Synthesis of metal nanoparticles supported in organofunctionalized mesoporous silica

Author(s)

Natália Fattori

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Química
• Defense date: 2014-11-11

Examining board members

Yoshitaka Gushikem; Jacqueline Arguello; Wania da Conceição Moreira; Juliano Alves Bonacin; André Luiz Barboza Formiga

• Advisor: Yoshitaka Gushikem

Abstract

The present work describes a new method for preparing metal nanoparticles supported on organofuncionalized mesoporous silica. Two different substrates were used: a mesoporous silica constituted by a highly ordered and uniform porous framework, with parallel cylindrical pore channels packed in a hexagonal array (SBA-15), and a mesoporous silica characterized by a disordered porous framework, with non-uniform size and shape, distributed and interconnected randomly throughout the porous structure (SMD). Both substrates were chemically modified with two different functional groups constituted of organic cations (R+Cl-) with ion-exchange properties, derivative from the molecules 1-methylimidazole (Imi) and 4,4?-bipyridine (Bipy). In both cases, the ion-exchange properties of the cationic groups attached to the silica surface allows the retention of anionic noble metal complex ([AuCl4]-, [PtCl6]2- e [PdCl4]2-), confined within the porous structure. These species were converted in situ into metal nanoparticles by means of reduction of the metal ions with proper reducing agents. The substrates modified with the functional group Imi were used as supports for the preparation and stabilization of noble metal nanoparticles (Au, Pt, Pd and metal alloys Au-Pt, Au-Pd and Pd-Pt). The substrates modified with the functional group Bipy were used as supported for the preparation of gold nanoparticles (AU)

• FAPESP's process: 11/13434-3 - Design of Catalysts Based on Metal Nanoparticles Supported on Organofunctionalized Mesoporous Silicas
• Grantee: Natalia Fattori
• Support Opportunities: Scholarships in Brazil - Doctorate