Formation of tetrapod ZnO nanowhiskers and its optical properties

Abstract Nanopowder containing ZnO nanowhiskers and nanoparticles was synthesized by the oxidation of Zn vapor, at temperatures from 1050 to 1450 °C in a flow of Ar and O 2 gas mixture. The morphology and structure of the nanowhiskers were dependent on the synthesis parameters such as evaporation temperature and the gas pressure. The nanowhiskers formed had a tetrapod shape with needle-like feet that become shorter and fatter on increasing temperature under a certain pressure range. The amount of Zn phase inside the nanowhiskers increased with increasing temperature. The Zn phase melted at temperature of 420 °C, which was confirmed by differential scanning calorimetry (DSC). The nanopowders showed strong sintering activity after they were pressed. The far infrared light was intensely absorbed by the ZnO tetrapod nanowhiskers.