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采用共沉淀法制备出不同掺杂浓度的Zn1-xFexO(0.00≤x≤0.10)粉末样品,研究掺杂浓度的不同对其结构、光学性质以及室温铁磁性的影响。采用X射线衍射仪、红外光谱仪、紫外-可见分光光度计、荧光光谱仪、振动样品磁强计对样品的结构、光学性质和磁性进行测试分析。结果表明:所有Zn1-xFexO样品都具有单一六方纤锌矿结构,没有出现第二相杂质。对紫外波段吸收率高达95%,掺Fe后可见光波段的吸收率与纯ZnO相比有明显提高,掺杂使得带隙宽度Eg由纯ZnO的3.20eV减小到3.11eV。样品光致发光主要有397nm的紫外发射和450,466nm处的蓝光发射,Fe的掺入降低了ZnO的发光强度,但并不影响其发光峰位。样品显示明显的室温铁磁性,磁性随掺杂浓度升高而减弱。 相似文献
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利用溶胶凝胶法制备了纳米结构的Cu掺杂ZnO基稀磁半导体,通过X射线衍射分析表明,样品为纯相ZnO纤锌矿结构,磁性测量表明样品在室温下呈室温铁磁性,铁磁性来源为氧化锌晶格中的缺陷与Cu2+离子之间的交换作用。室温光致发光(PL)谱观察到紫外带边和可见光区两个发射峰,且随着Cu掺杂量增加,紫外峰淬灭,可见峰发射增强。 相似文献
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采用共沉淀制备了稀土Ce掺杂ZnO光催化剂;利用X射线衍射(XRD)、扫描电子显微镜(SEM)等对光催化剂进行表征;考察了不同NaOH用量制备的催化剂光催化对亚甲基蓝脱色降解性能的影响。结果表明,ce的掺杂有利于抑制光生电子-空穴的复合,显著提高ZnO的光催化性;NaOH用量和Ce掺杂量对光催化剂的微观形貌和光催化活性有较大影响;制备过程中金属离子总量(Ce^3++Zn^2+)与OH-摩尔比为1:2.5,掺杂量为2%(摩尔分数)时,制备的催化剂主要微观形貌为具有层状微球结构,光催化性能良好。 相似文献
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Cr掺杂ZnO薄膜晶体结构及光学性能的研究 总被引:1,自引:0,他引:1
采用磁控溅射法在载玻片上制备了不同Cr掺杂浓度的ZnO薄膜,并对其紫外发光性能做了初步研究.XRD结果表明,所制备的样品具有纤锌矿结构,呈c轴择优取向生长;透射谱表明,改变Cr掺杂浓度可以使ZnO薄膜的吸收边向短波方向移动,并且薄膜的禁带宽度连续可调;光致发光(PL)谱表明,所有样品的PL谱由发光中心位于370nm的紫外发光峰组成,且该峰的峰位蓝移,与吸收边缘移动的结果吻合.2.0%(原子分数,下同)的Cr掺杂可以提高ZnO的紫外发光强度,而过量的Cr掺杂反而会降低其紫外发光强度. 相似文献
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采用射频磁控溅射法在Si(100)衬底上沉积过渡族金属Mn掺杂的ZnO薄膜。将5%及7%原子比的MnO,与ZnO粉末充分混合后,加压制成靶材,通过改变溅射过程中的气氛和衬底温度沉积了Zn1-xMnxO薄膜。x射线衍射和场发射扫描电镜的分析表明:掺入≤7%的Mn原子不会改变薄膜的晶体结构,薄膜呈高度(002)晶面择优取向;薄膜表面均匀致密,颗粒尺寸约为30hm;Mn的掺入使薄膜的电学性能明显改善,但氧分压的使用或者Mn含量过大又会使薄膜的电阻率增加。 相似文献
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《Journal of Experimental Nanoscience》2013,8(9):682-689
Simple and low cost solution synthesis method was used to synthesise ZnO nanorods. Dodecyl benzene sulfonate was used to control the growth process and monodispersed nanorods with diameters in the range of 25 to 44 nm were obtained. X-ray diffraction, transmission electron microscopy and high resolution transmission electron microscopy measurements demonstrate the structure and morphology of the products. Laser power- and temperature-dependent photoluminescence (PL) experiments confirm the good ultraviolet emission characteristics. Short exciton lifetime feature relevant to thin nanorods was examined by time-resolved PL. Good optical quality and the size characteristics of the obtained products are discussed. 相似文献
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Fe-doped ZnO was successfully fabricated by thermal in-diffusion of Fe into ZnO crystals. X-ray absorption near edge structure (XANES), photoemission and cathodoluminescence (CL) spectroscopy have been combined to examine the Fe diffusion and its effects on the electronic and optical properties of the crystal. Depth-resolved CL demonstrates that Fe in-diffusion occurs to at least 4 μm depth and results in intense green luminescence, whereas the undoped crystal exhibits only the ZnO near-band-edge emission. XANES and valence-band photoemission show that Fe is incorporated as Fe2+/3+ ions on substitutional Zn sites. The results suggest that the variation in the CL properties is due to a change in the oxygen vacancy charge state as a result of electron transfer from Fe. 相似文献
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刘翠萍 《材料科学与工程学报》2010,28(4)
采用共沉淀法制备了纯纳米ZnO和掺铁纳米ZnO,并用X射线衍射光谱进行了表征。用紫外灯作为光源,甲基橙溶液为光催化反应模型降解物,研究了ZnO及掺铁ZnO的光催化性能,并考察了前驱体焙烧温度、铁掺杂量、底物浓度、光照时间以及pH对降解率的影响。结果表明,掺杂铁离子提高了ZnO的光催化活性,400℃热处理的掺杂铁0.5%(质量比)的ZnO的光催化性能最好;当甲基橙初始浓度为5mg/L,光照时间3h,掺杂铁0.5%(质量比)的ZnO粉末对甲基橙的降解率达到84%;掺铁纳米ZnO在弱酸性条件下的催化效果比碱性条件下更好。 相似文献
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Fe-doped ZnO dilute magnetic semiconductor (DMS) nanowire arrays were fabricated in anodic aluminum oxide (AAO) membranes using electro-codeposition followed by long-time anneal process. The morphology, chemical composition and crystal structure were characterized by field emission scanning electron microscope (FE-SEM), high resolution transmission electron microscope (HRTEM) equipped with an energy dispersive x-ray spectrometer, and X-ray diffraction (XRD) spectroscopy. The results prove that the Fe has been successfully doped in the lattice of ZnO nanowire arrays and the estimated Fe atomic ratio is around 22%. Micro-superconducting quantum interference device (SQUID) shows that the nanowire arrays exhibit room temperature (300 K) ferromagnetic and anisotropic ferromagnetic behavior which may be a consequence of the easy magnetization direction along the wire axes and magnetostatic interaction. 相似文献
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Changzhen Liu Xiuling Wu Yongqian Wang Zhengjie Zhang 《Materials Research Bulletin》2011,46(9):1414-1416
Sheet-like ZnO with regular hexagon shape and uniform diameter has been successfully synthesized through a two-step method without any metal catalyst. First, the sheet-like ZnO precursor was synthesized in a weak alkaline carbamide environment with stirring in a constant temperature water-bath by the homogeneous precipitation method, then sheet-like ZnO was obtained by calcining at 600 °C for 2 h. The structures and optical properties of sheet-like ZnO have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL) and UV-vis-NIR spectrophotometer. The results reveal that the product is highly crystalline with hexagonal wurtzite phase and has appearance of hexagon at (0 0 0 1) plane. The HRTEM images confirm that the individual sheet-like ZnO is single crystal. The PL spectrum exhibits a narrow ultraviolet emission at 397 nm and a broad visible emission centering at 502 nm. The band gap of sheet-like ZnO is about 3.15 eV. 相似文献
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Zinc oxide nanomaterials with an average particle size of 20–30 nm are readily synthesized by the reaction of zinc acetate
and oxalic acid under hydrothermal conditions. The samples are characterized by XRD, SEM, TEM, UV and photoluminescence (PL)
studies. The average crystal size of the as prepared ZnO nanopowder is determined by XRD and the values are in good agreement
with the TEM analysis. UV absorption spectra revealed the absorption at wavelength < 370 nm indicating the smaller size of
ZnO nanoparticles. The quality and purity of ZnO nanomaterial crystalline samples are confirmed by photoluminescence spectra. 相似文献
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以无水乙醇、乙二醇甲醚、乙二醇甲醚/乙醇混合溶液(1∶1)为溶剂体系,采用溶胶-凝胶法制备了ZnO透明薄膜,并利用场发射扫描电镜、X射线衍射和反射光谱仪等研究了溶剂体系对薄膜组成、结构和光学性能的影响。结果表明,3种溶剂所制备的ZnO薄膜均为六方纤锌矿型结构,具有c轴择优取向;以乙二醇单甲醚/乙醇混合溶液(1∶1)为溶剂制备的ZnO薄膜平整、致密,在可见光区域透光率达到90%左右,禁带宽度为3.25eV,具备制作薄膜太阳能电池透明导电电极材料的应用价值。 相似文献
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I. Soumahoro R. Moubah S. Colis M. Abd-lefdil A. Berrada A. Dinia 《Thin solid films》2010,518(16):4593-4596
Zn1−xFexO thin films with different Fe content were deposited on glass substrates at 450 °C by spray pyrolysis technique. The effect of doping on the structural and optical properties of ZnO films was investigated. X-ray diffraction has shown that the films are polycrystalline and textured with the c-axis of the wurtzite structure along the growth direction. Scanning electron microscopy has shown that the surface of the films are homogeneous. The magnetic measurements performed at 5 K using a SQUID magnetometer showed the co-existence of paramagnetic, antiferromagnetic and ferromagnetic contributions. 相似文献