Journal of Ultrafine Grained and Nanostructured Materials

Journal of Ultrafine Grained and Nanostructured Materials

Engineering Photocatalytic TiO₂/CuWO₄ Coatings: The Synergistic Effect of Oxidants on Heavy Metal Remediation

Document Type : Research Paper

Authors
Hamed Bahramian
Arash Fattah-alhosseini
Minoo Karbasi
Bu-Ali Sina University, Department of Materials Engineering, Faculty of Engineering, Hamedan, Iran
10.22059/jufgnsm.2025.02.03
Abstract
A highly active TiO₂/CuWO₄ heterostructure coating for Cr⁶⁺ photoreduction was developed through PEO and hydrothermal post-treatment. Characterizations such as FESEM, GXRD, AFM and wettability, revealed that nano-sized CuWO₄ integration transforms the morphology, producing a hierarchical, microporous base with uniformly distributed particles and a super-hydrophilic, rough surface for improved accessibility. Oxidant screening revealed that both radical (〖SO〗_4^(⦁-), 〖HO〗^⦁) and non-radical species are critical to the mechanism. Peroxydisulfate (PDS) achieved the highest synergy (synergistic factor= 0.9) via sulfate radical generation, significantly outperforming peroxymonosulfate (PMS) and the ineffective H₂O₂. This study proposes a dual-pathway mechanism and introduces a durable, scalable photocatalytic coating solution for environmental cleanup.
Keywords
Cr photoreduction
Oxidants
plasma electrolytic oxidation
hydrothermal
TiO₂/CuWO₄ Coatings
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Journal of Ultrafine Grained and Nanostructured Materials
Volume 58, Issue 2
December 2025
Pages 152-160

  • Receive Date 11 November 2025
  • Revise Date 22 November 2025
  • Accept Date 23 November 2025