Formation of ZnO nanoparticles by laser ablation in neat water

► The sizes and shapes of the nanoparticles are affected only slightly by the ablation time and fluence. ► The nanoparticles formed by ablation of 355 nm have a distinctive wire-shape with a small diameter. ► The photofragmentation induced by irradiation of 355 nm controls sizes and shapes of the nanoparticles.