Titanium dioxide Sol–Gel/Zinc oxide Sol–Gel and Titanium dioxide Sol–Gel/powdered Zinc Oxide-coated clay beads in photocatalytic reactor

Document Type : Research Paper

Authors

1 Faculty of Ocean Engineering Technology, University Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia

2 Unidad Académica Preparatoria, Plantel II, Universidad Autónoma de Zacatecas, Zacatecas, Zac 98068, México

Abstract

Nowadays, immobilized photocatalyst clay beads have attracted considerable research interest due to their outstanding properties, including enhanced stability, easy recovery and reuse, and reduced secondary pollution. In this study, novel titanium dioxide/zinc oxide composites were synthesized via the sol–gel method and immobilized on clay beads using the dip-coating process. Various titanium dioxide/zinc oxide ratios were used to obtain different composites. For the immobilization procedure, four titanium dioxide/zinc oxide layers were coated on clay beads, dried in the oven at 100°C for 30 min, and subsequently calcined at 2°C/min up to 500°C. The coated beads were characterized using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). Photocatalytic degradation experiments were conducted to test their performance using methylene blue as a model pollutant. The highest methylene blue degradation efficiency was achieved with pure titanium dioxide-coated clay beads. All titanium dioxide/zinc oxide composites maintained their photocatalytic performance after five consecutive recyclability experiments. This work aims to demonstrate a reproducible, scalable, and economic immobilization procedure for single and composite photocatalysts on clay beads with outstanding photocatalytic performances for wastewater treatment.

Graphical Abstract

Titanium dioxide Sol–Gel/Zinc oxide Sol–Gel and Titanium dioxide Sol–Gel/powdered Zinc Oxide-coated clay beads in photocatalytic reactor

Keywords

Main Subjects

References

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Advances in Environmental Technology
Volume 12, Issue 3
July 2026
Pages 328-340

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History

  • Receive Date: 29 May 2025
  • Revise Date: 09 May 2026
  • Accept Date: 12 May 2026

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