Croatica Chemica Acta, Vol. 97 No. 2, 2024.
Original scientific paper
https://doi.org/10.5562/cca4107
Structural Characterization of 4-Aminothiophenol in Silver and Gold Colloids using Surface-Enhanced Raman Scattering
Anastazija Ratkajec
; Department of Chemistry, Faculty of Science, University of Zagreb, Zagreb, Croatia
Adriana Kenđel
orcid.org/0000-0001-8820-649X
; Department of Chemistry, Faculty of Science, University of Zagreb, Zagreb, Croatia
*
* Corresponding author.
Supplements: cca4107_supplement.pdf
Abstract
Surface-enhanced Raman scattering (SERS) spectroscopy was used for the structural characterization of 4-aminothiophenol molecules in silver and gold colloids. During the SERS experiment on silver nanoparticles, structural changes occurred in the molecules adsorbed on the metal surface. The observed changes were associated with the dimerization process of 4-aminothiophenol under the influence of laser radiation, leading to the formation of 4,4'-dimercaptoazobenzene. The use of excitation at 532 nm with radiation power that is quite low for traditional SERS measurements proved to be optimal for catalyzing the dimerization process, while using laser excitation at 785 nm less stimulated dimerization of the studied compound. Unlike silver, gold nanospheres proved to be less suitable substrates for catalyzing the dimerization process under the chosen experimental conditions. Unmodified, freshly prepared silver colloid proved to be an adequate substrate for stimulating the dimerization of 4-aminothiophenol during classical SERS measurements, even when an excitation radiation power of less than 5 mW was used.
Keywords
surface-enhanced Raman scattering; 4-aminothiophenol; dimerization; 4,4'-dimercaptoazobenzene; silver; gold; colloid
Hrčak ID:
322440
URI
Publication date:
16.11.2024.
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