Synthesis of Fe3O4, Fe3O4-SiO2 and Fe3O4-SiO2-NiO naomagnetic had been carried out using coprecipitation and solvothermal methods. Fe3O4, Fe3O4-SiO2 and Fe3O4-SiO2-NiO nanomagnets were applied to degrade methylene blue dye. Fe3O4, Fe3O4-SiO2 and Fe3O4-SiO2-NiO nanomagnets were characterized using XRD, SEM-EDS, VSM and DRS. The XRD pattern shows that the sample is composed of Fe3O4, Fe3O4-SiO2 a…