Significantly enhanced photocatalytic performance of CoNi-MOF/MoS₂ for efficient environmental remediation: Antibiotic degradation, hydrogen evolution, and antibacterial activity

Abstract

A binary metal composition of Co and Ni-based metal-organic frameworks (MOFs) was deposited on an MoS₂ flower-like structure and was synthesized and evaluated as a photocatalyst for the degradation of methylene violet (MV) dye and the antibiotic tetracycline (TC) in aqueous solutions under UV and visible light irradiation. Morphological and optical analyses confirmed the deposition of CoNi-MOF on the MoS₂ surface. The resulting binary CoNi-MOF/MoS₂ nanocomposite exhibited remarkable photocatalytic activity, achieving degradation efficiencies of 98 % for MV and 92 % for TC, significantly outperforming individual Co-MOF and CoNi-MOF catalysts. Under visible light irradiation, the degradation time was notably reduced compared to UV light irradiation, highlighting the material's superior activity in the visible light range. Subsequently, MoS₂ played a pivotal role as a template that accelerated the separation of electron-hole pairs, while the binary metal organic framework acted as an electron sink, enhancing interfacial charge transfer and promoting the degradation of antibiotics and dyes. CoNi-MOF/MoS₂ exhibited outstanding electrochemical activity for the hydrogen evolution reaction (HER) in an acidic medium, demonstrating a low overpotential of 86.7 mV, a Tafel slope of 47.5 mV/dec, and excellent long-term stability of 12 h. Furthermore, the binary CoNi-MOF with MoS₂ composite demonstrated significant antibacterial activity against S. mutans, facilitated by the generation of reactive oxygen species (ROS), effectively inhibiting bacterial growth.