Abstract
<title>Abstract</title> <p> Zn <sub>2</sub> V <sub>2</sub> O <sub>7</sub> (ZV) nanoparticles (NPs) were synthesized through simple co-precipitation method. The synthesized nanoparticles were comprehensively characterized using XRD, FTIR, UV–DRS, SEM, TEM, PL, and XPS techniques to evaluate their structural, optical, and morphological properties. XRD analysis confirmed the formation of a well-crystallized orthorhombic ZnV <sub>2</sub> O <sub>7</sub> phase with nanoscale crystallite dimensions, while FTIR spectra verified the presence of characteristic Zn–O and V–O vibrational bands. UV–DRS studies revealed strong absorption in the visible region with a band gap energy of 2.91 eV. SEM–EDX and TEM analyses demonstrated agglomerated nanosheet-like structures with uniform elemental distribution and polycrystalline nature. The photocatalytic activity of the ZV NPs was evaluated through the degradation of Methylene blue dye under visible light irradiation. The prepared samples achieved the highest degradation efficiency of 59.7%, attributed to its reduced crystallite size, lower electron–hole recombination rate, and enhanced generation of reactive oxygen species (ROS). The degradation mechanism was further investigated by studying the influence of catalyst dosage, dye concentration, pH, and scavengers. Electrochemical studies further revealed the promising paracetamol sensing capability of the synthesized nanoparticles, achieving a low limit of detection (LOD) of 0.837 µM. These results highlight the dual functionality of the synthesized Zn <sub>2</sub> V <sub>2</sub> O <sub>7</sub> nanoparticles as efficient photocatalysts for environmental remediation and as highly sensitive electrochemical sensors. </p>