<p>ZnO/ZnO₂ nanocomposite thin films were obtained by doping ZnO with silver using a cost-effective sol–gel spin coating technique to investigate the impact of Ag concentration on their physical properties. The nanocomposite thin films were prepared by introducing silver into a zinc oxide precursor solution made from zinc acetate dihydrate, with doping levels systematically varied from 0 to 5 wt%, and deposited on glass substrates. X-ray diffraction (XRD) analysis confirmed the retention of the hexagonal wurtzite ZnO structure with a dominant (220) orientation. The ZnO phase became more pronounced at Ag concentrations above 1.5 wt%, while minor traces of cubic ZnO₂ appeared at higher doping levels. Scanning electron microscopy (SEM) revealed a uniform surface morphology with grain size variations influenced by Ag incorporation. Optical characterization showed high transmittance (~80%) in the 350–1200 nm range, accompanied by a gradual reduction in the optical bandgap from 3.75 eV to 3.5 eV as Ag content increased. Electrical measurements indicated enhanced conductivity, which peaked at 3 wt% Ag. The optimal balance between transparency and conductivity was achieved at 0.5 wt% Ag. These films demonstrated multifunctional potential in photocatalysis, biomedicine, and optoelectronics due to their improved crystallinity, surface area, and reactivity.</p> Graphical Abstract <p></p>