10.1021/acs.langmuir.7b00126.s001
Markéta Prusková
Markéta
Prusková
Veronika Sutrová
Veronika
Sutrová
Miroslav Šlouf
Miroslav
Šlouf
Blanka Vlčková
Blanka
Vlčková
Jiří Vohlídal
Jiří
Vohlídal
Ivana Šloufová
Ivana
Šloufová
Arrays of Ag and Au Nanoparticles with Terpyridine-
and Thiophene-Based Ligands: Morphology and Optical Responses
American Chemical Society
2017
excitation wavelength
nanoparticulate arrays
metal NPs
antibonding orbitals
surface plasmon excitations
SPE spectra
interparticle distances
Thiophene-Based Ligands
SERS
photoinduced CT
interparticle linkers
NP hydrosol
molecules act
surface plasmon extinction
0 surface
0 adsorption sites
Photoinduced charge transfer
TEM
Optical Responses
interparticle distance
transmission electron microscopy
NP islands
oligomers molecules
marker band evidence
Ag NPs
image analysis
0 surface complexes
tpy
2017-04-10 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Arrays_of_Ag_and_Au_Nanoparticles_with_Terpyridine-_and_Thiophene-Based_Ligands_Morphology_and_Optical_Responses/4891766
The
assembly of Ag and Au nanoparticles (NPs) into nanoparticulate
arrays mediated by terpyridine (tpy), 4′-(2-thienyl)terpyridine
(T-<i>tpy</i>), and short α,ω-bis(<i>tpy</i>)oligothiophene ligands has been accomplished at the interface between
the Ag or Au NP hydrosol and a solution of the molecular species in
dichloromethane. The relationship between the morphology and the optical
responses of the arrays has been investigated by advanced methods
of TEM (transmission electron microscopy) image analysis and surface
plasmon extinction (SPE) spectra. It has been established that the
size of islands of closely spaced NPs rather than the average interparticle
distance affects the extent of delocalization of the surface plasmon
excitations and thus also the SPE spectra. Furthermore, the structure
of surface–adsorbate complexes formed in these arrays has been
investigated by SERS spectral measurements carried out as a function
of the excitation wavelength. Photoinduced charge transfer (CT) transitions
from the neutral Ag<sub>s</sub><sup>0</sup> and Au<sub>s</sub><sup>0</sup> adsorption sites on metal NPs to antibonding orbitals of the adsorbates
have been identified for Ag/tpy, Ag/T-<i>tpy</i>, Au/tpy,
and Au/T-<i>tpy</i> nanoparticulate arrays. Although the
surface–adsorbate complexes displaying a photoinduced CT are
known for Ag NPs, the Au<sub>s</sub><sup>0</sup> surface complexes with this CT are newly reported. Bis(<i>tpy</i>)oligothiophenes were found to be attached to both Ag
and Au NPs via the <i>tpy</i> group(s). The match between
the interparticle distances within the NP islands and the lengths
of the oligomers molecules indicates that the molecules act as interparticle
linkers. In this case, unequivocal spectral marker band evidence of
the Ag<sub>s</sub><sup>0</sup> as
well as Au<sub>s</sub><sup>0</sup> surface complex formation has not been obtained.