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Both noble metal nanoparticles (NPs) and chalcopyrite (CuFeS2) nanocrystals (NCs) provide resonant absorption in the visible, albeit through different mechanisms. Coherent oscillations of free conduction band electrons give rise to localized plasmons in noble metal NPs, whereas collective oscillations of bound electrons are responsible for quasistatic resonances in CuFeS2 NCs. This manuscript reviews the photophysical and photocatalytic properties of both noble metal and chalcopyrite nanostructures as well as direct and indirect charge and energy transfer processes in hybrid structures containing noble metal NPs and either semiconductor NCs or molecular photosensitizers or photocatalysts. CuFeS2 NCs share structural similarities with conventional semiconductor NCs, but the availability of collective charge oscillations in the visible facilitates a resonant coupling to localized plasmons in NPs. Hybrid nanostructures containing both metal and chalcopyrite building blocks are examined as a platform for wavelength-dependent charge and energy transfer and bifunctional reactivity for enhanced plasmonic photocatalysis.
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Plasmonic Resonant Intercluster Coulombic Decay
Light-induced energy confinement in nanoclusters via plasmon excitations influences applications in nanophotonics, photocatalysis, and the design of controlled slow electron sources. The resonant decay of these excitations through the cluster’s ionization continuum provides a unique probe of the collective electronic behavior. However, the transfer of a part of this decay amplitude to the continuum of a second conjugated cluster may offer control and efficacy in sharing the energy nonlocally to instigate remote collective events.With the example of a spherically nested dimer Na20@C240 of two plasmonic systems we find that such a transfer is possible through the resonant intercluster Coulombic decay (RICD) as a fundamental process. This plasmonic RICD signal can be experimentally detected by the photoelectron velocity map imaging technique.
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- PAR ID:
- 10522319
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review Letters
- Volume:
- 130
- Issue:
- 23
- ISSN:
- 0031-9007
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1103/PhysRevLett.130.233201
