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Abstract Plasmon‐mediated carrier transfer (PMCT) at metal–semiconductor heterojunctions has been extensively exploited to drive photochemical reactions, offering intriguing opportunities for solar photocatalysis. However, to date, most studies have been conducted using noble metals. Inexpensive materials capable of generating and transferring hot carriers for photocatalysis via PMCT have been rarely explored. Here, we demonstrate that the plasmon excitation of nickel induces the transfer of both hot electrons and holes from Ni to TiO2in a rationally designed Ni–TiO2heterostructure. Furthermore, it is discovered that the transferred hot electrons either occupy oxygen vacancies (VO) or produce Ti3+on TiO2, while the transferred hot holes are located on surface oxygens at TiO2. Moreover, the transferred hot electrons are identified to play a primary role in driving the degradation of methylene blue (MB). Taken together, our results validate Ni as a promising low‐cost plasmonic material for prompting visible‐light photochemical reactions.
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This content will become publicly available on November 11, 2025
Hot carrier transfer from plasmon decay in Ag 20 at H–Si(111) surface: real-time TDDFT simulation in Wannier gauge
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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- Award ID(s):
- 1954894
- PAR ID:
- 10571585
- Publisher / Repository:
- Institute of Physics Publishing
- Date Published:
- Journal Name:
- Journal of Physics: Condensed Matter
- Volume:
- 37
- Issue:
- 4
- ISSN:
- 0953-8984
- Page Range / eLocation ID:
- 045502
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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