Comparative study of zirconium-zinc oxide thin films on ceramic and glass substrates: Structural, optical, and photocatalytic properties

Abstract

This study investigates the structural, optical, and photocatalytic properties of zirconium-doped zinc oxide (Zr) thin films deposited on ceramic and glass substrates. X-ray diffraction (XRD) analysis revealed that all samples exhibited a polycrystalline wurtzite structure, with grain sizes ranging from 25 to 43 nm for ceramic substrates and 19 to 32 nm for glass substrates. UV–visible absorbance measurements indicated that Zr films absorbed visible light around 410 nm, with the band gap widening to 2.93 eV on ceramic substrates. Scanning electron microscopy (SEM) showed that Zr doping significantly affected the morphology of thin films, resulting in rougher surfaces and larger grains on ceramic substrates. Photocatalytic tests demonstrated that the 5 wt% Zr on DD1Z ceramic achieved a degradation efficiency of 61.44 % for orange II dye after 5 h of UV irradiation. In contrast, Zr on ceramic substrates achieved only 18.56 %, and the bare DD1Z substrate reached just 4.02 %. These findings highlight the superior photocatalytic performance of Zr on ceramic substrates, indicating their potential for advanced water purification technologies. The mechanism of photolysis was investigated using hole/radical scavengers, revealing that Zr-ZnO networks enhance the adsorption of hydroxyl ions on the surface. This acts as a trap site, reducing hole/electron pair recombination and thus increasing activity and photodegradation efficiency.