Novel spongelike nanostructured ZnO films: Properties and applications

► Nanostructured Zn was grown at room-temperature via vapor deposition. ► Zn was thermally oxidized in ambient air for synthesizing spongelike ZnO films. ► Morphological, structural, optical and functional properties were assessed. ► Polycrystalline, transparent, light-sensitive nanostructured films were obtained. ► Spongelike ZnO films are promising for sensing and photovoltaic applications.