Photoinduced charge separation reactions of J-aggregates coated on silver nanoparticles.
The photochemistry of cyanine J-aggregates on the surface of colloidal Ag nanoparticles is reported. The photochemistry is initiated through ultrafast photoexcitation of the plasmon band in Ag nanoparticles, producing an enhanced near-field that interacts with the J-aggregate monolayer. Through transient absorption spectroscopy, we show that photoexcitation of the plasmon in Ag nanoparticles leads to exciton dynamics that differ strongly from J-aggregates alone or for J-aggregate monolayers on bulk metal surfaces. Specifically, charge-separated states with a lifetime of 300 ps between the J-aggregate and Ag colloid are formed. The reduction of the Ag nanoparticles is shown to be a multielectron process.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- DE-AC02-06CH11357
- OSTI ID:
- 949427
- Report Number(s):
- ANL/CHM/JA-40824; JACSAT; TRN: US1003526
- Journal Information:
- J. Am. Chem. Soc., Vol. 124, Issue 17 ; May 1, 2002; ISSN 0002-7863
- Country of Publication:
- United States
- Language:
- ENGLISH
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