*-(BTD-TPA), from which electron transfer occurs to form C-60(.-)-(BTD-TPA)(.+). In the nanosecond time region, C-60(.-)-(BTD-TPA)(.+) in which the radical cation (hole) delocalizes in the BTD-TPA moiety is persistent for 690 ns in DMF at room temperature. From the temperature dependence of the charge-recombination rate constants, which gave the Marcus parameters, we attempted to reveal the origins of long persistent C-60(.-)-(BTD-TPA)(.+) in DMF.
Photoinduced Charge Separation and Charge Recombination in [60]Fullerene-(Benzothiadiazole-Triphenylamine) Based Dyad in Polar Solvents
摘要:
The molecular dyad C-60-(BTD-TPA) consisting of an electron donor triphenylamine-appended 2,1,3-benzothiadiazole chromophore (BTD-TPA) unit covalently linked to an electron acceptor [60]fullerene has been synthesized. The photoinduced electron transfer in C-60-(BTD-TPA) has been studied in polar and nonpolar solvents using time-resolved transient absorption and fluorescence measurements. By fluorescence lifetime measurements in picosecond time regions, the excitation of the C-60 moiety leads to the formation Of C-60(.-)-(BTD-TPA)(.+) efficiently via the singlet excited state of the C-60 moiety. Excitation of the BTD-TPA moiety leads to initial energy transfer to C-1(60)*-(BTD-TPA), from which electron transfer occurs to form C-60(.-)-(BTD-TPA)(.+). In the nanosecond time region, C-60(.-)-(BTD-TPA)(.+) in which the radical cation (hole) delocalizes in the BTD-TPA moiety is persistent for 690 ns in DMF at room temperature. From the temperature dependence of the charge-recombination rate constants, which gave the Marcus parameters, we attempted to reveal the origins of long persistent C-60(.-)-(BTD-TPA)(.+) in DMF.
Photoinduced Charge Separation and Charge Recombination in [60]Fullerene-(Benzothiadiazole-Triphenylamine) Based Dyad in Polar Solvents
作者:Atula S. D. Sandanayaka、Kyohei Matsukawa、Tsutomu Ishi-i、Shuntaro Mataka、Yasuyuki Araki、Osamu Ito
DOI:10.1021/jp045534r
日期:2004.12.1
The molecular dyad C-60-(BTD-TPA) consisting of an electron donor triphenylamine-appended 2,1,3-benzothiadiazole chromophore (BTD-TPA) unit covalently linked to an electron acceptor [60]fullerene has been synthesized. The photoinduced electron transfer in C-60-(BTD-TPA) has been studied in polar and nonpolar solvents using time-resolved transient absorption and fluorescence measurements. By fluorescence lifetime measurements in picosecond time regions, the excitation of the C-60 moiety leads to the formation Of C-60(.-)-(BTD-TPA)(.+) efficiently via the singlet excited state of the C-60 moiety. Excitation of the BTD-TPA moiety leads to initial energy transfer to C-1(60)*-(BTD-TPA), from which electron transfer occurs to form C-60(.-)-(BTD-TPA)(.+). In the nanosecond time region, C-60(.-)-(BTD-TPA)(.+) in which the radical cation (hole) delocalizes in the BTD-TPA moiety is persistent for 690 ns in DMF at room temperature. From the temperature dependence of the charge-recombination rate constants, which gave the Marcus parameters, we attempted to reveal the origins of long persistent C-60(.-)-(BTD-TPA)(.+) in DMF.