New Al/Mn blend driven sunlight-photocatalytic of ZnFe₂O₄ nano-catalyst for effective treatment of cationic and anionic dyes

In this study, pure and Al/Mn codoped ZnFe₂O₄ nanocatalysts have been prepared by using a coprecipitation method for efficient sunlight photodegradation of synthetic rose Bengal, malachite green, and reactive black 5 dyes. The photocatalytic results verified that the incorporation of Al/Mn ions into the ZnFe₂O₄ structure strongly improves the photo-activity with a lowering of the reaction time. Phase identification by X-ray diffraction analysis proved the formation of a face-centered cubic ZnFe₂O₄ spinel structure. The surface homogeneity of ZnFe₂O₄ powder was improved by the addition of Al/Mn ions with the formation of nanosized particles around 21 nm. The band gap energy of ZnFe₂O₄ ferrite was estimated to be 1.88 eV, which decreased to 1.7 eV by incorporation of Al/Mn ions. Under solar spectral irradiation, the Al/Mn modified ZnFe₂O₄ photocatalyst efficiently removed rose Bengal, malachite green, and reactive black 5 dyes with measured photocatalytic efficiency of 98%, 91%, and 94%, respectively. The measured photocatalytic parameters verified that Al/Mn codoped ZnFe₂O₄ nanopowder is an active sunlight-driven photocatalyst for organic dye remediation. The reuse experiments for dyes degradation and the mineralization analysis confirmed the stability of ZnFe₂O₄ catalyst with the formation of final non-hazardous products.