Surface plasmon resonances in silver nanostars

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 ob...

Descripción completa

Detalles Bibliográficos
Autores: Gómez, Faustino Reyes, Rubira, Rafael J. G. [UNESP], Camacho, Sabrina A. [UNESP], Martin, Cibely S. [UNESP], da Silva, Robson R., Constantino, Carlos J. L. [UNESP], Alessio, Priscila [UNESP], Oliveira, Osvaldo N., Mejía-Salazar, J. Ricardo
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/188339
Acceso en línea:http://dx.doi.org/10.3390/s18113821
http://hdl.handle.net/11449/188339
Access Level:acceso abierto
Palabra clave:Ag nanostars
Metallic nanoparticles
Plasmonic biosensing
Descripción
Sumario: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 (λ > 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.