Band gap tuning of Ce doping in Zn:Zr system for enhanced visible light-driven photocatalysis

The environmental threat posed by industrial dyes necessitates the development of efficient photocatalytic systems for their degradation. This study focuses on the Ce-doped Zn:Zr system as an innovative solution for visible-light-driven photocatalytic degradation of textile dyes offering significant environmental and industrial benefits. The Ce-doping effect on the photocatalytic efficiency of the Zn:Zr system was investigated. Both undoped and Ce-doped Zn:Zr systems exhibited hexagonal nanostructures with high atomic percentages of Zn, while Ce was incorporated at lower percentages. X-ray diffraction confirmed the unaltered hexagonal ZnO, tetragonal, and monoclinic ZrO₂ crystal structures in the systems. The peak broadening in the Ce-doped samples indicates successful doping. Even the tiniest alteration in band gap resulted in a dramatic increase in methylene blue dye degradation up to 98.4%, significant at p < 0.05. This enhanced efficiency is attributed to the heterogeneous pairing mechanism which improves charge carrier separation with superoxide anions and singlet oxygen identified as the primary reactive species. The findings demonstrate the applicability of band gap engineering in organic pollutant degradation and highlight the potential of Ce-doped Zn:Zr systems as a cost-effective and energy-efficient solution for industrial wastewater management.