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ZnO微晶晶面与其光催化性能的关系(英文) 总被引:1,自引:0,他引:1
以Zn(CH3COO)2H2O和NaOH为原料,采用水热法制备ZnO微晶.通过改变水热反应时间制得了2种(O001)晶面显露情况不同的六方短柱状ZnO微晶.反应5 h时,得到(0001)晶面平滑完整的晶体;10h时,(0001)晶面被腐蚀凹陷.使用X射线衍射仪、扫描电镜分析物相组成和晶体显微形貌.并测试2种ZnO微晶的紫外光催化降解亚甲基蓝性能.结果直接证明:(0001)晶面对ZnO六方短柱状微晶光催化活性的高低起决定性作用,当(0001)晶面被溶蚀时,ZnO微晶无光催化降解性. 相似文献
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采用两步电化学法分别在氧化铟锡(indium-tin oxide,ITO)玻璃基板和经缓冲层处理的ITO玻璃基板上制备ZnO微米管和纳米管。从Zn(NO3)2和六亚甲基四胺水溶液中阴极电沉积制备ZnO柱状晶体。用乙二胺水溶液进行电化学腐蚀。用X射线衍射仪和扫描电镜研究产物的物相和形貌演变,初步探索管状结构的形成机理,结果表明:管状结构由柱状结构中心腐蚀而形成,由柱状演变为喇叭状,再到管状;腐蚀首先发生在亚稳态的(0001)面,主要沿c轴方向进行;同时,从缺陷浓度高的中心向缺陷浓度低的外围进行。退火实验验证了缺陷腐蚀机理。 相似文献
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ZnO纳米片生长过程的研究 总被引:2,自引:1,他引:1
本文研究了以碱式硫酸锌为前驱体,三聚磷酸钠为表面改性介质,水热法获得ZnO片状结构的形成机理以及工艺参数对ZnO晶体形貌的影响,运用场发射扫描电镜、透射电镜等手段对所得ZnO粉末进行表征,结果表明:磷酸根可以修饰ZnO晶体的生长形貌,限制沿c轴方向的快速生长,而向二维空间发展形成片状结构.改变三聚磷酸钠的浓度和水热溶液pH值,所得ZnO晶体的形貌发生变化,当三聚磷酸钠的浓度为0.1 mol/L,pH值为9~10时,180℃水热28 h可获得厚度小于50nm0的六角形片状ZnO晶体. 相似文献
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Nanosized ZnO with prismatic form was prepared using homogeneous precipitation process and its electrochemical performance was investigated by the measurements of electrochemical cycle behaviors and passivation polarization curves. The discharge capacity delivered by nanosized ZnO still achieved about 600 mAh/g until the 250th cycle. Nanosized ZnO exhibited higher midpoint discharge voltage, better cycle stability and passivation toleration than commercial ZnO. Furthermore, nanosized ZnO showed the morphology evolution process differed slightly from that of the commercial ZnO, including morphology maintenance, orientation growth and the formation of Zn dendrites. The epitaxial growth, texture growth and crystal growth habit were put forward to illuminate the morphology evolution process. 相似文献
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Xinchang Wang Minggang Zhao Fang Liu Jianfeng Jia Xinjian Li Liangliang Cao 《Ceramics International》2013
Pure and Ni-doped ZnO nanofibers were synthesized using the electrospinning method. The morphology, crystal structure and optical properties of the nanofibers were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and photoluminescence (PL) spectroscopy, respectively. It is found that Ni doping does not change the morphology and crystal structures of the nanofibers, and the ultraviolet emissions of ZnO nanofibers present red shift with increasing Ni doping concentration. C2H2 sensing properties of the sensors based on the nanofibers were investigated. The results show that the C2H2 sensing properties of ZnO nanofibers are effectively improved by Ni doping, and 5 at% Ni-doped ZnO nanofibers exhibit a maximum sensitivity to C2H2 gas. 相似文献
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分别采用水热和沉淀法制备ZnO光催化剂,利用X射线粉末衍射(XRD)和扫描电镜(SEM)对其物相和外貌进行分析观测.了解表征手段所反映的材料的物质结构信息。通过降解亚甲基蓝实验比较不同制备条件下所得ZnO的光催化性能。了解催化剂制备方法对其晶相、形貌及催化性能的影响。 相似文献
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Ming Fu Shulei Li Jia Yao Hongpeng Wu Dawei He Yongsheng Wang 《Journal of Porous Materials》2013,20(6):1485-1489
Ag-doped ZnO inverse opal structures were prepared by electrochemical deposition using polystyrene colloidal crystal templates. The Ag-doped ZnO structures had granular morphology, but this morphology became smooth using a three-dimensional (3D) porous template in the same electrolyte. The Ag-doped ZnO structures were characterized using energy-dispersive X-ray spectroscopy, and the lattice parameter was found to increase compared with undoped ZnO as verified by X-ray diffraction. Strong reflection photonic stop bands centered at 495 and 681 nm were detected from inverse opals templated from microspheres having diameters of 285 and 370 nm. The filling ratio of Ag-doped ZnO inverse opals using the template was lower than that of the uniform film growth of undoped ZnO. Moreover, photochemical cell analysis revealed that doped ZnO inverse opals with n- and p-type conductivities were successfully formed using electrolytes with different silver ion concentrations. 相似文献
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ZnO colloid crystals were coated on quartz crystal microbalance (QCM) by the self-assembly method. Field emission scanning electron microscopy and X-ray diffraction were used to analyze the morphology and crystal structure of ZnO colloid crystals. The sensing behavior was examined by measuring the resonance frequency shifts of QCM. The device exhibits excellent humidity sensing properties in the whole humidity range from 11% to 95%, such as good linearity, fast response time and recovery time, excellent reliability, and long-term stability. We also discussed the adsorption and desorption of water molecules on ZnO colloid crystals at different humidity conditions. 相似文献
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Jin Young Park Hong Chae Jung G. Seeta Rama Raju Byung Kee Moon Jung Hyun Jeong Hae Young Choi Jung Hwan Kim 《Ceramics International》2013
ZnO nanoparticles (NPs) with rod, bullet and broom-like morphologies have been synthesized by the solvothermal method. Structural analysis revealed ZnO NPs to be of the single crystal wrutzite hexagonal structure. Their size and morphology were controlled by varying the polarity of solvents. The aspect ratio of ZnO NPs at the lower polarity was below 2, and their shape was like a bullet. When increasing the polarity of solvent, the aspect ratio also increases and the shape changes to a rod-like morphology. This process is very simple and scalable. In addition, it can be used for fundamental studies of the tunable morphology formation. 相似文献
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采用硅烷偶联剂KH-550修饰纳米ZnO,制备了MC尼龙6/纳米ZnO复合材料。力学性能测试表明,当纳米ZnO质量分数为1%时复合材料的力学性能最优,拉伸强度比纯MC尼龙6提高25.6%,断裂伸长率提高165.6%,简支梁冲击强度提高70.1%,这说明纳米ZnO可起到同时增强增韧的作用。扫描电子显微镜分析表明,纳米ZnO质量分数为1%时,纳米ZnO在MC尼龙6基体中分散最好,达到了纳米级分散;由X衍射分析发现,纳米ZnO没有改变MC尼龙6的结晶形态,纳米ZnO质量分数为1%时复合材料的结晶形态结构优越。 相似文献
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H. Wang Z. P. Zhang X. N. Wang Q. Mo Y. Wang J. H. Zhu H. B. Wang F. J. Yang Y. Jiang 《Nanoscale research letters》2008,3(9):309-314
By thermal evaporation of pure ZnO powders, high-density vertical-aligned ZnO nanorod arrays with diameter ranged in 80–250 nm
were successfully synthesized on Si substrates covered with ZnO seed layers. It was revealed that the morphology, orientation,
crystal, and optical quality of the ZnO nanorod arrays highly depend on the crystal quality of ZnO seed layers, which was
confirmed by the characterizations of field-emission scanning electron microscopy, X-ray diffraction, transmission electron
microscopy, and photoluminescence measurements. For ZnO seed layer with wurtzite structure, the ZnO nanorods grew exactly
normal to the substrate with perfect wurtzite structure, strong near-band-edge emission, and neglectable deep-level emission.
The nanorods synthesized on the polycrystalline ZnO seed layer presented random orientation, wide diameter, and weak deep-level
emission. This article provides a C-free and Au-free method for large-scale synthesis of vertical-aligned ZnO nanorod arrays
by controlling the crystal quality of the seed layer. 相似文献