The Fabrication of Gold Nanostructures as SERS Substrates for the Detection of Contaminants in Water

• Published in: Nanomaterials (Basel, Switzerland) Vol. 14; no. 18; p. 1525
• Main Authors: Visbal, Cristhian A, Cervantes, Wilkendry Ramos, Marín, Lorena, Betancourt, John, Pérez, Angélica, Diosa, Jesús E, Rodríguez, Luis Alfredo, Mosquera-Vargas, Edgar
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 20-09-2024; MDPI
• Subjects: Absorption spectroscopy; Annealing; Comparative analysis; Contaminants; dewetting; Dielectric films; Ecosystems; Electron microscopes; Fabrication; Glass substrates; Gold; gold nanostructures; Heat treatment; Methods; Morphology; Nanoparticles; Nanostructure; Particle size; Raman spectroscopy; Rhodamine; Rhodamine B; Scanning electron microscopy; SERS; Software; Substrates; surface plasmon; Surface plasmon resonance; Thin films; Water pollution; Colombia; United States > US; dewetting; Rhodamine B; SERS; gold nanostructures; surface plasmon
• ISSN: 2079-4991; 2079-4991
• DOI: 10.3390/nano14181525

Gold nanostructures (AuNSs) were used to fabricate surface-enhanced Raman spectroscopy (SERS) substrates. These AuNSs were produced using the solid-state dewetting method from thin films. The fragmentation process was studied at 300 °C, with durations of thermal treatment of 1, 3, 6, and 12 h. These SERS substrates were then employed to detect Rhodamine B (RhB) as the model analyte, simulating a contaminant in the water at a concentration of 5 ppm. The morphology of the AuNSs was examined using SEM, which revealed a spheroidal shape that began to coalesce at 12 h. The size of the AuNSs was estimated to range from 22 ± 7 to 24 ± 6 nm, depending on the annealing time. The localized surface plasmon resonance of the AuNSs was determined using absorption spectroscopy, showing a shift as the annealing time increased. The SERS signals of RhB adsorbed on the AuNS substrates were validated by performing a 10 × 10 point map scan over each sample surface (1, 3, 6, and 12 h), and a comparative analysis showed no significant differences in the positions of the bands; however, variations in intensity enhancement ranged from 5 to 123 times at 6 and 1 h, respectively.