Surface Plasmon Resonances in Silver Nanostars

Author(s)

Reyes Gomez, Faustino ^{[1, 2]} ; Rubira, Rafael J. G. ^[3] ; Camacho, Sabrina A. ^[3] ; Martin, Cibely S. ^[3] ; da Silva, Robson R. ^[4] ; Constantino, Carlos J. L. ^[3] ; Alessio, Priscila ^[3] ; Oliveira, Jr., Osvaldo N. ^[4] ; Ricardo Mejia-Salazar, J. ^{[4, 5]}

Affiliation

^[1] Univ Valle, Dept Fis, Cali 25360 - Colombia

^[2] Univ Cantabria, Dept Appl Phys, Avda Los Castros S-N, E-39005 Santander - Spain

^[3] Sao Paulo State Univ UNESP, Sch Technol & Appl Sci, Campus Presidente Prudente, BR-19060900 Sao Paulo - Brazil

^[4] Univ Sao Paulo, Sao Carlos Inst Phys, POB 369, BR-13560970 Sao Carlos, SP - Brazil

^[5] Natl Inst Telecommun Inatel, BR-37540000 Santa Rita Do Sapucai, MG - Brazil

• Document type: Journal article
• Source: SENSORS; v. 18, n. 11 NOV 2018.
• Web of Science Citations: 3

Abstract

The recent development of silver nanostars (Ag-NSs) is promising for improved surface-enhanced sensing and spectroscopy, which may be further exploited if the mechanisms behind the excitation of localized surface plasmon resonances (LSPRs) are identified. Here, we show that LSPRs in Ag-NSs can be obtained with finite-difference time-domain (FDTD) calculations by considering the nanostars as combination of crossed nanorods (Ag-NRs). In particular, we demonstrate that an apparent tail at large wavelengths (lambda greater than or similar to 700 nm) observed in the extinction spectra of Ag-NSs is due to a strong dipolar plasmon resonance, with no need to invoke heterogeneity (different number of arms) effects as is normally done in the literature. Our description also indicates a way to tune the strongest LSPR at desired wavelengths, which is useful for sensing applications. (AU)

• FAPESP's process: 16/06612-6 - Printed and implantable biosensor made from biopolymers for long-term monitoring
• Grantee: Robson Rosa da Silva
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/14262-7 - Nanostructured films from biologically-relevant materials
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 16/09634-0 - Interaction between biomembrane models based on Langmuir films and giant unilamellar vesicles (GUVs) with triazine herbicides and detection via SERS spectroscopy.
• Grantee: Rafael Jesus Gonçalves Rubira
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 16/12311-9 - Transversal magneto-optical Kerr effect for the design and development of biosensors
• Grantee: Jorge Ricardo Mejía Salazar
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/01897-4 - Synthesis of gold nanoparticles for enhancement of Raman scattering (SERS) and fluorescence (SEF) targeting sensory applications
• Grantee: Sabrina Aléssio Camacho
• Support Opportunities: Scholarships in Brazil - Doctorate