Synthesis of magnetite nanoparticles via controlled precipitation method under oxidative atmosphere without dispersants for degradation of organic pollutants

Abstract

Abstract FexOy iron oxide nanoparticles are nanostructured materials that have been extensively studied nowadays. They can be produced by different methods of synthesis. However, to obtain magnetite nanoparticles it is necessary to use an inert atmosphere during synthesis. This work aimed to produce magnetite NPs by the synthesis of nanostructured iron oxide powders using the controlled precipitation method without the need for an inert atmosphere. The synthesis was carried out using iron chloride, iron sulfate and ammonium hydroxide as reagents. In the synthesis process, temperature, dripping time and stirring speed of the mixture were controlled. The powders were characterized by structural (XRD, FTIR) and morphological (TEM) analysis. The results show particles ranging from 4 to 10 nm, with partially spherical morphology. It was possible to produce magnetite NPs without the use of an inert atmosphere, and, therefore, the synthesis by the controlled precipitation method is efficient. The photocatalytic activity tests showed over 80% degradation of the methylene blue dye within a period of 120 min.