Shielding material from microwave radiation with additives of magnetite nanoparticles - Fe3O4, obtained by the method of solution combustion
Iron oxide (Fe3O4) is an oxide, which has found many practical applications. Obtaining of iron oxides and their application are the actual direction of investigation. The aim of the work is obtaining of iron oxide nanoparticles and studying their physico-chemical characteristics. The iron oxide magnetic nanoparticles were prepared by using a solution combustion synthesis. The eﬀect of ratio of iron nitrate to citric acid (1:1; 1:1.5: 1:2) on the structure has been studied. Obtained iron oxide nanoparticles was characterized by XRD, SEM and optical microscope. The average size of iron oxide crystallites was found by Scherrer’s formula and it was 20 nm for the ratio 1:1, 18 nm for 1:1.5, 13 nm for 1:2, respectively. Investigation by scanning electron microscopy showed that the change in the ratio of iron nitrate to citric acid from 1:1 to 1:2 results in considerable change in morphology, dispersity of the product increases with the increase in the content of citric acid and the size of agglomerates decrease. It has been established that the addition of magnetite nanoparticles synthesized by the method of solution combustion aﬀects the shielding properties of cement stone. The best result of attenuation of 18.3 dB showed a sample with a content of 0.5% magnetite nanoparticles at a frequency of 12.5 GHz. At a concentration of 1% magnetite nanoparticles, the attenuation of microwave radiation can be achieved at a frequency of 13 GHz of 16.3 dB.