Harnessing magnesium ferrite for sustainable Malachite Green dye degradation: insights into photocatalytic mechanisms, material design, and wastewater remediation

Magnesium ferrite (MgFe₂O₄) is increasingly recognised as a sustainable, visible-light-active, and magnetically recoverable photocatalyst for dye degradation. This review provides a comprehensive and critical analysis of the structural, optical, and magnetic characteristics of MgFe2O4. It further examines how synthesis routes, dopant incorporation, and nanostructural morphology influence its photocatalytic efficiency toward Malachite Green degradation. Special emphasis is placed on understanding the mechanistic aspects of photoexcitation, charge-carrier separation, defect engineering, and the generation of reactive oxygen species (ROS) that underpin its catalytic performance. The article further evaluates recyclability, long-term stability, and process scalability, integrating techno-economic and sustainability perspectives which are very crucial for the industrial implementation. Finally, the review identifies existing knowledge gaps and outlines emerging research opportunities aimed at developing an efficient, durable, and truly green MgFe₂O₄-based photocatalytic systems for the sustainable wastewater treatment applications.