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Abstract Plasmon decay is believed to play an essential role in inducing hot carrier transfer at the interfaces between plasmonic nanoparticles and semiconductor surfaces. In this work, we employ real-time time-dependent density functional theory (RT-TDDFT) simulation in the Wannier gauge to gain quantum-mechanical insights into the nonlinear dynamics of the plasmon decay in the Ag20nanoparticle at a semiconductor surface. The first-principles simulations show that the plasmon decay is more than two times faster when the Ag20nanoparticle is adsorbed on a hydrogen-terminated Si(111) surface, taking place within 100 femtoseconds of the plasmon excitation. Hot carrier transfer across the interface is observed as the plasmon decay takes place, and nearly 30% of holes are generated deep in the valence band of the semiconductor surface. The use of Wannier gauge in RT-TDDFT simulation is particularly convenient for gaining quantum-mechanical insights into non-equilibrium electron dynamics in complex heterogeneous systems.
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Structural Engineering of Semiconductor Nanoparticles by Conjugated Interfacial Bonds
Abstract Surface functionalization of semiconductor nanoparticles plays a significant role in the manipulation of the nanoparticle physicochemical properties and diverse applications. Conventional points of anchor involve mercapto, carboxyl and phenol moieties, forming largely nonconjugated interfacial linkages. In this personal account, we summarize recent progress in surface functionalization of semiconductor nanoparticles with olefin and acetylene derivatives, where the formation of conjugated interfacial bonds leads to ready manipulation of the nanoparticle optical and electronic properties, by using Si and TiO2nanoparticles as the illustrating examples. Finally, a perspective is included where the promises and challenges of structural engineering of semiconductor nanoparicles are highlighted.
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- Award ID(s):
- 1710408
- PAR ID:
- 10131394
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- The Chemical Record
- Volume:
- 20
- Issue:
- 1
- ISSN:
- 1527-8999
- Page Range / eLocation ID:
- p. 41-50
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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