Name: GIORGIO GOULART
Type: MSc dissertation
Publication date: 16/03/2017
Advisor:
Name |
Role |
|---|---|
| EDUARDO PERINI MUNIZ | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| EDSON PASSAMANI CAETANO | External Examiner * |
| EDUARDO PERINI MUNIZ | Advisor * |
| JOSÉ RAFAEL CÁPUA PROVETI | Internal Examiner * |
| RODRIGO DIAS PEREIRA | External Examiner * |
Summary: Cobalt ferrites were prepared from the sol gel proteic method, using metallic nitrates and pectin from orange albedo as a precursor. The samples were isothermally treated at 973, 1073 and 1173 K for 4, 8, 12, 16, 24, 36 and 48 hours. X-Ray Scattering, Mossbauer and Fourrier Transform Infrared Spectroscopy were performed in the characterization of the powders. The results show the presence of CoFe2O4, Fe2O3 and Co3O4 and their concentrations bound to the heat treatment temperature. Grain sizes from 71 to 130 nm were found as well as defects in the crystalline lattice, configured by the additional peak found in the infrared and lattice parameters above ideal values. The concentration of Co3O4 and the defects decrease with the treatment time, indicating a diffusive phenomenon.
