Journal of Saudi Chemical Society (May 2023)

Band structure tuning of ZnO/CuO composites for enhanced photocatalytic activity

  • Khalida Mubeen,
  • Afshan Irshad,
  • Akif Safeen,
  • Uzma Aziz,
  • Kashif Safeen,
  • Tayyaba Ghani,
  • Kamran Khan,
  • Zulfqar Ali,
  • Ihsan ul Haq,
  • Attaullah Shah

Journal volume & issue
Vol. 27, no. 3
p. 101639

Abstract

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The toxic dye pigments, even in small quantities, can damage ecosystems. Removing organic, inorganic, and microbiological contaminants from wastewater via heterogeneous photocatalysis is a promising method. Herein, we report the band structure tuning of ZnO/CuO nanocomposites to enhance photocatalytic activity. The nanocomposites were synthesized by a chemical approach using step-wise implantation of p-type semiconductor CuO to n-type semiconductor ZnO. Various characterization techniques such as X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray analysis (EDX) and UV spectroscopy were used to investigate the crystal structure, surface morphology, elemental composition and optical properties of the synthesized samples. As the CuO content increased from 10% to 50% in ZnO/CuO nanocomposites, the optical bandgap decreased from 3.36 to 2.14 eV. The photocatalytic activity of the samples was evaluated against the degradation of methylene blue (MB) under visible irradiation. Our study demonstrates a novel p–n junction oxide photocatalyst based on wt. 10% CuO/ZnO with superior photocatalytic activity. Effectively 66.6% increase in degradation rate was achieved for wt. 10% CuO/ZnO nanocomposite compared to pure ZnO nanoparticles.

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