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Tetrapod-shaped ZnO whiskers and microrods were synthesized in one crucible by thermal evaporation of Zn/C mixtures at 930 ℃ in air without any catalyst.The digital camera,optical microscopy,scanning electron microscopy,energy dispersive X-ray spectroscopy,and X-ray diffraction techniques were used to study the morphologies and crystal structures of these tetrapod-shaped ZnO microcrystals.The results show that these two types of ZnO tetrapods are grown at different heights within the same crucible.The legs of these tetrapod-shaped ZnO crystals are hexagonally faceted.Some tetrapod-shaped ZnO whiskers show hierarchical structures.A short button-like hexagonal ZnO microcrystal is observed at the triple junctions of some tetrapod-shaped ZnO whiskers.The tetrapod-shaped ZnO microrods are capped by two sets of hexagonal pyramids with two different groups of crystal planes for the surfaces.These two types of tetrapod-shaped ZnO microcrystals have different side faces and aspect ratio,which are believed to be the result of their different growth behaviors.The octa-twin model was used to discuss the different growth behaviors of these two types of ZnO tetrapods.The crystal planes of the legs and the pyramids were determined.
Tetrapod-shaped ZnO whiskers and microrods were synthesized in one crucible by thermal evaporation of Zn / C mixtures at 930 ° C in air without any catalyst. The digital camera, optical microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, and X- ray diffraction techniques were used to study the morphologies and crystal structures of these tetrapod-shaped ZnO microcrystals. The results show that these two types of ZnO tetrapods are grown at different heights within the same crucible. These legs of these tetrapod-shaped ZnO crystals are hexagonally-faceted. Home tetrapod-shaped ZnO whiskers show hierarchical structures. A short button-like hexagonal ZnO microcrystal is observed at the triple junctions of some tetrapod-shaped ZnO whiskers. The tetrapod-shaped ZnO microrods are capped by two sets of hexagonal pyramids with two different groups of crystal planes for the surfaces. these two types of tetrapod-shaped ZnO microcrystals have different side faces and aspect ratio, which are believed to be the result of their different growth behaviors. octa-twin model was used to discuss the different growth behaviors of these two types of ZnO tetrapods.The crystal planes of the legs and the pyramids were determined.