H. Hou et al. /Solid State Sciences 7(2005)45-51 (0111 (0110 Fig 3. FE-SEM and SAED micrographs of Zno tubular whiskers(pH= 10, Fig 4 SEM of the as-synthesized Zno tubular whiskers (pH= 10 140.C, 12 h).(a) The FE-SEM image on the surface of hollow Z 140C, 12 h).(a) The obliq Wended tubular Zno whisker.(b)The whisker. (b) The SAED pattern of the tubular Zno whisker. (c, d)The rupture tubular Zno whisker.(c)The mid-broken tubular Zno whiskers. FE-SEM image on the open end of the tubular Zno whisker. (e)The (d) The split tubular ZnO whisker. FE-SEM on the close end of an individual tubular Zno whisker (f)The FE-SEM image on the top of the tubular Zno whisker the end facet of tubular Zno prismatic whiskers is hexag- onal, smooth and well-defined crystallographic. The hexag onal concave groove with the width of 300 nm was clearly showed between the top-viewed hexagonal Zno whisker and the hexagonal inset hollow cavity. The inset hexagonal hol low cavity, with the width of I um and angles about 1200, has smooth, well-defined inner crystallographic facets. At the end of the hollow cavity, six identical trapezoid bevels connect the clearly ended hexagon to the uniform inner cav ity facets The oblique open-ended, the ruptur, the middle-broken the split tubular Zno whisker can be found in the as wn product, as showing in the SEM images of Fig. 4, respectively, all confirming their hexagonal hollow nature. Comparatively, in our experiment, the system of pH=8 at 110C for 12 h produce epitaxial Zno whiskers when using structure-directing agent CTAB. Fig. 5 shows the com- prehensive image of ZnO epitaxial whiskers, which demon- strates that the sample consists of a large scale of epi- taxial whiskers with smooth and symmetrically hexagonal shapes and well-knit structure. The yield of the Zno ep taxial whiskers synthesized by this hydrothermal method Further morphology description of the Zno epitaxial Fig. 5. SEM image of the as-synthesized ZnO epitaxial whiskers(pH=8, whiskers was accomplished using FE-SEM as shown l10°C,12h)H. Hou et al. / Solid State Sciences 7 (2005) 45–51 47 Fig. 3. FE-SEM and SAED micrographs of ZnO tubular whiskers (pH = 10, 140 ◦C, 12 h). (a) The FE-SEM image on the surface of hollow ZnO whisker. (b) The SAED pattern of the tubular ZnO whisker. (c, d) The FE-SEM image on the open end of the tubular ZnO whisker. (e) The FE-SEM image on the close end of an individual tubular ZnO whisker. (f) The FE-SEM image on the top of the tubular ZnO whisker. the end facet of tubular ZnO prismatic whiskers is hexag￾onal, smooth and well-defined crystallographic. The hexag￾onal concave groove with the width of 300 nm was clearly showed between the top-viewed hexagonal ZnO whisker and the hexagonal inset hollow cavity. The inset hexagonal hol￾low cavity, with the width of 1 µm and angles about 120◦, has smooth, well-defined inner crystallographic facets. At the end of the hollow cavity, six identical trapezoid bevels connect the clearly ended hexagon to the uniform inner cav￾ity facets. The oblique open-ended, the ruptur, the middle-broken and the split tubular ZnO whisker can be found in the as grown product, as showing in the SEM images of Fig. 4, respectively, all confirming their hexagonal hollow nature. Comparatively, in our experiment, the system of pH = 8 at 110 ◦C for 12 h produce epitaxial ZnO whiskers when using structure-directing agent CTAB. Fig. 5 shows the com￾prehensive image of ZnO epitaxial whiskers, which demon￾strates that the sample consists of a large scale of epi￾taxial whiskers with smooth and symmetrically hexagonal shapes and well-knit structure. The yield of the ZnO epi￾taxial whiskers synthesized by this hydrothermal method is above 95%. Further morphology description of the ZnO epitaxial whiskers was accomplished using FE-SEM as shown in Fig. 4. SEM images of the as-synthesized ZnO tubular whiskers (pH = 10, 140 ◦C, 12 h). (a) The oblique open-ended tubular ZnO whisker. (b) The rupture tubular ZnO whisker. (c) The mid-broken tubular ZnO whiskers. (d) The split tubular ZnO whisker. Fig. 5. SEM image of the as-synthesized ZnO epitaxial whiskers (pH = 8, 110 ◦C, 12 h)