Hyperthermia studies of ferrite synthesized in the presence of nanoparticles cotton

MFe2O4 (M = Co, Fe, Mn) compounds were synthesized using hydrothermal treatment in the presence of medicinal cotton. Two sets of nanoparticles were produced for each composition and subsequently characterized by XRD, TEM and SEM. The nanoparticles obtained from the solution display the expected spin& structure and different mean sizes (below 16 nm); the nanoparticles embedded in cotton were subjected to a calcination process for cotton elimination. Regarding these calcinated samples, the spin& structure was maintained for CoFe2O4, a mixture of phases was identified for the M = Mn sample and, in the case of iron, the magnetite phase was converted to hematite (alpha-Fe2O3). After cotton elimination the samples exhibit a morphology which evidences the role of cotton as a template. To evaluate the quality of the nanoparticles for hyperthermia, SQUID magnetometry and MOssbauer spectroscopy were used to perform the magnetic characterization of all products, and the specific loss power (SLP) was determined by induction heating measurements. All the ferrite NP obtained by hydrothermal synthesis in the presence of cotton display good hyperthermia performance. MnFe2O4 nanoparticles exhibit the highest SLP value, 90 W g(-1), followed by Fe3-xO4, and CoFe2O4. In the case of CoFe2O4, the specific loss power of the NP obtained after cotton elimination is enhanced by 50% which is explained by the NP morphology adopted from the cotton template during the synthesis.