Tapered ZnO Whiskers: {<it>hkil</it>}-Specific Mosaic Twinning VLS Growth from a Partially Molten Bottom Source

• Main Authors: Chen Shuei-Yuan, Huang Bang-Hao, Shen Pouyan
• Format: Article
• Language: English
• Published: SpringerOpen 2009-01-01
• Series: Nanoscale Research Letters
• Subjects: ZnO; Whiskers; Pulsed laser ablation; VLS; Photoluminescence
• Online Access: http://dx.doi.org/10.1007/s11671-009-9273-2

<p>Abstract</p> <p>Zn particulates overlaid with wurtzite (W)-type ZnO condensates having nearly orthogonal <inline-formula><graphic file="1556-276X-4-503-i1.gif"/> </inline-formula> and <inline-formula> <graphic file="1556-276X-4-503-i2.gif"/> </inline-formula> facets were found to self-catalyze unusual tapered W-ZnO whiskers upon isothermal atmospheric annealing, i.e., thermal oxidation, at 600 &#176;C. Analytical electron microscopic observations indicated that such whiskers formed tapered slabs having mosaic <inline-formula> <graphic file="1556-276X-4-503-i3.gif"/> </inline-formula> and <inline-formula> <graphic file="1556-276X-4-503-i4.gif"/> </inline-formula> twinned domains. The tapered whiskers can be rationalized by an alternative vapor&#8211;liquid&#8211;solid growth, i.e., {<it>hkil</it>}-specific coalescence twinning growth from the ZnO condensates taking advantage of a partially molten bottom source of Zn and the adsorption of atoms at the whisker tips and ledges under the influence of capillarity effect. The tapered whiskers having strong photoluminescence at 391 nm and with a considerable flexibility could have potential applications.</p>