Nanoparticles and mesoporous systems for catalytic, magnetic and solid oxide fuel cells

• Grant number: 08/00140-9
• Support type: Regular Research Grants
• Duration: September 01, 2008 - August 31, 2009
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal researcher: Marcia Carvalho de Abreu Fantini
• Grantee: Marcia Carvalho de Abreu Fantini
• Home Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

This project aims the growth and characterization of nanoparticles formed by oxides of iron, titanium, aluminum, cerium, paladium and lanthanum, prepared by sol-gel, as well as the study of their catalytic and paramagnetic properties. The proposal involves a detailed study about the synthesis of coloidal suspensions made of oxy-hydroxides of transition metals and rare earths. Also, metallic films of palladium gold and silver will be prepared and studied. The local structure evolution of the xerogels in a atomic sacle ranging to 20 nm will be analyzed by X-ray diffraction and small angle scattering, XRD and SAXS, respectively. These results will be compared to transmission electron microscopy (TEM) pictures. The formation mechanisms of the colloidal suspensions, previous to gelatination, drying, sintering will be analyzed systematically, aiming to establish the synthesis conditions, the structure and other properties of the systems. Fotr the rare-earth oxides, the properties related to heterogeneous catalysis in combustion motors will be focalized. This study has the prior goal to establish better conditions to the growth of thin films formed by these compounds. The paramagnetic properties of iron bio-compatible nanoparticles will be investigated for biomedical applications in image diagnosis by RMN. Measurements of Mössbauer spectroscopy and EPR will be used to characterize these systems. The project involves the study of mesoporous ceramics based on silicon and zircon, having a periodic arry of pores for applications in devices of controlled chemical or drug release, ionic conductors, heavy metal adsorbents and support for catalysers. All those systems present as a common aspect, their nanometric sizes, responsible for the specific properties adequate at each application. This project will be executed by 2 reseachers of the Crystallography Laboratory: Dra. Márcia C.A. Fantini (coordinator) and Dr. Giancarlo E.S. Brito (PHD-professor). (AU)