摘要
通过改进传统水热法的密闭、高压的条件,在非密闭、常压环境下在氧化铟锡玻璃衬底上自组装生长了取向高度一致并且分散性好的ZnO纳米棒阵列。首先将乙酸锌溶胶旋涂到氧化铟锡玻璃衬底上,经热处理得到致密的ZnO纳米晶薄膜,然后将其垂直放入前驱体溶液中通过化学溶液沉积生长得到ZnO纳米棒阵列。室温条件下,对样品进行了SEM和XRD的测试,表明生成的氧化锌纳米棒阵列沿c轴取向,实现了定向生长,且纳米棒结晶较好,为六方纤锌矿结构,直径约为40nm,长度达到微米量级。室温下的吸收光谱表明,由此方法得到的纳米棒纯度较高,有强的紫外吸收。室温下,观测到了该有序ZnO纳米棒阵列在387nm处强的窄带紫外发射,半高宽小于30nm,在468nm处还有一强度较弱的蓝光发射峰。
Improving on the sealing and high pressure conditions of traditional hydrothermal method, vertical ZnO nanorod arrays were synthesized on indium tin oxide substrate by employing Zn（NO3 ）2 · 6H2O, （CH2）4N6 as the starting materials in the presence of polyethylenimine（PEI） at ambient pressure and low temperature （92°）. Between the substrate and the nanorods, a layer of ZnO flim was prepared as buffer layer and seed layer. The ZnO film was gained by spin-coating zinc acetate solution on indium tin oxide substrate, then annealed at 350 ℃ for 20 min, which can make zinc acetate decompose into zinc oxide. The zinc acetate spin-coating and decomposition procedure was carried out twice to ensure a complete and uniform coverage of ZnO seeds. The second layer was annealed at 500 ℃ for 30 min. Different spin-coating speeds were adopted, one was 2 500 r · min^-1 , and the other was 5 000 r · min^-1. XRD result indicated that the seed layer with 5 000 r · min^-1 has better alignment than the layer with 2 500 r · min^-1. The aligned seeds with 5 000 r · min^-1 show only a （002） reflection, indicating their complete e-axis texturing, whereas the spin-coated seeds give a powder pattern because they rest at all angles on the substrate. SEM result shows that the layer is made up of grains with an the average size of about 30 nm. Well-aligned ZnO nanorod arrays were synthesized by putting the substrate with ZnO seeds into the precursor solutions vertically for one hour. The nanorod arrays were taken out and rinsed with clean ethanol and pure-water for several times, blown dry with a stream of nitrogen, then annealed at 400 ℃ for 30 min in order to wipe off the organic solvent. At room-temperature, the SEM and XRD were measured. SEM results indicate that the crystal structure of most of ZnO nanorods is hexagonal wurtzite crystallographic phase structure, mainly vertical to the substrate. ZnO nanorods have good crystallization, the diameter of the rods is around 40 nm, and the length is above micrometer. The XRD results showed the nanorod arrays have （002） and （004） angles, and the （002） is quite strong. Absorption spectra of the nanorod arrays shows ZnO essence absorption and strong ultraviolet absorption, indicating that ZnO has good quality. Optical properties were studied, and the excitation spectra of the nonorod arrays showed a strong and narrow peak at 387 nm with FWHM smaller than 30 nm and a weak blue peak.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2008年第10期2249-2253,共5页
Spectroscopy and Spectral Analysis
基金
国家"863"计划(2006AA03Z0412)
国家自然科学基金项目(10774013
60576016)
教育部博士点基金项目(20070004024)
博士点新教师基金项目(20070004031)
北京市科技新星计划(2007A024)
教育部留学回国科研启动基金项目
校基金项目(2005SM057)
北京交通大学客座研究员基金项目(48107)资助
作者简介
刘然,女,1981年生．北京交通大学光电子技术研究所硕士研究生
通讯联系人 e-mail：zhangt2003@126．com
