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采用脉冲激光沉积技术,在Si(111)衬底上成功制备出不同含量Na,Co共掺的ZnO薄膜.利用X射线衍射仪、原子力显微镜、荧光光谱仪以及四探针电阻率测试台对薄膜的结构、表面形貌和光电性质进行了表征.重点讨论了不同掺杂浓度对薄膜光电性质的影响.结果表明:Na,Co共掺没有改变ZnO的六角纤锌矿结构且掺杂导致薄膜仅有的的紫外发光峰出现红移.当Na,Co掺杂浓度分别为10%时,峰值最强且红移最明显,发光峰波长为397 nm,薄膜的电阻率最低,达到了8.34×10-1 Ω ·cm.深入讨论了
关键词:
脉冲激光沉积
1-x-yNaxCoyO薄膜')" href="#">Zn1-x-yNaxCoyO薄膜
光电性质
红移 相似文献
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在Y2 O3 ∶Eu3 + 体材料和纳米材料中 ,观察到紫外激发下处于S6格位的Eu3 + 的5D0 →7F1发射 ( 5 82nm)的强度 ,相对处于C2 格位的5D0 →7F0 发射 ( 5 80nm)的强度 ,随着激发波长在 2 0 0~ 3 0 0nm紫外区由长变短而增强。这一现象说明Y2 O3 ∶Eu3 + 中两种格位的电荷迁移带及基质激发的性质不同。光谱分解得出S6格位的电荷迁移带位于C2 格位电荷迁移带的高能侧 ,Y2 O3 基质倾向于向S6格位进行能量传递。与体材料相比 ,两种格位的电荷迁移带在纳米材料中都发生红移 ;相对于C2 格位的电荷迁移带 ,S6格位的电荷迁移带强度在纳米材料中比在体材料中明显降低 ,并对结果进行了讨论。 相似文献
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1 INTRODUCTION Hydrogen bond plays an important role in the fields of physics, biology and chemistry. It has cap- tured the interest of chemists for a long time and reports about its theory and experiment have been well represented[1~6]. Concerning its theoretical inves- tigations, most of the emphases are placed on the weak interaction energy of intramolecular hydrogen bond. But studies on its spectrum behavior are rela- tively rare. These years spectrum behavior led by hydrogen bond h… 相似文献
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Five optimized geometries of F-·(H2O)n (n = 1, 2) were obtained with ab initio calculation at the B3LYP/6-311++G** level.The accurate intermonomer interaction energy was calculated using the MP2 electron correlation correction as well as the basis set superposition error correction by the Boys-Bernardi "counterpoise" protocol.Natural bond orbital (NBO) theory was applied to quantify the relative strength of these interactions and account for their effects on the stability, structural and vibrational parameters of Fˉ·(H2O)n (n = 1, 2).It is shown that the charge transferring from the lone pair of F-1 to the σ*OH(…F) antibonding orbital is important.The results indicate the occupancy of σ*OH(…F) is increased (denoted Δσ*OH(…F)) and the ΔROH(…F) bond is leng- thened (denoted (ROH(…F)), leading to the red-shift and the red-shift values have linear correlation with both Δσ*OH(…F) and ΔROH(…F). 相似文献
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Power dependence of terahertz carrier frequency in a plasma-based two-color generation process 下载免费PDF全文
We conduct a frequency spectrum experiment to investigate terahertz(THz) emissions from laser-induced air plasma under different laser incident powers. The frequency spectra are measured using both air-biased-coherent detection and a Michelson interferometer. The red-shift of the THz pulse carrier frequency is observed as a response to increased pump power. These phenomena are related to plasma collisions and can be explained by the plasma collision model. Based on these findings, it is apparent that the tuning of the THz carrier frequency can be achieved through regulation of the pump beam. 相似文献
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Jiayu Long Jiankai Shan Yaxin Zhao Ying Ji Prof. Hongwei Tan Prof. Huiliang Wang 《化学:亚洲杂志》2021,16(17):2426-2430
Small organic compounds without any traditional fluorescent chromophores are generally non-emissive, and only very few are reported to emit weak blue fluorescence. Here we synthesized a non-traditional luminescent small organic compound N-(2,2,2-trifluoroethyl)acrylamide (TFAM) with dramatically enhanced and red-shifted photoluminescence by introducing a strong electron-withdrawing group into acrylamide (AM). Very impressively, TFAM emits cyan (472 nm) and yellow-green (560 nm) fluorescence in solutions and solid state, respectively. TFAM also shows aggregation-induced emission enhancement (AIEE) and excitation-dependent fluorescence (EDF) characteristics, as well as temperature and metal cations-responsive fluorescence. Theoretical calculations show that the introduction of electron-withdrawing group leads to a lower energy gap between the HOMO–LUMO energy levels in TFAM than in AM. And strong cooperative hydrogen bonds are formed in TFAM molecules, resulting in rigidification of molecular conformations. The study provides a strategy for preparing non-traditional luminescent compounds with enhanced and red-shifted photoluminescence. 相似文献