Synthesis and characterization of nanosheet NiMoO4 powder as a highly efficient and reusable catalyst for environmental remediation

The simple and eco-friendly co-precipitation method is used to synthesize nickel molybdate in an aqueous solution at room temperature. The physical properties of NiMoO 4 are investigated using several techniques, such as X-ray diffraction (XRD), which perfectly fits the crystalline α-form of NiMoO 4 . Moreover, scanning electron microscope (SEM) images show nanosheet-like particles. The atomic force microscopy (AFM) measurements reveal high roughness of the particle’s surface. Furthermore, the investigations into the main electronic levels of α-NiMoO 4 suggest a strong UV–visible light absorption. The optical band gap is found to be about 2.36 eV. Then, the photocatalytic activity of the synthesized NiMoO 4 nanoparticles (NPs) is tested against methylene blue (MB) dye as a pollutant model. The obtained results reveal good capacity of MB degradation even in the dark. It exhibits a degradation efficiency up to 87% within 60 min, under visible-light illumination, and 44% in the dark. The photocatalytic stability of NiMoO 4 NPs is studied as well. So, successive photocatalytic cycles show that the photocatalyst is still efficient even after five cycles. The obtained results permit to optimistically consider α-NiMoO 4 nanosheets as talented photocatalyst for environmental applications, such as photodegradation of hazardous pollutants.