Preparation of tetrapod-like ZnO whiskers from waste hot dipping zinc

Abstract

Large and uniform tetrapod-like ZnO whiskers (T-ZnO) were prepared from waste hot dipping zinc by vapor oxidation and examined by means of X-ray diffraction and ICP-AES analysis and scanning electron microscope. The products are pure hexagonal wurtzite crystals with tetrapod shape and edge size of center body 5–6 µm and needle length of 100–130 µm. The size and shape of ZnO particles are fully controlled by the growth conditions and T-ZnO can be obtained only at 850–1000 °C and total gas flow rate ranging from 40 to 250 L · h⁻¹ in which the size of the T-ZnO particles varies slightly with temperature. The process of the formation of T-ZnO is that T-ZnO may nucleate at the initial stage with a complete tetrapod shape and develop to the large size, but not the process of preferential growth of octahedral nuclei and subsequent growth of the needles. The experiment presents a new method to prepare T-ZnO economically by using the waste hot dipping zinc.

Keywords

waste hot dipping zinc / tetrapod-like ZnO whisker / preparation / crystal morphology