Comparative study on photocatalytic degradation of methylene blue using CoFe2O4, NiFe2O4 and CoNiFe2O4 prepared by sol-gel method

Abstract

This work focuses on synthesizing ferrites specifically cobalt (CoFe₂O₄), nickel ferrite (NiFe₂O₄), and mixed ferrites cobalt nickel ferrite (CoNiFe₂O₄), via the sol gel method for use in photocatalytic degradation of methylene blue (MB) in water treatment applications. Using a glass substrate and pulsed laser deposition, nanostructured thin films are created. Utilizing X-ray diffraction, the structural properties of these ferrites are investigated. The findings showed that the ferrites formed in a crystalline cubic shape. According to atomic force microscope utilization chart ,the granularity cumulating distribution, the average diameter for NiFe₂O₄, CoFe₂O₄, and CoNiFe₂O₄ are 83.8, 86.7, and 83.4 nm, respectively, according to atomic force microscopy. It has been demonstrated in field emission microscopic images that ferrite nanoparticles agglomerate because of their magnetic properties and the binding of parent particles held by surface interaction, like the Van Der Waals force, between them. The energy gap for nano-ferrites is examined to explain the photocatalytic activity of methylene blue dye. The CoFe₂O₄ has the smallest energy gap (Eg=1.97 eV). This is due of improved charge separation, less recombination, and improved surface characteristics brought about by nickel incorporation, NiFe₂O₄ shows superior catalyst efficiency even though CoFe₂O₄ has a lower band gap. This increases the photocatalytic degradation efficiency of CoNiFe₂O₄.