Green Synthesis of Ce-doped ZnO Nanocomposites for Photocatalytic Degradation of Methylene Blue and Rhodamine B in Aqueous Solution

Document Type : Research Paper

Authors

1 Department of Chemical Engineering, Faculty of Interdisciplinary Sciences and Technologies, University of Bonab, Bonab, Iran

2 Department of Polymer Science and Engineering, Faculty of Interdisciplinary Sciences and Technologies, University of Bonab, Bonab, Iran

Abstract

In this study, ZnO photocatalysts doped with various weight percentages of cerium were synthesized using a green synthesis method and applied for the removal of dye pollutants, namely methylene blue and rhodamine B. The addition of Ce up to 3 wt.% led to a reduction in particle size, more uniform particle distribution, increased specific surface area, and improved structural and optical properties. However, increasing the Ce content to 5 wt. % resulted in particle aggregation, reduced surface area, and non-uniform distribution due to doping saturation and the incomplete incorporation of Ce into the ZnO lattice. Moreover, Ce doping also reduced the band gap energy, with values of 3.2 eV for pure ZnO and 2.95 eV for the ZnO doped with 3 wt. % Ce (ZnCe3). Among the samples, ZnCe3 exhibited the best performance, achieving 94.6% degradation of methylene blue and 93.9% of rhodamine B within 180 minutes. In addition, this high efficiency is attributed to the narrower band gap, higher surface area, uniform particle distribution, and enhanced electron–hole separation. Overall, the results demonstrate that doping ZnO with an optimal amount of cerium (3 wt. %) combined with green synthesis significantly enhances its photocatalytic efficiency in the degradation of organic dyes.

Keywords

Main Subjects

References

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Journal of Petroleum Research
Volume 35, 1404-4 - Serial Number 143
November and December 2025
Pages 162-179

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