氧化钕纳米线的制备与表征

以硝酸钕和尿素为主要原料,多孔阳极氧化铝膜(AAO)为模板,分别采用普通浸渗和压力浸渗法制备了氧化钕纳米线.采用扫描电子显微镜(SEM)、透射电子显微镜(TEM),X射线衍射仪(XRD)和能量仪(EDS)对纳米线的形貌,结构及组成进行了表征.结果表明:两种浸渗方法均可得到氧化钕纳米线,压力溶胶浸渗有利于模板纳米孔填充度的提高,可以得到高长径比的氧化钕纳米线.     

模板法电沉积钆钴合金纳米线阵列

在草酸电解液中用二次阳极氧化法制备多孔阳极化氧化铝(Anodic Aluminum Oxide,AAO)模板。通过对电流密度、氧化时间、电解液浓度等参数的调整,最终获得孔洞分布均匀、孔径基本一致、孔口呈六边形的AAO模板。采用不去除中间铝,用逐级降压法和电化学法减薄阻挡层,然后利用中间铝作为电极,在非水体系中以AAO为模板,直流电沉积钆钴合金纳米线阵列。经过SEM观测,AAO模板孔径在60nm左右,去阻挡层前后变化不大,制备的钆钴合金纳米线排列有序、尺寸一致;EDS测定表明纳米线为钆钴合金及少量氧化物纳米线,钆钴摩尔质量比为1:7.5,钆钴合金质量分数为90.66%;XRD分析图谱表明所得到的钆钴合金纳米线为非晶态。     

锆钛酸铅纳米管制备工艺研究

研究了溶胶-凝胶浸渍阳极氧化三氧化二铝（AAO）模板法制备Pb(Zr0.52Ti0.48)O3（PZT）一维纳米结构的工艺方法。试验结果表明,以硝酸氧锆、醋酸铅、钛酸丁酯（按0.52:1:0.48的摩尔配比）为原料,以乙二醇为溶剂,可获得稳定的PZT溶胶,通过反复滴加浸渍氧化铝模板,最终经650 ℃晶化处理和腐蚀AAO后得到PZT纳米管。样品表征结果说明,制得的PZT纳米管为钙钛矿相,表面结构完整、孔径均一、排列均匀整齐,长50 μm、管径300 nm、壁厚40 nm。     

非水体系中电沉积稀土永磁功能合金纳米线

利用多孔阳极氧化铝模板，在尿素-NaBr-KBr-酰胺体系中电沉积稀土-铁系金属（La-Co）合金纳米线。用扫描电子显微镜（SEM）观察（La-Co）合金纳米线的表面形貌，用磁振动样品磁强计（VSM）研究了LaCo合金的磁性。结果表明，纳米线直径较为均匀，且每条纳米线的尺寸为70～80nm，与AAO模板的纳米孔径大小相符合：X射线衍射（XRD）分析表明，La-Co合金为LaCo5晶体;在室温下呈现顺磁性的La，当与Co形成合金后，饱和磁矩接近于磁性金属Co。     

Fe磁性纳米线阵列的制备与微波吸收性能研究

采用脉冲和直流电沉积方式，以FeSO4，（NH4）2SO4等混合溶液为电解液，在多孔阳极氧化铝模板（AAO模板）微孔内成功制备出Fe磁性纳米线阵列。用X射线衍射仪、扫描电镜及HP8510B网络分析仪对多孔AAO模板以及Fe磁性纳米线阵列的微观形貌、组织结构及微波吸收性能进行了测试。结果表明，沉积的纳米线为立方结构α=Fe，且纳米线阵列存在（110）择优取向性。Fe纳米线组装后的铝基AAO模板吸波材料具有良好的微波吸收效果，在2GHz～18GHz频段内的最大反射率为-4．8dB，大于-1dB的吸收带宽约为10GHz。     

Bi_(3.15)Nd_(0.85)Ti_3O_(12)纳米管阵列的制备与微结构表征

采用溶胶凝胶法,在孔径为200 nm的阳极氧化铝模板中制备了Bi_3.15Nd_0.85Ti_3O_(12)纳米管阵列.通过XRD、SEM、TEM、HRTEM、SAED和Raman光谱测试手段对纳米管阵列的物相、微结构和声子振动特性进行了表征.研究表明,所合成BNdT纳米管为钙钛矿相多晶结构,纳米管外径约为200 nm,管壁厚约10 nm,管径和长度与所用AAO模板尺寸一致.Raman光谱分析表明,Nd离子取代了类钙钛矿层中A位的Bi离子.     

氧化铝模板的制备方法及特征

介绍了用二次阳极氧化法制备氧化铝模板的步骤，并对氧化铝模板及随后制备的纳米线进行了观察。结果表明，所制的氧化铝模板有序性较好，可以用来制备纳米线。     

多孔阳极氧化铝膜的制备及应用研究

详细研究了合成条件对制备多孔阳极氧化铝膜的影响,以所制备的多孔阳极氧化铝膜为模板,初步研究了氧化铁纳米线的制备。实验1.带基体的多孔AAO模板的制备。铝片预处理。实验铝片纯度为99.99%,厚度0.3mm。将铝片依次在丙酮、乙醇和蒸馏水中超声清洗去除表面的油污。然后     

阳极氧化铝样模法制备纳米线阵列的发展趋势

在具有纳米孔洞的阳极氧化铝(AAO)模板上，电沉积金属和半导体微粒，可制备出高度有序的一维金属半导体纳米线阵列。样模法制备纳米材料是国内外竞相研究的热点，阳极氧化铝膜以其良好的高密度纳米孔径正逐渐引起人们的关注。     

采用溶胶-凝胶法在多孔氧化铝模板上制备立方相WO3纳米线

采用溶胶-凝胶法在纳米孔氧化铝模板上成功制备形貌各异的WO3纳米线.X射线衍射分析表明所制备的WO3纳米线为立方相结构.经扫描电子显微镜观察发现产物多数为菊花状WO3纳米线,其直径约10～80 nm,长约几微米.与空气气氛相比,氩气气氛更有助于WCl6三嵌段共聚物溶胶在多孔氧化铝模板上形成形貌各异的WO3纳米线.     

Preparation and characterization of La-Co alloy nanowire arrays by electrodeposition in AAO template under nonaqueous system

La-Co alloy nanowires can be made in pulse reversal current（PRC） and direct current（DC） electrodepositions under nonaqueous system, with the porous anodic aluminum oxide（AAO） as template. This membrane is subject to the dual-oxidation （two-step） anodizing. Scanning electron microscope（SEM） examination shows that all of the nanowires have uniform diameter about 200 nm, and their diameters are determined by the pore diameter of applied AAO template. X-ray energy dispersion analysis indicates that the chemical composition of La and Co elements is very close to 1：2 in stoichiometry. X-ray diffraction pattern investigation demonstrates that La-Co nanowire is the face-centered cubic（FCC） LaCo13.     

Fabrication of Pd-Fe nanowires with a high aspect ratio by AAO template-assisted electrodeposition

In this study, vertically oriented Pd_0.86Fe_0.14 nanowires have been fabricated using an anodized aluminum oxide (AAO) template by direct voltage electrodeposition at room temperature. AAO template-assisted electrodeposition of Pd-Fe was carried out in Pd(NH₃)₂Cl₂:FeSO₄·7H₂O solution. The AAO template and the Pd_0.86Fe_0.14 nanowires were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) methods and X-ray diffraction (XRD). It was observed that the Pd_0.86Fe_0.14 nanowires were approximately 65 nm in diameter and 10 μm in length with an aspect ratio of 153 in a relatively large area of about 4 cm². The nucleation rate and the number of atoms in the critical nucleus are determined from the analysis of current transients.     

Self-Ordered Nanoporous Alumina Templates Formed by Anodization of Aluminum in Oxalic Acid

Anodic aluminum oxide (AAO) membranes with highly ordered nanopores serve as ideal templates for the formation of various nanostructured materials. The procedure of the template preparation is based on a two-step self-organized anodization of aluminum. In the current study, AAO templates were fabricated in 0.3?M oxalic acid under the anodizing potential range of 30?C60?V at an electrolyte temperature of ~5°C. The AAO templates were analyzed using scanning electron microscopy, x-ray diffraction, Fourier-transform infrared spectroscopy, and differential thermal analysis. The as obtained layers are amorphous; the mean pore size is between 40?nm and 75?nm and increases with the increase of the anodization potential. Well-defined pores across the whole aluminum template, a pore density of ~10¹⁰?pores/cm², and a tendency to form a porous structure with hexagonal symmetry were observed.     

Zn0.95Co0.05O纳米线和纳米管的电泳沉积法可控合成（英文）

以阳极氧化铝为模板通过电泳沉积法制备Zn0.95Co0.05O纳米线和纳米管,并对电泳沉积法制备纳米线(管)的机理进行研究。系统的结构表征表明所得的纳米管和纳米线是由8～15nm的纤锌矿纳米晶构成的多晶结构,Co2+离子以代位掺杂形式掺入晶格,取代了晶格中的Zn2+离子。磁性表征显示制备的纳米线和纳米管具有室温铁磁性。由于Co在纳米线(管)中表面择优分布,纳米管的磁性明显高于纳米线。     

Controlled synthesis of highly ordered CuO nanowire arrays by template-based sol-gel route

The highly ordered CuO nanowire arrays of composite-oxides were synthesized within a porous anodic aluminum oxide（AAO） template by a citrate-based sol-gel route. A vacuum system was applied to draw the gel into the template pores, which conquers the only driving force of this technique-capillary action, then the gel was thermally treated to prepare desired CuO nanowires. The results of scanning electron microscopy（SEM） indicate that the CuO nanowires are very uniformly assembled and parallel to each other in the pores of the anodic aluminum oxide（AAO） template membranes. The results of X-ray diffraction（XRD） and the selected-area electron diffraction（SAED） indicate that the CuO nanowires are monoclinic-type crystalline structure. Furthermore, X-ray photoelectron spectroscopy （XPS） demonstrates that the stoichiometric CuO is formed.     

Unique nanostructures in NiCo alloy nanowires

NiCo alloy nanowires have been fabricated by electrodeposition using an anodized aluminum oxide (AAO) template. Single-crystalline and polycrystalline alloy nanowires have been obtained, and their microstructure was strongly dependent on the deposition conditions (current density and composition). In addition, unique nanostructures have been observed in NiCo alloy nanowires. Bamboo or layer structures were found for 15 and 25 at.% Co, respectively. The investigation of the mechanisms shows that these particular structures are related to the different diffusion rates of Ni and Co on the surface of the AAO template. The work demonstrates that as well as single-crystalline and polycrystalline nanowires, other unique nanostructures (layered and bamboo in this work) can be achieved through careful control of the preparation conditions.     

Formation of oxide nanotubes via oxidation of Fe,Cu and Ni nanowires and their structural stability: Difference in formation and shrinkage behavior of interior pores

Changes in the morphology of Fe, Cu and Ni nanowires with a diameter of 55 nm during oxidation at 423–923 K were studied by transmission electron microscopy. Oxide nanotubes with a cylindrical interior pore of uniform diameter were formed after the oxidation of Fe and Cu nanowires in air at 573 and 423 K, respectively, while the Ni nanowires became bamboo-like nanowires of NiO with separate interior voids after oxidation at 673–773 K. Oxide nanotubes of Fe and Cu and the bamboo structures of NiO showed a tendency to shrink into solid oxide nanowires after annealing at higher temperatures in air. In the shrinking process of Fe₃O₄ nanotubes, however, an array of additional nanovoids was observed along the inner wall of the nanotubes, suggesting the formation of a duplex porous nanostructure. This can be explained by the recombination of vacancies diffusing outward from the inner cylindrical pore.     

Synthesis of anodic aluminum oxide (AAO) at relatively high temperatures. Study of the influence of anodization conditions on the alumina structural features

Anodic aluminum oxide (AAO) is a well known template for nanofabrication. Structural features of AAO like pore diameter, interpore distance, porosity, pore density can be fully controlled by operating conditions of anodization. Typically, self-organized two-step anodization is carried out at low temperature (below room temperature) and is a time consuming process. There are individual experiments describing anodization at temperatures close to room temperature. In our study, furthermore, a systematic analysis of the anodization condition influence on the nanoporous alumina structural features was done. The anodization temperature was ranging from 35 to 50 °C increasing significantly current density of the processes, which has increased oxide film growth rate. The anodizing potential ranged from 20 to 60 V and time of the anodization steps was 30, 60 or 120 min. The data obtained has shown that the pore diameter increases with potential, temperature and time of anodization, while the interpore distance is influenced solely by the potential. Temperature and time changes do not affect the interpore distance. Porosity is also influenced by potential, temperature and duration of anodization. Pore density is influenced only by the potential. The synthesis of AAO reported here gives possibilities to obtain the AAO templates in a faster and cheaper way, essential for researchers applying anodic alumina as a template.