Synthesis of magnetite nanoparticles by controlled precipitation under oxidative atmosphere

Abstract

Fe3O4 nanoparticles have been extensively studied due to their electromagnetic characteristics. Magnetite NPs can be produced by different methods. However, most of the methods use an inert atmosphere for synthesis. Therefore, this work aimed to produce magnetite NPs using the controlled precipitation method under an oxidant atmosphere. The synthesis was carried out using iron chloride, iron sulfate and ammonium hydroxide as reagents. Temperature, dripping time and stirring speed were the controllable variables. The NP powders were characterized by structural (XRD, FTIR), magnetic (vibrating sample magnetometry, VSM), and morphological (TEM) analyses. The results show particles ranging from 4 to 10 nm, with specific surface area of 52 m2/g and irregular morphology. The saturation magnetization (Ms) was 51.5 emu/g. The photocatalytic activity tests showed over 80 % discoloration of the methylene blue dye within 120 min. Therefore, the synthesis of magnetite NPs by the precipitation method under oxidative atmosphere was efficient.