NH2-MIL-125(Ti) nanoparticles decorated over ZnO microrods: An efficient bifunctional material for degradation of levofloxacin and detection of Cu(II)

Abstract

The evolution of MOF/metal oxide composites has recently been recognized as excellent photocatalysts and sensors establishing the door for research into the treatment and detection of toxic contaminants from an aqueous phase. The decoration of MOF nanoparticles onto the surface of ZnO microrods with substantial benefits was significantly studied in the current study. Herein, we have developed NH2-MIL-125(Ti)/ZnO heterostructure as a dual functional platform for the degradation of levofloxacin (LVX) as well as detection of Cu(II) ions. The heterostructure was fabricated by a simple ultrasonic-assisted hydrothermal method followed by numerous characterizations. NH2-MIL-125(Ti)/ZnO-(II) showed an average crystallite size of 47.64 nm, surface area of 39.508 m2/g, and band gap of 2.98 eV. The morphological studies revealed the deposition of NH2-MIL-125(Ti) nanoparticles on ZnO microrods in high density. Under solar irradiation, 90% degradation of LVX was attained in 240 min at optimum conditions (pH–7, catalyst dose–0.25 g/L, and LVX concentration–10 mg/L). The improved photocatalytic ability of composite in contrast to MOF and ZnO could be usually ascribed to the interface created between them, assisting the charge transfer. Additionally, the current system exhibited good recyclability over five runs. Further, to realize the application of NH2-MIL-125(Ti)/ZnO-(II) as a sensor, the material was exposed to the solution of Cu(II) ions and significant quenching was observed demonstrating high selectivity of the current system. Moreover, the detection limit in the linear range of 0–25 μM was calculated to be 1.135 μM which indicated a good sensitivity of the prepared material towards Cu(II) ions, sufficiently low to detect micromolar concentrations of Cu(II). All in all, this study provided a simple and propitious approach for fabricating solar light active photocatalysts for the degradation of organic pollutants and their dual role as fluorescent (FL) sensor towards the determination of Cu(II) ions from aqueous phase.