Preparation, characterization and photocatalytic activity for degradation of methylene blue by ZnFe₂O₄/Bentonite nanocomposite

In this work, we report synthesis of bentonite (BT) supported softmagnetic ZnFe2O4 nanoparticles to obtain ZnFe2O4/BT. The composition, surface morphology and optical properties of the sample  were characterized by XRD, EDX, FTIR, SEM and DRS analysis. The results of SEM show that the ZnFe2O4 nanoparticles spread on the thin layer of bentonite due to intercalation with bentonite. The band gaps of Bentonite, ZnFe2O4 and ZnFe2O4/BT are 2.18; 1.95 and 1.82 eV respectively. The photocatalytic activity of the samples is evaluated by the degradation of methylene blue (MB)  in the presence of H2O2 under visible light radiation. The results indicated that the ZnFe2O4/BT samples exhibited higher removal efficiencies than the pure ZnFe2O4 ferrites. The enhanced photocatalytic activity of the ZnFe2O4/BT is explained due to visible light adsorption ability, and larger interfacial area, as well as the efficient separation mechanism of photoinduced electron and holes.