Rational design of a hierarchical g-C3N4/copper-MOF/Fe3O4 ternary composite for potential photocatalytic applications en en Photocatalysis is an eco-friendly approach for water remediation. Solar radiation can serve as a natural source of visible light for photocatalytic processes, making visible-light-driven photocatalysis a promising approach for practical environmental applications. Along with visible light absorption and a highly active surface, the primary requirements of photocatalysts, facile separation for reuse is a key feature for photocatalyst development. Herein, a hierarchically separable ternary composite of g-C3N4/Cu-BTC MOF/Fe3O4, denoted CNMF, was fabricated as a potential photocatalyst material. The g-C3N4 and Fe3O4 were obtained via thermal polymerization and co-precipitation, respectively. Finally, the copper metal-organic framework (Cu-MOF) was synthesized in situ using a solvothermal method in the presence of g-C3N4 and Fe3O4. The morphological, structural, optical, elemental, and magnetic properties of the synthesized materials were investigated. Morphological studies showed a hierarchical architecture in which faceted Cu-MOF crystallites and Fe3O4 nanoparticles were integrated with layered g-C3N4. The band gap energy of CNMF was calculated as 2.94 eV. Thus, it benefits from the high visible absorption of g-C3N4, high redox capacity of Cu-MOF, and easy recyclability and reusability of Fe3O4. CNMF exhibited superparamagnetic behavior with a saturation magnetization of approximately 2.19 emu g-1. The findings of the study confirm the potential of CNMF as a magnetically recoverable candidate for photocatalytic applications. 240 249 Seyed Ali Zargar Department of Materials Science and Engineering Sharif University of Technology, Tehran Iran Ali Moeini Department of Materials Science and Engineering Sharif University of Technology, Tehran Iran Adrine Malek Khachatourian Department of Materials Science and Engineering Sharif University of Technology, Tehran Iran khachatourian@sharif.edu Mohammadamin Aghdamshahriar Department of Materials Science and Engineering Sharif University of Technology, Tehran Iran Seyedamirabbas Estahbanati Department of Materials Science and Engineering Sharif University of Technology, Tehran Iran Photocatalysis Metal-organic framework Hierarchical heterostructure Recoverable photocatalyst Bandgap tuning Electronic modification Vol 6 No 3 Paper 7.pdf [1] N. Morin-Crini, E. Lichtfouse, G. Liu, V. Balaram, A. 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