Anomalous photoluminescence Stokes shift in CdSe nanoparticle and carbon nanotube hybrids
نویسندگان
چکیده
A very large decrease in the Stokes shift in CdSe nanoparticle (NP) photoluminescence is seen from hybrid materials in which the NPs are attached to single-walled carbon nanotubes after pyridine treatment relative to unbound NPs capped by pyridine. This is observed particularly for very small NPs, for hybrids composed of core-only and core-shell NPs, and for hybrids made with bundles of mixtures of semiconducting and metallic nanotubes or with semiconducting nanotubes only and is likely due to fast Förster resonance energy transfer (FRET) from the NPs to the nanotubes. A simple model demonstrates the plausibility of the hot luminescence explanation of this decreased Stokes shift.
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