Halide-Metal Complexes at Plasmonic Interfaces Create New Decay Pathways for Plasmons and Excited Molecules

Stefancu, Andrei; Biro, Oana M.; Todor-Boer, Otto; Botiz, Ioan; Cortes, Emiliano und Leopold, Nicolae (2022): Halide-Metal Complexes at Plasmonic Interfaces Create New Decay Pathways for Plasmons and Excited Molecules. In: ACS Photonics, Bd. 9, Nr. 3: S. 895-904

Abstract

We show that by modifying the chemical interface of silver nanoparticles (AgNPs) with halide ions, it is possible to tune the total decay rate of adsorbed excited molecules and the plasmon damping rate. Through single-molecule surface-enhanced Raman scattering and surface-enhanced fluorescence enhancement factors of crystal violet (CV) and rhodamine 6G (R6G), we show that I--modified AgNPs (AgNPspl) and Br--modified AgNPs (AgNPs@Br) lead to an increase in the total decay rate of excited CV and R6G by a factor between similar to 1.6-2.6, compared to Cl--modified AgNPs (AgNPs@CO. In addition, we found that the chemical interface damping, which characterizes the plasmon resonance decay into surface states, is stronger on AgNPs@I and AgNPs@Br when compared to AgNPs@Cl. These results point toward the formation of metal-halide surface complexes. These new interfacial states can accept electrons from both excited molecular orbitals and surface plasmon excitations, completely altering the electronic dynamics and reactivity of plasmonic interfaces.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 2330-4022
• Sprache: Englisch
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 390776260