Comparative Studies of Magneto-Optical and Photocatalytic Properties of Magnetically Recyclable Spinel ZnFe2O4 Nanostructures by Combustion Methods

Spinel ZnFe2O4 nanoparticles (NPs) were successfully synthesized by a simple microwave irradiation method (MIM) using glycine as the fuel. For the comparative study purpose, it was also prepared by conventional heating (CHM) method. Powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), high resolution scanning electron microscope (HR-SEM), high resolution transmission electron microscope (HR-TEM), energy dispersive X-ray (EDX) spectra, selected area electron diffraction (SAED) analysis showed that the samples were pure phase spinel ZnFe2O4 nanoparticles-like morphology without any other secondary phase impurity. UV-Visible diffuse reflectance spectra (DRS) and room temperature photoluminescence (PL) spectra were confirmed the optical bandgap (E-g) and defects state of the samples. The calculated E-g values of the samples are 1.91 eV and 2.08 eV for ZnFe2O4-MIM and ZnFe2O4-CHM, respectively. Vibrating sample magnetometer (VSM) analysis show the Ms value is 37.66 emu/g for ZnFe2O4-MIM, which is higher than ZnFe2O4CHM (24.23 emu/g) sample, which confirm both the products showed superparamagnetic behavior. ZnFe2O4-MIM was found to have higher surface area than ZnFe2O4-CHM, which in turn leads to the improved performance toward the photocatalytic degradation (PCD) of 4-chlorophenol (4-CP) and it was found that the sample ZnFe2O4-MIM show higher PCD efficiency (91.43%) than ZnFe2O4-CHM (84.65%), also the samples show high activity, good reusability, remarkable stability and environmentally friendly materials for industrial and technological applications.