Template-free sonochemical synthesis of flower-like ZnO nanostructures

• A facile and template-free sonochemical method to fabricate flower-like ZnO nanostructures was proposed.
• The flower-like ZnO nanostructures follow the ingrowth of ZnO from the matrix of Zn(OH)2 crystals.
• The flower-like ZnO nanostructures are also expected to explore their application in the field of nano-electronic devices.

Flower-like ZnO nanostructures have been successfully synthesized via a facile and template-free sonochemical method, using zinc acetate and potassium hydroxide as reactants only. The as-synthesized flower-like ZnO nanostructures were composed of nanorods with the width of ∼300–400 nm∼300–400 nm and the length of ∼2–3 μm∼2–3 μm. The structures, morphologies and optical properties of the as-prepared products were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscopy, UV-Vis spectrophotometry and Raman-scattering spectroscopy. A plausible formation mechanism of flower-like ZnO nanostructures was studied by SEM which monitors an intermediate morphology transformation of the product at the different ultrasonic time (t=80,90,95,105, and 120 mint=80,90,95,105, and 120 min).