Recyclable Porous Manganese Substituted Zinc Ferrite Nanoparticles for Efficient Photocatalytic Degradation of Organic Dyes

Abstract

The degradation of dyes in wastewater via photocatalysis offers a sustainable and effective treatment method, requiring materials with high porosity and suitable band gaps. This study explores manganese (Mn) substitution in zinc ferrite [Mn_xZn_1-xFe₂O₄] (x = 0–1) to tune porosity and band gap. X-ray diffraction confirmed the crystal structure and Mn incorporation, while TEM showed an average particle size of 54.32 nm. UV–vis diffuse reflectance spectroscopy revealed a red shift in the absorption edge with increasing Mn content, enhancing visible-light responsiveness. Mn substitution increased porosity and reduced the band gap due to lattice strain and new electronic states, improving optical properties. The Mn_0.8Zn_0.2Fe₂O₄ (MZ4) catalyst demonstrated outstanding performance, achieving 90%, 90%, and 88% degradation of RhB, MB, and ChT dyes, respectively, under visible-light irradiation within 240 min. These findings highlight the potential of Mn-substituted zinc ferrite nanoparticles for efficient photocatalytic dye degradation.