The Effect of Silica on Photocatalytic Degradation of Methylene Blue Using Silica-Coated NiZn Ferrite Nanoparticles

Nickle zinc ferrite (NiZnFe2O4) magnetic nanoparticle (MNPs) has been successfully synthesized using co-precipitation method. NiZnFe2O4 was coated SiO2 (NiZnFe2O4/SiO2) using Stöber method with various concentrations of (5%, 10%, 15%, 20%, 30%, and 50%). MNPs sample has a spinel ferrite phase confirmed by X-ray diffraction (XRD) measurements. The results of the functional group analysis performed using Fourier transform infrared (FTIR) showed an M-O tetrahedral vibrational bond found a wavelength of 347 cm-1. After coated silica, Si-O-Si vibrational bonds appear at wavelengths of 1033.85 cm1. Magnetic properties were measured using vibrating Sample Magnetometer (VSM), the result shows that has maximum saturation magnetization of NiZnFe2O4 22.5 emu.gram-1 and decreased to 16.9 emu.gram-1 after coating. In figure 1 show that the photodegradation activity of MNPs was carried out with a variation of irradiation time. Result of the photodegradation activity of methylene blue shows that NiZnFe2O4/SiO2 are higher than NiZnFe2O4. Sample of NiZnFe2O4/SiO2 has the highest photodegradation rate up to 96%. The existence of SiO2 layer on the surface of bare MNPs increases the surface reactivity of samples.