Synthesis of FeCo alloyed nanoparticles with different weight ratios via microemulsion route and studying the magnetic properties

Due to their potential and practical applications, magnetic nanoparticles have been the subject of many researches in recent years due to their potential and practical applications. Among which, their medical applications (e.g: hyperthermia and targeted drug delivery), defensive and communications usages (e.g: electromagnetic waves absorbents) can be mentioned. In this study, the microemulsion method as a facile and promising synthesis method was employed in order to prepare magnetic FeCo alloy nanoparticles with several Fe/Co weight ratios. For this purpose, a micellar system was applied and the reaction of Fe and Co salts reduction was proceeded in the confined spaces in liquid phase. The electromagnetic waves absorption test was conducted to determine the optimum absorbent sample. The results showed that the sample of prepared in the weight ratio of 70:30 possesses a uniform spherical morphology with an average particle size of less than 10 nm. The evaluation of magnetic property of the synthesized samples showed that Fe70Co30 nanoparticles dedicated the highest magnetic saturation of 115 emu g−1. In addition, the magnitude of electromagnetic absorption (return loss) of this sample was measured to be −8.1 dB at 16 GHz which was at the lowest level compared with other samples highlighting the significant effect of Fe/Co weight ratio on final magnetic properties of the alloy system