Real Time Monitoring Nanoparticles Distance and Structure upon Different Variables

FRANCISCO J. IBAÑEZ; MARIA CELESTE DALFOVO; VESNA STANIC; FELIX G. REQUEJO; LISANDRO GIOVANETTI; CRISTIÁN HUCK IRIART

Campinas

Congreso; 25th Annual User Meeting LNLS/CNPEM (RAU); 2015

Laboratorio Nacional Luz Sincrotron

The nanoparticles (NPs) separation, order, and structure play a crucial role not only in fundamental science but also, in the applied field such as in chemiresistors, localized surface plasmon resonance (LSPR), and surface-enhanced Raman scattering (SERS) for just mention a few. For instance, as long as a metal nanoparticle (Ag or Au) approaches an other metallic center, electromagnetic waves are enhanced leading to an improved SERS or LSPR effect. We recently showed, via GISAXS experiments, that organic -coated NPs change their interparticle distance and film structure upon the exposure to volatile organic compounds (VOCs) and dithiols (nonanedithiol) place-exchange.[1] These results can be correlated with changes in current in chemiresistors. In this presentation I will show the importance of the film (NPs film) deposition method and type of organic coating needed for obtaining correlation. I will also discuss how inter-nanoparticles distance and film correlation changes upon different organic coatings (surrounding NPs), substrate type (graphene vs. silicon) increasing temperature, and addition ofdithiols.[2][1] Dalfovo, et al, and Francisco J. Ibañez*. Real-time Monitoring Distance Changes in Surfactant-coated Au Nanoparticle Films upon Volatile Organic Compounds (VOCs). J. Phys. Chem. C 2015, 119, 5098−5106 [2] Proposal 17155-2014: Dithiols as molecular rulers: the importance of metal nanoparticles separation and graphene towards surface enhanced Raman scattering (SERS)