A fundamental approach about gold nanoparticles

Author(s)

Daniel Grasseschi

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ)
• Defense date: 2015-02-27

Examining board members

Henrique Eisi Toma; Rômulo Augusto Ando; André Luiz Barboza Formiga; Diego Pereira dos Santos; Marcia Laudelina Arruda Temperini

• Advisor: Henrique Eisi Toma

Abstract

The systematic study of gold nanoparticles using fundamental concepts of coordination and physical chemistry is the focus of this thesis, devoting an especial attention for molecular interactions nature at the particles surface. For this goal, the effects of many experimental parameters on the gold nanoparticles formation by the Turkevich method have been studied. It has been shown that not only the morphology and optical properties are controlled by the nucleation and growth processes, but also the chemical properties of the molecular layer at the particles surface. In this way, it has been proved, theoretical and experimentally, that an instable oxidation product of the sodium citrate reaction with the gold salt, a ketonedicarboxilate species, is stabilized by coordination with the superficial gold atoms. This fact leads to distinct chemistry and spectroscopic properties, mainly, related to the reactions at the gold surface. IN addition, a carefully theoretical and experimentally study has been carried out exploring the characteristics of the ethanebis(thioamide) molecules on the surface of different particles. It has been demonstrated that the ketonedicarboxilate presence, from the synthesis process, drastic influences the system properties. (AU)

• FAPESP's process: 11/00037-6 - Study and application of physical and chemical properties of plasmons nanoparticles in intelligent devices
• Grantee: Daniel Grasseschi
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)