This study presents a comprehensive investigation into the synthesis and application of a novel composite photocatalyst, Mg0.75Ce0.25Fe12O19@ZIF-67, for the degradation of Rhodamine B (RhB) dye under sunlight. The synthesis involved preparing Mg0.75Ce0.25Fe12O19 and ZIF-67 frameworks, followed by the fabrication of the composite catalyst. Various characterization techniques, including XRD, SEM, EDX, and FTIR, were used to assess the structural, morphological, and compositional properties of the synthesized materials. Photocatalytic experiments showed that the composite catalyst achieved a degradation efficiency of 90% for RhB, significantly higher than individual components. The effects of catalyst type, dosage, and pH on the degradation process were systematically investigated. A proposed mechanism elucidated the role of the Mg0.75Ce0.25Fe12O19@ZIF-67 cocatalyst in RhB degradation under solar light, highlighting the generation of radicals as key contributors to the degradation process. RhB is a common organic dye pollutant with significant environmental and health concerns due to its carcinogenic effects and toxicity. Advanced oxidation processes (AOPs) are effective in removing micropollutants by generating reactive radicals such as sulfate (SO4•-), hydroxyl (•OH), and superoxide (O2•-). Metal-organic frameworks (MOFs), including ZIF-67, are crystalline materials with large surface areas and adjustable pores, making them valuable for applications such as gas storage and catalysis. The Mg0.75Ce0.25Fe12O19@ZIF-67 composite catalyst demonstrates high efficiency in RhB degradation under sunlight, offering a promising solution for the removal of organic dyes from water.This study presents a comprehensive investigation into the synthesis and application of a novel composite photocatalyst, Mg0.75Ce0.25Fe12O19@ZIF-67, for the degradation of Rhodamine B (RhB) dye under sunlight. The synthesis involved preparing Mg0.75Ce0.25Fe12O19 and ZIF-67 frameworks, followed by the fabrication of the composite catalyst. Various characterization techniques, including XRD, SEM, EDX, and FTIR, were used to assess the structural, morphological, and compositional properties of the synthesized materials. Photocatalytic experiments showed that the composite catalyst achieved a degradation efficiency of 90% for RhB, significantly higher than individual components. The effects of catalyst type, dosage, and pH on the degradation process were systematically investigated. A proposed mechanism elucidated the role of the Mg0.75Ce0.25Fe12O19@ZIF-67 cocatalyst in RhB degradation under solar light, highlighting the generation of radicals as key contributors to the degradation process. RhB is a common organic dye pollutant with significant environmental and health concerns due to its carcinogenic effects and toxicity. Advanced oxidation processes (AOPs) are effective in removing micropollutants by generating reactive radicals such as sulfate (SO4•-), hydroxyl (•OH), and superoxide (O2•-). Metal-organic frameworks (MOFs), including ZIF-67, are crystalline materials with large surface areas and adjustable pores, making them valuable for applications such as gas storage and catalysis. The Mg0.75Ce0.25Fe12O19@ZIF-67 composite catalyst demonstrates high efficiency in RhB degradation under sunlight, offering a promising solution for the removal of organic dyes from water.