TY - JOUR
T1 - Electronic interplay on illuminated aqueous carbon nanohorn-porphyrin ensembles
AU - Pagona, Georgia
AU - Sandanayaka, Atula S.D.
AU - Araki, Yasuyuki
AU - Fan, Jing
AU - Tagmatarchis, Nikos
AU - Yudasaka, Masako
AU - Iijima, Sumio
AU - Ito, Osamu
PY - 2006/10/26
Y1 - 2006/10/26
N2 - Tetracationic water-soluble porphyrin (H2P4+) has been immobilized by π-π stacking interactions onto the skeleton of carbon nanohorns (CNH), without disrupting their π-electronic network. The stable aqueous solution of the CNH-H2P4+ nanoensemble was examined by both electron microscopy and spectroscopic techniques. The efficient fluorescence quenching of the H2P4+ moiety in the CNH-H2P4+ nanoensemble was probed by steady-state as well as time-resolved fluorescence emission spectroscopy, suggesting charge separation from the photoexcited H2P4+ to CNH. In the presence of methyl viologen dication (MV2+) and a hole trap, accumulation of the reduced species of methyl viologen was observed by the photoillumination of CNH-H2P4+, suggesting that the electron migration from the initially formed charge-separated state takes place. Transient absorption spectroscopy gave further insights on the transient species such as the charge-separated state (CNH.-)-(H 2P4+).+, which was consumed in the presence of MV2+ and hole shifter, leaving the reduced methyl viologen.
AB - Tetracationic water-soluble porphyrin (H2P4+) has been immobilized by π-π stacking interactions onto the skeleton of carbon nanohorns (CNH), without disrupting their π-electronic network. The stable aqueous solution of the CNH-H2P4+ nanoensemble was examined by both electron microscopy and spectroscopic techniques. The efficient fluorescence quenching of the H2P4+ moiety in the CNH-H2P4+ nanoensemble was probed by steady-state as well as time-resolved fluorescence emission spectroscopy, suggesting charge separation from the photoexcited H2P4+ to CNH. In the presence of methyl viologen dication (MV2+) and a hole trap, accumulation of the reduced species of methyl viologen was observed by the photoillumination of CNH-H2P4+, suggesting that the electron migration from the initially formed charge-separated state takes place. Transient absorption spectroscopy gave further insights on the transient species such as the charge-separated state (CNH.-)-(H 2P4+).+, which was consumed in the presence of MV2+ and hole shifter, leaving the reduced methyl viologen.
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U2 - 10.1021/jp064685m
DO - 10.1021/jp064685m
M3 - Article
C2 - 17048875
AN - SCOPUS:33751284699
SN - 1520-6106
VL - 110
SP - 20729
EP - 20732
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 42
ER -