Publication date: 8 July 2026
Source: Journal of Nano Research Vol. 93
Author(s): Toubane Mahdia, Haouanoh Djedjiga, Kacel Tawous, Chabira Fares, Bessaad Asma, Katia Ayouz, Siah Hocine, Benhaoua Fayrouz
Three different ZnO thin-film morphologies, nanowires (NWs), nanocubes (NCs), and nanopolyhedra (NPs), were fabricated using the sol–gel dip-coating method. The effects of the substrate type (glass and Indium Tin Oxide (ITO)) and dopants (Al, Ag, and F) on the structural, morphological, optical, electrical, and photocatalytic properties were investigated. X-ray diffraction and Raman spectroscopy confirmed that all films crystallized in a hexagonal Wurtzite structure, with the formation of secondary phases, including ZnF₂, Ag₂O₃, Al₂O₃, and Zn(OH)₂, observed for films deposited on ITO substrates. SEM analysis showed that both dopants and substrates strongly influence the surface morphology of ZnO films. Al, Ag, and F doping led to nanowire, nanopolyhedral, and nanobrick structures respectively, while films deposited on glass exhibited spherical morphologies. Surface roughness ranged from 16.5 to 34.1 nm. Al-doped films on ITO exhibited excellent optoelectronic performance (transmittance = 92.07%, conductivity = 3.85 × 10² (Ω·cm)⁻¹). Ag-doped ZnO films showed the highest photocatalytic activity, achieving up to 98% dye degradation within 180 min.
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