Insight into lanthanides REVO4 (RE = Ce, Pr, Nd): a comparative study on RE-site variants in the electrochemical detection of metronidazole in environmental samples

Abstract

The antibiotic drug metronidazole (MNZ), which is derived from nitroimidazole, is frequently used to treat a wide range of illnesses in both humans and domestic animals that are brought on by anaerobic bacteria and protozoa. But due to its high level of danger, possible genotoxic, carcinogenic, and mutagenic side effects, and problems of pharmaceutical waste disposal in the environment, this medicine is prohibited on a number of continents. Rare earth metal vanadates (REVO₄, RE = Ce, Pr and Nd) were synthesized by a facile hydrothermal method as they have an effective charge transfer ability and significant catalytic behavior towards the detection of pharmaceutical pollutants. In this work, the structural parameters of three sustainable REVO₄ electrocatalysts, with variation in RE site in the tetragonal forms are investigated by X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy. Sustainable electrocatalysts, such as CeVO₄, PrVO₄ and NdVO₄, show a tetragonal phase with space group I4₁/amd and a single crystalline structure. A CeVO₄ modified glassy carbon electrode (GCE) exhibits higher electrochemical activity than electrodes modified with PrVO₄ and NdVO₄. MNZ was detected using CeVO₄/GCE with a wide linear range of 0.02–75 μM, a low detection limit of 4.5 nM, good stability, and selectivity. Additionally, MNZ in actual water samples can be examined using the constructed CeVO₄/GCE electrode. A practical technique to manufacture high-efficiency CeVO₄-based electrode materials is presented in this work.