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Narrow-band absorption-enhanced quantum dot/J-aggregate conjugates.

ABSTRACT: We report narrow-band absorption enhancement of semiconductor nanocrystals via Förster resonance energy transfer from cyanine J-aggregates. These J-aggregated dyes associate electrostatically with short quantum-dot (QD) surface ligands in solution. Energy transfer efficiencies approach unity for this light sensitization and result in a 5-fold enhancement in the QD excitation near the J-aggregate absorption maximum. Because a thin layer of J-aggregates attenuates the same amount of light (at peak absorbance) as a far thicker film of monomer dye, these absorption-enhanced materials may have applications in light-sensitizing applications such as photodetection and optical down-conversion.

SUBMITTER: Walker BJ

PROVIDER: S-EPMC3351077 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Narrow-band absorption-enhanced quantum dot/J-aggregate conjugates.

Walker Brian J BJ Nair Gautham P GP Marshall Lisa F LF Bulović Vladimir V Bawendi Moungi G MG

Journal of the American Chemical Society 20090701 28

We report narrow-band absorption enhancement of semiconductor nanocrystals via Förster resonance energy transfer from cyanine J-aggregates. These J-aggregated dyes associate electrostatically with short quantum-dot (QD) surface ligands in solution. Energy transfer efficiencies approach unity for this light sensitization and result in a 5-fold enhancement in the QD excitation near the J-aggregate absorption maximum. Because a thin layer of J-aggregates attenuates the same amount of light (at peak ...[more]

PMID: 19548672

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