Rational design of a hierarchical g-C3N4/copper-MOF/Fe3O4 ternary composite for potential photocatalytic applications

Abstract

Photocatalysis is an eco-friendly approach for water remediation. The sun is the primary source of visible-light-driven photocatalysts, making this technique feasible for real-world 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-N₃N₄. The band gap energy of CNMF was calculated as 2.94 eV. Thus, it benefits from 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.