Berlin 2024 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 39: Poster: Metal Substrates
O 39.3: Poster
Dienstag, 19. März 2024, 18:00–20:00, Poster D
Optimizing a Surfactant-Free Silver Substrate for Surface-Enhanced Raman Spectroscopy — •Georgiana Ion, Stefania D Iancu, and Nicolae Leopold — Faculty of Physics, Babes-Bolyai University, 400084, Cluj-Napoca, Romania
Surface-Enhanced Raman Spectroscopy (SERS) relies on the adsorption of analytes to metallic nanoparticles, such as silver, a process often impeded by surfactants. This study introduces a straightforward and efficient method to obtain a surfactant-free SERS-active substrate, facilitating prompt analyte adsorption.
Citrate-capped silver nanoparticles (AgNPs) were concentrated, dried on a glass slide, and exposed to an ozone-rich environment (UV Ozone Cleaner) to eliminate the citrate surfactant. However, exposure of AgNPs to O3 resulted in metal oxidation, rendering the substrate SERS inactive. To remove AgO from the surface, we tested various pH and time combinations and found that the most effective method involved immersing the glass slide with the silver substrate in a pH 4-5 H2O2 solution for 70 seconds. After removing the AgO, SERS analysis revealed the disappearance of citrate from the AgNPs surface present before the cleaning process. Subsequently, immersion in a fumaric acid solution (5x10−5M) was employed to assess SERS enhancement. The SERS signal suggested spontaneous adsorption to the metallic surface, affirming the creation of a SERS-active substrate.
In conclusion, a rapid method for producing a surfactant-free SERS substrate was developed and tested, based on surface O3 cleaning followed by H2O2 reduction.
Keywords: Silver nanoparticles; Surface-Enhanced Raman Spectroscopy (SERS); Spontaneous adsorbtion; Ozone-induced oxidation; H2O2 reduction