Síntese de nanopartículas magnéticas ferritas mistas de metais de transição derivadas de polímero natural (Quitosana) – método sol-gel

Abstract

This study presents the synthesis by Sol-Gel method using chitosan as a polymeric precursor as a simple and inexpensive alternative in the synthesis of Cobalt (CoFe2O4) and Nickel (NiFe2O4) ferrites, focusing on the analysis of the temperature influence at which synthesis. Ferrites are nanometric materials with very particular magnetic properties such as super paramagnetism, as well as other magnetic and physical properties that make them have great value to the industry, especially those of high technology and even uses in medical equipment. However, the growing demand and new applications appearing every day, developing a synthesis method that is cheap, simple, fast and efficient is very important. X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TG-DTG) techniques were applied to samples synthesized at 350, 500, 700 and 900 ºC in order to compare them. It was observed that the treatment at 900 ºC showed the best results, with good crystallite sizes, reasonable percentage of crystalline phase, less interference from organic compounds that prevent the formation of crystals and good thermal stability.