TY  - CONF
AU  - Ralević, Uroš
AU  - Isić, Goran
AU  - Laban, Bojana
AU  - Vasić Anićijević, Dragana D.
AU  - Vodnik, Vesna
AU  - Bogdanović, Una M.
AU  - Vasić, Vesna M.
AU  - Lazović, Vladimir
AU  - Gajić, Radoš
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/13345
AB  - Metallic nanoparticles are known for their remarkable ability to confine and enhance the electromagnetic fields incident upon them. These nanoobjects have thus been successfully utilized as a platform for enhancing the intensity of light scattered from analyte molecules residing in their close vicinity. A perfect example is surface enhanced Raman spectroscopy (SERS) in which the confined, strong electromagnetic fields transfer the electromagnetic energy to the analyte thereby increasing the magnitude of the analyte phonon-modulated dipole moment and consequently its Raman scattering efficiency [1]. The SERS enhancement factors depend on various factors such as the topology of the metallic nanoobjects, and can be as high as 1011 [1]. Large enhancement factors render SERS a very versatile technique which can be used for detection of extremely small amounts of analyte adsorbed on the surface of metallic nanoobjects [2] as well as for studies on a single molecule level [3].   Here we investigate silver nanoparticle clusters deposited on an insulating substrate as a platform for SERS, using confocal Raman microspectroscopy and a finite element based numerical analysis. The analysis of SERS enhancement based on rigorous numerical simulations of Maxwell equations for the case of plane wave scattering on random silver nanoparticle clusters, shows that the highest field enhancement factors are reached at collective nanoparticle plasmon resonances and become redshifted in elongated clusters with an increasing number of particles. From an inspection of electromagnetic field distribution on nanoparticle surfaces, a conclusion is reached that at least 90% of the total enhancement originates from nanogaps between adjacent nanoparticles, implying that the SERS experiments are sensitive only to adsorbates located in these gaps. The latter conclusion is used to aid the experimental SERS study of the thiacyanine (TC) dye adsorption on the surface of silver nanoparticle clusters. By analyzing the SERS spectra of TC dye coated nanoparticle clusters, we find that the adsorption of this particular dye is strongly influenced by the capping anions which are initially conformed on the surface of the nanoparticles.
PB  - Belgrade : Institute of Physics Belgrade
C3  - PHOTONICA2017 : 6th International School and Conference on Photonics and COST actions: MP1406 and MP1402 : Program and the book of abstracts
T1  - Surface enhanced Raman spectroscopy of thiacyanine coated silver nanoparticle clusters
SP  - 46
EP  - 46
UR  - https://hdl.handle.net/21.15107/rcub_vinar_13345
ER  - 

@conference{
author = "Ralević, Uroš and Isić, Goran and Laban, Bojana and Vasić Anićijević, Dragana D. and Vodnik, Vesna and Bogdanović, Una M. and Vasić, Vesna M. and Lazović, Vladimir and Gajić, Radoš",
year = "2017",
abstract = "Metallic nanoparticles are known for their remarkable ability to confine and enhance the electromagnetic fields incident upon them. These nanoobjects have thus been successfully utilized as a platform for enhancing the intensity of light scattered from analyte molecules residing in their close vicinity. A perfect example is surface enhanced Raman spectroscopy (SERS) in which the confined, strong electromagnetic fields transfer the electromagnetic energy to the analyte thereby increasing the magnitude of the analyte phonon-modulated dipole moment and consequently its Raman scattering efficiency [1]. The SERS enhancement factors depend on various factors such as the topology of the metallic nanoobjects, and can be as high as 1011 [1]. Large enhancement factors render SERS a very versatile technique which can be used for detection of extremely small amounts of analyte adsorbed on the surface of metallic nanoobjects [2] as well as for studies on a single molecule level [3].   Here we investigate silver nanoparticle clusters deposited on an insulating substrate as a platform for SERS, using confocal Raman microspectroscopy and a finite element based numerical analysis. The analysis of SERS enhancement based on rigorous numerical simulations of Maxwell equations for the case of plane wave scattering on random silver nanoparticle clusters, shows that the highest field enhancement factors are reached at collective nanoparticle plasmon resonances and become redshifted in elongated clusters with an increasing number of particles. From an inspection of electromagnetic field distribution on nanoparticle surfaces, a conclusion is reached that at least 90% of the total enhancement originates from nanogaps between adjacent nanoparticles, implying that the SERS experiments are sensitive only to adsorbates located in these gaps. The latter conclusion is used to aid the experimental SERS study of the thiacyanine (TC) dye adsorption on the surface of silver nanoparticle clusters. By analyzing the SERS spectra of TC dye coated nanoparticle clusters, we find that the adsorption of this particular dye is strongly influenced by the capping anions which are initially conformed on the surface of the nanoparticles.",
publisher = "Belgrade : Institute of Physics Belgrade",
journal = "PHOTONICA2017 : 6th International School and Conference on Photonics and COST actions: MP1406 and MP1402 : Program and the book of abstracts",
title = "Surface enhanced Raman spectroscopy of thiacyanine coated silver nanoparticle clusters",
pages = "46-46",
url = "https://hdl.handle.net/21.15107/rcub_vinar_13345"
}

Ralević, U., Isić, G., Laban, B., Vasić Anićijević, D. D., Vodnik, V., Bogdanović, U. M., Vasić, V. M., Lazović, V.,& Gajić, R.. (2017). Surface enhanced Raman spectroscopy of thiacyanine coated silver nanoparticle clusters. in PHOTONICA2017 : 6th International School and Conference on Photonics and COST actions: MP1406 and MP1402 : Program and the book of abstracts
Belgrade : Institute of Physics Belgrade., 46-46.
https://hdl.handle.net/21.15107/rcub_vinar_13345

Ralević U, Isić G, Laban B, Vasić Anićijević DD, Vodnik V, Bogdanović UM, Vasić VM, Lazović V, Gajić R. Surface enhanced Raman spectroscopy of thiacyanine coated silver nanoparticle clusters. in PHOTONICA2017 : 6th International School and Conference on Photonics and COST actions: MP1406 and MP1402 : Program and the book of abstracts. 2017;:46-46.
https://hdl.handle.net/21.15107/rcub_vinar_13345 .

Ralević, Uroš, Isić, Goran, Laban, Bojana, Vasić Anićijević, Dragana D., Vodnik, Vesna, Bogdanović, Una M., Vasić, Vesna M., Lazović, Vladimir, Gajić, Radoš, "Surface enhanced Raman spectroscopy of thiacyanine coated silver nanoparticle clusters" in PHOTONICA2017 : 6th International School and Conference on Photonics and COST actions: MP1406 and MP1402 : Program and the book of abstracts (2017):46-46,
https://hdl.handle.net/21.15107/rcub_vinar_13345 .