Dark Field Spectroelectrochemistry of Metallic Nanoparticles

Abstract

Metallic nanoparticles with plasmonic characteristics constitute a class of materials with interesting properties, such as the effect of enhancing the Raman signal (Surface Enhanced Raman Scattering), photocatalytic capacities of improving the kinetics of redox reactions and unique optical properties related to the surface plasmon. Since these properties lead to various applications, the use of noble metal nanoparticles (NPs), such as gold, silver, and platinum, has been increasingly employed in many techniques. However, much remains to be understood about the effects of the localized surface plasmon resonance (LSPR) phenomenon, emphasizing the need for studies focused on the individual characterization of these particles. On the original project, the electrochemical SERS of different systems undergoing plasmonic catalysis effect are being investigated. Since NPs play an important role in the LSPR that allows plasmonic catalysis and enhances the Raman scattering, conducting a characterization of these entities is crucial for such applications. The Dark-Field Microscopy (DFM) is one of the main techniques to obtain a real-time analysis of the correlation between the LSPR with shape, size, and metallic nature. Therefore, in this project our goal is to monitor different nanoparticles composed by Au, Ag or Pt by Dark-Field Microscopy at different applied potentials in order to gain insight on how the nanoparticles LSPR properties are dependent of the electrochemical events occurring at the surface. The development of this project will contribute to a better understanding of plasmonic catalytic properties of nanoparticles used in electrochemical reactions.