In this investigation, Ce4+-modified ZrO2 nanoparticles (Zr-x%Ce) were successfully synthesized by the

ultrasonic assisted hydrothermal method to overcome the weaknesses of ZrO2 (very large band gap, poor

visible light absorption) and expand the application range of the original ZrO2. The changes in structural

and morphological properties due to the doping level of Ce in ZrO2 were investigated using XRD patterns,

Raman scattering, SEM images, EDS, BET, and UV-Vis-DRS studies. XRD patterns showed that the Ce-

doped ZrO2 nanoparticles had monoclinic and tetragonal phases. The average nanoparticle size of ZrO2 and

Ce-doped ZrO2 is less than 30 nm. The Raman spectra confirmed the characteristic vibrational groups of the

ZrO2 monoclinic and tetragonal phases. The Zr-x%Ce nanoparticles have high purity, with uniform

distribution of Ce in the ZrO2 matrix, a relatively high surface area, average capillary diameter, and small

band gap energy of 2.812-3.062 eV. Based on the outstanding properties of Zr-x%Ce, it can be used as a

sustainable, efficient, economical, and environmentally friendly photocatalyst for the treatment of dyes in

industrial wastewater