Plasmonic hot‐electron‐assisted control of emission intensities and dynamics of CdSe/ZnS and infrared PbS quantum dots are studied. This is done by exploring the impact of Au/Si and Ag/Si Schottky junctions on the decay rates of such quantum dots when these junctions are placed in close vicinity of a Si/Al oxide charge barrier, forming metal‐oxide plasmonic metafilms. Such structures are used to investigate how metal‐dependent distributions of hot electrons and their capture via Schottky junctions can lead to suppression of the defect environments of quantum dots, offering a novel platform wherein off‐resonant (non‐Purcell) plasmonic processes are used to control exciton dynamics. These results show that Ag metafilms can enhance the emission of CdSe/ZnS quantum dots and elongate their lifetimes more than Au metafilms. This highlights the more efficient nature of Ag/Si Schottky junctions for hot electron excitation and capture. These results also show that such junctions can significantly suppress the nonradiative decay rates of PbS quantum dots at frequencies far from the plasmon resonances. These results demonstrate a field‐effect passivation of quantum dot defects via entrapment of hot electrons and control of emission intensities and dynamics of quantum dots via the nearly frequency‐independent electrostatic field of such electrons.
- Award ID(s):
- 1804412
- PAR ID:
- 10173586
- Date Published:
- Journal Name:
- Journal of Materials Chemistry C
- Volume:
- 7
- Issue:
- 47
- ISSN:
- 2050-7526
- Page Range / eLocation ID:
- 14788 to 14797
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/C9TC05150C
