Syntheses, magnetic and structural properties of core-shell FePc and FePr nanoparticles annealed by oxygen and nitrogen at different temperatures

In recent years there is a growing interest in synthesizing of novel iron-based nanoparticles and nanocomposites with high efficiency of thermal energy transfer suitable for use in magnetic fluid hyperthermia. Oxygen and nitrogen annealed phthalocyanine and porphyrin (graphene) can significantly influence magnetic properties as compared with those of pyrolysis of iron based graphene. We investigate structural and magnetic properties of synthesized by a one-step process of thermal decomposition (Pyrolysis) of iron phthalocyanine (FePc) and iron porphyrin (FePr) nanoparticles of “core-shell” structure with the high magnetic moment of core (such as Fe), and the shell consists of a biocompatible material (e.g. iron oxide, iron nitride or carbide). We conducted investigations of structural and magnetic properties of these materials annealed by oxygen and nitrogen at different temperatures using X-ray diffraction (XRD), measurements of XPS spectra, high resolution SEM/STEM images, magnetometry PPMS measurements. The oxygen and nitrogen content and structures are directly achieved from the XPS analysis. The measured magnetization of magnetic saturation and coercivity as well as the specific absorption rate (SAR) show that these materials attractive for magnetic hyperthermia medical applications. Hysteresis loop of the (Fe-Fe₃C)@C and (Fe-Fe₃O₄)@C nanocomposites are of special interest because of high M_r/M_s ratio.