Wen Xiaogang, Fang Yueping, Pang Qi, Yang Chunlei, Wang Jiannong, Ge Weikun, Wong Kam Sing, Yang Shihe
Department of Chemistry, Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
J Phys Chem B. 2005 Aug 18;109(32):15303-8. doi: 10.1021/jp052466f.
In situ growth of ZnO nanobelt arrays from and on zinc substrates (foils and microparticles) has been accomplished by controlled thermal oxidation in the presence of oxygen. The nanobelts grow approximately perpendicular to the Zn substrate surface along the 110 direction of ZnO, which has a thickness of approximately 3-4 nm, a width tapering from about 50 to 300 nm, and a length of approximately 10-20 mum. On the basis of the structural analysis and kinetic studies, a tip-growth mechanism is proposed, which underlines the transport of Zn from the substrate to the growing tip. The ratio of UV to green photoluminescent emissions of the as-synthesized ZnO nanobelt arrays could be controlled by varying the reaction conditions. Sharp UV stimulated emission peak is also observed at moderate threshold excitation intensity ( approximately 0.7 mJ/cm(2)) showing the high quality of the ZnO nanobelts. The ZnO nanobelts array has also been tested for sensing NH(3) gas, and high sensitivity, reversibility, and rapid response have been demonstrated.
通过在氧气存在下进行可控热氧化，已实现从锌基底（箔片和微粒）上原位生长ZnO纳米带阵列以及在锌基底上生长ZnO纳米带阵列。纳米带沿ZnO的110方向大致垂直于Zn基底表面生长，其厚度约为3 - 4 nm，宽度从约50 nm逐渐变窄至300 nm，长度约为10 - 20μm。基于结构分析和动力学研究，提出了一种尖端生长机制，该机制强调了锌从基底向生长尖端的传输。通过改变反应条件，可以控制合成的ZnO纳米带阵列的紫外光与绿色光致发光发射的比率。在中等阈值激发强度（约0.7 mJ/cm²）下还观察到尖锐的紫外受激发射峰，这表明ZnO纳米带具有高质量。还对ZnO纳米带阵列进行了NH₃气体传感测试，并展示出高灵敏度、可逆性和快速响应。
