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 x Zn 1‐x Fe 2 O 4 ] ( 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 0.8 Zn 0.2 Fe 2 O 4 (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.