Plasmon-Modulated Excitation-Dependent Fluorescence from Activated CTAB Molecules Strongly Coupled to Gold Nanoparticles

Abstract

Excitation-dependent fluorophores (EDFs) have been attracted increasing attention owing to their high tunability of emissions and prospective applications ranging from multicolor patterning to bio-imaging. Here, we report tunable fluorescence with quenching dip induced by strong coupling of exciton and plasmon in the hybrid nanostructure of CTAB* EDFs and gold nanoparticles (AuNPs). The quenching dip in the fluorescence spectrum is tuned by adjusting excitation wavelength as well as plasmon resonance and concentration of AuNPs. The observed excitation-dependent emission spectra with quenching dip are theoretically reproduced and revealed to be induced by resonant energy transfer from multilevel EDFs with wider width channels to plasmonic AuNPs. These findings provide a new approach to prepare EDF molecules and a strategy to modulate fluorescence spectrum via exciton-to-plasmon energy transfer.

Towards the Development of Antioxidant Cerium Oxide Nanoparticles for Biomedical Applications: Controlling the Properties by Tuning Synthesis Conditions

“…This evidence can also be the cause of a peak splitting in the fluorescence spectrum. The presence of this peak splitting could be due to Rabi splitting phenomena, which were until now observed for metallic NPs (i.e., Au or Ag) and, only partially, for some semiconductors [ 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 ]. In our case, the splitting was observed only for CeO 2 _OC_150 samples and could be related to the presence of oxygen vacancies on the nanoparticles surface (intraparticle voids) and/or to the formation of cluster (interparticle voids), that are indeed observed by means of both TEM and DLS.…”

Plasmon-Modulated Excitation-Dependent Fluorescence and Antimicrobial Activities of Silver and Gold Nanoparticles Prepared with Eugenia unifloraL. extracts

“…To obtain this equation, the authors have assumed the same radiative/nonradiative rate and the same spectral width for all intermediate states. This equation demonstrates that the uorescence peak wavelength increases with the excitation wavelength [34].…”

“…A theoretical model described by Ding et al [34] explained plasmon-modulated excitation-dependent uorescence strongly coupled to gold nanoparticles. By their theory, the uorophores (without NPs, in their case activated hexadecyltrimethyl ammonium bromide-CTAB*) present long lifetime multilevel states due to the surface states from the functional group.…”

“…Another intriguing effect is plasmon-modulated excitationdependent uorescence (EDF). The emission peak of EDFs red-shifts as the excitation wavelength increases, which is usually explained as the red-edge effect in the multilevels [34] .…”

V2O5, CeO2 and Their MWCNTs Nanocomposites Modified for the Removal of Kerosene from Water

“…In mixed composites, the constituent V2O5 orthorhombic crystalline structure dominates over the CeO2 equivalent. Furthermore, the presence of some impurities was observed at 18.20° and 24.20° 2θ originating from the preparation step [38]. The oxidized MWCNTs, V/MWCNTs, Ce/MWCNTs, and V:Ce/MWCNTs samples were treated at 200 °C.…”