title: Characterization and surface-enhanced Raman spectral probing of silver hydrosols prepared by two-wavelength laser ablation and fragmentation.
abstract: A four step Ag foil laser ablation-Ag nanoparticle fragmentation procedure in ultrapure water was carried out both under argon and in air. Pulses of a high power Nd/YAG laser were used for laser ablation (1064 nm) and for the three step Ag hydrosol treatment in the absence of Ag foil in the sequence 1064-532-1064 nm. Transmission electron microscopy (TEM) and surface plasmon (SP) extinction spectra provide evidence of Ag nanoparticle fragmentation in the second and third step of the procedure carried out under argon. While polydispersity of Ag hydrosol increases in the second step, both the polydispersity and the mean size of the nanoparticles are reduced in the third step. Qualitative and quantitative surface-enhanced Raman scattering (SERS)/surface-enhanced resonance Raman scattering (SERRS) spectral probing of systems with Ag hydrosols and the selected adsorbates at 514.5 nm excitation shows that Ag hydrosols obtained in the second step of the preparation procedure carried out in air are the most suitable substrates for SERS/SERRS experiments performed at this excitation wavelength.
authors.affiliation: Department of Physical and Macromolecular Chemistry, Charles University, Hlavova 2030, CZ-12840 Prague 2, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Smejkal
authors.forename: Karolína
authors.initials: K
authors.lastname: Sisková
authors.forename: Blanka
authors.initials: B
authors.lastname: Vlcková
authors.forename: Jirí
authors.initials: J
authors.lastname: Pfleger
authors.forename: Ivana
authors.initials: I
authors.lastname: Sloufová
authors.forename: Miroslav
authors.initials: M
authors.lastname: Slouf
authors.forename: Peter
authors.initials: P
authors.lastname: Mojzes
mesh_terms: D018030:Silver Compounds / Q000737:chemistry*; D013059:Spectrum Analysis, Raman
chemical_list: D018030:Silver Compounds