TY - GEN
T1 - Ultrafast IR spectroscopic study of free carrier formation and charge trapping in organic photovoltaic polymer blends
AU - Pensack, Ryan D.
AU - Banyas, Kyle M.
AU - Asbury, John B.
PY - 2009
Y1 - 2009
N2 - Photoinduced charge separation, charge recombination, and trapping in polymer blend organic photovoltaic materials are examined using ultrafast 2D IR and vis-IR spectroscopy in conjunction with transient photocurrent techniques. Native vibrational modes of the functionalized fullerene, PCBM, are probed as reporters of the charge carrier dynamics. Following a free carrier formation process that occurs on a surprisingly fast picosecond time scale, charge carriers become trapped in poly(p-phenylenevinylene) (PPV)-based OPV materials but are not readily trapped in polythiophene (PT)-based materials. The trapping process results in the formation of distinct vibrational features that are not present in the PT-based materials. Although the origin of the distinct trapping characteristics remains unclear, they help rationalize the qualitatively different bimolecular charge recombination behavior that has been observed in PPV-based versus PT-based OPV materials. 2D IR spectroelectrochemical investigations of trapped charges may provide a means to elucidate the structures of the traps in PPV-based materials.
AB - Photoinduced charge separation, charge recombination, and trapping in polymer blend organic photovoltaic materials are examined using ultrafast 2D IR and vis-IR spectroscopy in conjunction with transient photocurrent techniques. Native vibrational modes of the functionalized fullerene, PCBM, are probed as reporters of the charge carrier dynamics. Following a free carrier formation process that occurs on a surprisingly fast picosecond time scale, charge carriers become trapped in poly(p-phenylenevinylene) (PPV)-based OPV materials but are not readily trapped in polythiophene (PT)-based materials. The trapping process results in the formation of distinct vibrational features that are not present in the PT-based materials. Although the origin of the distinct trapping characteristics remains unclear, they help rationalize the qualitatively different bimolecular charge recombination behavior that has been observed in PPV-based versus PT-based OPV materials. 2D IR spectroelectrochemical investigations of trapped charges may provide a means to elucidate the structures of the traps in PPV-based materials.
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M3 - Conference contribution
AN - SCOPUS:78649509558
SN - 9780841224414
T3 - ACS National Meeting Book of Abstracts
BT - American Chemical Society - 237th National Meeting and Exposition, ACS 2009, Abstracts of Scientific Papers
T2 - 237th National Meeting and Exposition of the American Chemical Society, ACS 2009
Y2 - 22 March 2009 through 26 March 2009
ER -