Effect of processing parameters on structural and optical properties of CeO2 nanoparticles for the removal of crystal violet dye

The present work reports the synthesis of CeO2 nanoparticles (NPs) via chemical route by optimizing synthesis parameters such as solvent, capping agent, and calcination temperature. The prepared samples were characterized via X-ray diffraction (XRD), transmission electron microscopy, Fourier-transformed infrared spectroscopy, Raman spectroscopy, and UV-visible spectroscopy for structural, morphological, and optical studies. The XRD results confirmed the formation of cubic fluorite structured CeO2 with an average crystallite size similar to 5-11 nm. The enhancement in crystallite size was observed along with agglomerated irregular spherical-shaped NPs after calcination at higher temperatures. The use of capping agent (thioglycerol; TG) led to the reduced aggregation of NPs. With the help of UV-visible spectroscopy, a redshift was observed in the maximum absorbance peak as an effect of calcination. The NPs synthesized in ethanol as solvent exhibited better degradation efficiency for crystal violet dye than that synthesized in water medium due to high surface to volume ratio and surface functionalities inducing more active sites for the creation of electrons hole pair. It was observed that (TG) capped samples exhibited more photocatalytic activity toward the degradation of crystal violet dye than uncapped samples due to less agglomeration of particles. Furthermore, in the presence of the optimum amount of H2O2 the catalytic activity was achieved up to 97% within 90 min only.

Automated summary

This work successfully synthesized CeO2 nanoparticles by optimizing synthesis parameters and characterized them using various techniques for structural, morphological, and optical studies. The addition of a capping agent reduced particle aggregation, leading to enhanced photocatalytic activity, with nanoparticles synthesized in ethanol exhibiting higher degradation efficiency.