Efficient photocatalytic degradation of Rhodamine B dye by undoped and zinc doped zirconium dioxide NPs

Abstract

Undoped and Zinc-doped Zirconium Dioxide (ZrO₂) nanoparticles (NPs) were synthesized via the co-precipitation method, employing Zirconium (IV) Oxynitrate hydrate (ZrO₂N₂·xH₂O), Zinc Sulfate (ZnSO₄·7H₂O), and ammonia solution as precursor materials at room temperature. A comprehensive characterization of the structural, morphological, optical, and catalytic properties of the prepared samples was conducted using various techniques. Powder X-ray diffraction (PXRD) analysis revealed that the synthesized NPs exhibited a tetragonal phase structure, with crystallite sizes decreasing as doping concentration increased. Scanning electron microscopy (SEM) images confirmed the spherical shape of the NPs. Energy-dispersive X-ray spectroscopy (EDX) verified the presence of Zr, O, and Zn elements with high purity. Raman spectroscopy corroborated the tetragonal structure of the synthesized ZrO2 NPs. Ultraviolet–visible (UV–Vis) spectroscopy studies determined the cutoff wavelengths, while Tauc plot enabled the calculation of band gap energies. Fourier transform infrared spectroscopy (FTIR) confirmed the functional groups present in the synthesized samples. Photoluminescence spectroscopy provided evidence of defects and charge carrier recombination processes. The catalytic efficacy of the synthesized ZrO₂ NPs was demonstrated through the degradation of Rhodamine B dye under visible and UV light.