Improved Photocatalytic Activity of ZnO through Lanthanide Oxide Modification

Author : Gabriela-Antoaneta Apostolescu

Abstract : This study presents the synthesis and evaluation of ZnO nanostructures modified with lanthanide oxides (CeO2 , La2 O3 , and Gd2 O3 ) for the photocatalytic degradation of ceftriaxone in aqueous solutions. The materials were prepared via a sol–gel method to ensure homogeneous dopant dispersion, and their structural and functional properties were characterized. Photocatalytic activity under UV irradiation was assessed at an optimal catalyst loading of 0.05 g·L-¹, with degradation following pseudo-first-order kinetics, indicating that the process is governed by surface-mediated reactions. Among the investigated systems, CeO2 /ZnO showed the highest photocatalytic efficiency (91,3%), outperforming pure ZnO and the samples modified with La2 O3 or Gd2 O3 . This improvement is attributed to more effective charge-carrier separation, enhanced formation of reactive oxygen species, and the establishment of ZnO–CeO2 heterojunctions that promote electron transfer. These results show that modifying ZnO with f-block oxides—especially CeO2 —offers an effective route to significantly enhance its photocatalytic efficiency for removing antibiotic contaminants from wastewater.

Keywords : Ceftriaxone removal, lanthanide-doped ZnO, photocatalytic degradation, sol–gel synthesis

Conference Name : International Conference on Green Catalysis and Sustainable Chemical Processes (ICGCSCP-26)

Conference Place : Virtual, Crete, Greece

Conference Date : 15th Jun 2026