磁性金属纳米结构的制备与表征

采用电化学沉积方法成功地制备了高度有序的镍纳米管/线阵列结构,并用扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线衍射(XRD)对产物的微观形貌和化学结构进行了表征和分析.测试结果显示,镍纳米结构阵列规整,镍纳米管壁具有多晶体结构;X射线衍射图谱表明,镍纳米管壁具有较高的结晶度.研究了沉积时间对镍纳米结构的影响.     

电沉积法制备镍纳米管阵列及磁性研究

利用电沉积法在多孔阳极氧化铝模板中组装了镍纳米管阵列,分别利用SEM、TEM、XRD和VSM对镍纳米管的形貌、结构和磁性能进行表征。结果表明,所制备的镍纳米管阵列,属面心立方(fcc)结构,磁滞回线表明制备的镍纳米管阵列具有磁单轴各向异性和单磁畴特性。     

低温水热合成钛酸钡纳米管阵列薄膜及性能研究

以二氧化钛纳米管阵列为模版,用水热法合成了钛酸钡纳米管阵列薄膜.讨论了水热温度、水热时间、碱的浓度对其生长形貌的影响.用X射线衍射仪、扫描电子显微镜表征了其晶体结构及微观形貌;用热重-差示扫描量热仪测定了材料的热学性能;用宽频介电阻抗谱仪测试了样品的介电性能.结果表明,在低至100℃水热温度下反应6h即可制得单一相的钛...     

不同结构镍纳米线阵列的制备及其磁性

采用直流电沉积在多孔有序氧化铝模板中制备了不同结构的有序镍纳米线阵列。采用扫描电子显微镜和透射电子显微镜对所制备的镍纳米线的形貌和结构进行了表征。研究了镍纳米线不同结构对镍纳米线阵列磁性性能的影响规律。当电沉积电压为2.5V时制备的镍纳米线为多晶结构;电沉积电压4V时,镍纳米线为沿[220]择优取向的单晶结构;电沉积电压大于5V时,择优取向由[220]转为[111]方向。磁滞回线结果表明,单晶镍纳米线阵列与多晶纳米线阵列相比具有更高的矩形度,沿[111]择优取向的单晶纳米线相比沿[220]取向的单晶镍纳米线具有更大的矩形度,表现出显著的磁各向异性。     

模板法制备DyCoxZnyOz纳米管阵列及磁性研究

采用减压抽滤法在多孔阳极氧化铝模板（AAM）纳米孔道中构筑DyCo_xZn_yO_z纳米管阵列,采用扫描电镜（SEM）和透射电镜（TEM）观察DyCo_xZn_yO_z纳米管阵列和单根纳米管形貌,用选区电子衍射（SAED）、X-射线衍射（XRD）及能量色散谱（EDS）表征纳米管的结构和元素组成,结果表明,DyCoxZnyOz纳米管为非晶态结构,纳米管元素组成的原子百分比Dy：Co：Zn：O为4.86：1.67：1.70：91.77,质量百分比Dy：Co：Zn：O为32：4.42：4.07：59.51。以振动样品磁强计（VSM）研究了DyCo_xZn_yO_z纳米管阵列磁性能,实验结果表明,DyCo_xZn_yO_z纳米管阵列易磁化方向为垂直于纳米管阵列方向,磁各向异性源于形状各向异性,DyCo_xZn_yO_z纳米管阵列具备软磁体特征。     

多孔模板法制备热塑性聚氨酯(TPU)纳米管

采用聚合物溶液和熔体浸润多孔阳极氧化铝（AAO）模板的物理方法，成功制备了通孔的热塑性聚氨酯（TPU）纳米管及其阵列结构．扫描电子显微镜（SEM）和透射电子显微镜（1EM）测试表明：有效地调整溶液滴加量可制备出不同结构的聚合物纳米管阵列．以浓度为7．0％（wt）TPU溶液为例，研究了溶液滴加量对纳米管结构之间的关系，2μL为制得TPU纳米管阵列结构的最佳滴加量．并探索首次浸润程度对纳米管结构的影响，完善了模板浸润法的多次浸润机理．     

载Pt-TiO2纳米管阵列制备及其光电催化性能

采用阳极氧化法在纯钛箔表面制备TiO2纳米管,再用直流电沉积法在纳米管内沉积Pt,制备出载Pt-TiO2纳米管电极.并采用场发射扫描电子显微镜(FESEM)、X射线衍射(XRD)对其进行表征.研究载Pt-TiO2纳米管阵列与TiO2纳米管阵列对有机磷农药敌敌畏(DDVP)的光电催化降解效果,并与光催化、电降解做了简单对比.结果表明:所制Pt-TiO2纳米管存在锐钛矿晶型TiO2,其饱合光电流比TiO2纳米管大.与单独光催化、电降解相比,载Pt-TiO2纳米管电极光电催化降解效果更显著.     

模板浸润法制备聚合物纳米管阵列

以孔径为200nm的多孔氧化铝膜（AAO）为模板、常规分子量的通用聚合物为原料，采用聚合物溶液或熔体浸润模板纳米孔的物理技术，进行了多种聚合物纳米管的制备研究。结果表明：聚苯乙烯、尼龙66、聚丙烯、ABS、热塑性聚氨酯等多种聚合物纳米管及其纳米管阵列成功制得。运用扫描电子显微镜（SEM）和透射电子显微镜（TEM）观察了纳米管的微观形貌和阵列结构。并探讨了聚合物性质、纳米管制备工艺与纳米管结构的关系，初步探索了多孔模板法制备聚合物纳米管的机理。     

溶胶-凝胶模板法制备K_(0.5)Na_(0.5)NbO_3纳米管阵列及其表征

以乙醇铌、乙酸钾和乙酸钠为原料,乙二醇甲醚为溶剂,采用溶胶-凝胶(Sol-Gel)阳极氧化铝(AAO)模板法制备了K0.5Na0.5NbO3(KNN)纳米管阵列.利用热分析确定晶化温度,采用X射线衍射、扫描电子显微镜和透射电子显微镜表征KNN纳米管的物相、形貌和微观结构.结果表明,KNN最佳的晶化温度为700℃;KNN纳米管阵列结晶性良好,为单斜钙钛矿多晶结构,单根纳米管的外径约为200nm,管壁厚约为20nm.对KNN纳米管阵列的铁电性能表征显示,其剩余极化率Pr约为1.86μC/cm2,矫顽场Ec约为0.68kV/cm。     

钴铁氧体纳米管阵列制备及其磁学性能(英文)

为了研究一维钴铁氧体纳米管阵列的磁学性质,应用氧化铝模板具有的约束作用和毛细管作用,结合溶胶凝胶技术合成了钴铁氧体纳米管阵列.在140℃条件下,通过包含Fe(AO)3和Co(AO)2(物质的量之比为2∶1)的柠檬酸和乙二醇混合溶液(物质的量之比为1∶4)酯化反应得到溶胶.将氧化铝模板浸入溶胶几次后取出,取出充满溶胶的氧化铝模板,在大气气氛中,以0.6℃/min～5℃/min的升温速度将样品由室温升温至500℃,保温8 h.结果表明,在控制Fe3+离子浓度的条件下也可以合成钴铁氧体纳米线(Fe3+离子浓度大于1 mol/L)和"竹节"型纳米管(Fe3+离子浓度介于0.5 mol/L～1.0 mol/L),但重点进行了其纳米管阵列(Fe3+离子浓度小于0.5 mol/L)合成和磁学性能测试.透射电子显微镜(TEM)、高分辨电镜(HRTEM)的观察以及粉末X光衍射(XRD)测试结果表明纳米管组成为多晶结构.纳米管的直径取决于氧化铝模板的孔径,大约为200 nm,其长度约几个微米.应用样品振动磁强计对样品磁性进行了表征,结果表明纳米管阵列未表现出方向特性,矫顽力随着升温速率的降低而升高,在0.6℃/min的升温速率时,矫顽力达到最高的1 445 kOe,简单讨论了其形成原因.     

Template-based synthesis and magnetic properties of Ni nanotube arrays with different diameters

Ni nanotube arrays with different diameters were fabricated in the pores of the porous anodic alumina membranes by direct current electrodeposition. The crystal structure and micrograph of Ni nanotube arrays were characterized by X-ray diffraction, transmission electron microscopy, and field-emission scanning electron microscopy. The results indicate that Ni nanotubes have no preferred orientation and are polycrystalline structure. The magnetic behaviors of Ni nanotube arrays with different diameters are investigated, and the coercivity of Ni nanotubes depends strongly on their diameters. The size-dependent behavior of the coercivity is qualitatively explained in terms of localized magnetization reversal.     

Ni纳米管的电化学模板法制备及表征

本文采用一种简单而有效的电化学方法在硫酸铵体系中利用氧化铝模板(AAO)成功制备出规则有序的Ni的管状纳米阵列.使用这种方法可获得外径约为70nm,内径约为50nm的Ni纳米管.对所得的Ni纳米管进行了扫描电镜(SEM)、透射电镜(TEM)、选区电子衍射图(SAED)和X射线衍射(XRD)分析,结果表明:该方法制备的Ni纳米管高度有序,大小均一,其形貌受控于氧化铝模板的结构,外径与模板的孔径相等.     

Synthesis of ZnO nanotube arrays and heterostructures of Cu-ZnO coaxial nanotubes by electrodeposition-oxidation method

Semiconductor ZnO nanotube arrays and heterostructures of Cu-ZnO coaxial nanotubes have been synthesized by electrodeposition into porous anodic alumina membranes and subsequent oxidation. Scanning electron microscopy and transmission electron microscopy indicate that the ZnO nanotubular arrays and Cu-ZnO coaxial nanotubular arrays are of large-area and highly ordered. X-ray diffraction patterns show that the nanotubes are polycrystalline. Photoluminescence spectra of the Cu-ZnO nanotubes show that a violet peak, a blue peak and a green peak are centered at 422 nm, 480 nm and 537 nm, respectively. The ordered ZnO nanotube arrays and heterostructures of Cu-ZnO coaxial nanotubes may have promising potential applications in nanodevices.     

A template-based electrochemical method for the synthesis of high dense nickel nanotube arrays

High dense Ni nanotube arrays have been successfully fabricated using electrochemical method with the assistance of anodic aluminum oxide (AAO) template from NiSO4 aqueous solution without any additive. Field emission scanning electron microscope (FE-SEM) results indicate that the pores of AAO template are high uniform and all the pores are filled with Ni nanotubes. Transmission electron microscope (TEM) results demonstrate that the diameter of Ni nanotubes is about 65 nm. The electron diffraction (ED) pattern results show that the Ni nanotubes are polycrystalline. X-ray diffraction (XRD) pattern shows that the electrodeposited nickel is hexagonal crystal structure.     

Efficient growth of aligned SnO2 nanorod arrays on hematite (α-Fe2O3) nanotube arrays for photoelectrochemical and photocatalytic applications

SnO₂ nanorod arrays were fabricated on hematiete nanotube arrays by an efficient hydrothermal method. The hematiete nanotube arrays were prepared by anodization of pure iron foil in an ethylene glycol solution. SnO₂ nanorod arrays grew from the bottom of hematite nanotubes and were firmly combined with the iron foil substrate. The morphology and microstructure of SnO₂ nanorod arrays are investigated by field-emission scanning electron microscopy, grazing incidence X-ray diffraction and UV–Vis absorbance spectra. The sample presented typical SnO₂ nanorod arrays (reacted for 2 h) generally of 400 nm in length and 50 nm in side width showed the best photocatalytic activity and photoelectrochemical response under the UV illumination. It should be attributed to the effective electron–hole separation and the excellent electron transfer pathway along the 1D SnO₂ nanorod arrays and hematiete nanotube arrays.     

One-step fabrication of ordered Pt-Cu alloy nanotube arrays for ethanol electrooxidation

Novel one dimensional (1D) nanostructured metallic electrodes have received much attention in the area of the fuel cell because of their extremely high surface-to-volume ratios and excellent activities. Here, we report the one-step fabrication of Pt-Cu alloy nanotube arrays. As determined by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, ordered Pt-Cu alloy nanotubes have been successfully fabricated utilizing a nanochannel alumina template. The electrocatalytic activities of the Pt-Cu alloy nanotubes for the oxidation of ethanol in acidic medium were investigated by cyclic voltammetry. The results show that the Pt-Cu alloy nanotubes can be used as effective electrocatalysts for ethanol oxidation in direct alcohol fuel cells.     

酚醛树脂原位催化裂解制备低维碳纳米结构

以Ni（NO₃）₂·6H₂O为催化剂前躯体,原位催化裂解酚醛树脂制备了碳洋葱、竹节碳和碳纳米管等低维碳纳米结构;用粉体X-射线衍射（XRD）、扫描电镜（SEM）和透射电镜（TEM）等手段对低维碳纳米结构进行了表征。结果表明;当Ni（NO₃）₂·6H₂O与苯酚物质量比小于0.01时,Ni催化剂易分散,碳纳米管易生成,管径均一、分布稠密;当Ni（NO₃）₂·6H₂O与苯酚物质量比大于0.04时,Ni催化剂易团聚,碳纳米管管径分布较宽,分布稀疏;当Ni（NO₃）₂·6H₂O与苯酚物质量比为0.10时,Ni催化剂团聚现象严重,难以生成碳纳米管;提出了碳洋葱、竹节碳和碳纳米管不同碳纳米结构可能的形成机理。     

Synthesis of ordered ZnS nanotubes by MOCVD-template method

Semiconductor ZnS nanotubes arrays were synthesized in the pores of the porous anodic alumina (PAA) membranes by using metal organic chemical vapor deposition (MOCVD) template methods. The morphology and structure of the ZnS nanotubes were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED) and X-ray diffraction (XRD). It is found that the ZnS nanotubes with diameters in range of 140–250 nm and the length up to tens of microns are polycrystalline. Energy-dispersion spectroscopy (EDS) and X-ray photoelectron spectroscopy analysis (XPS) indicate that the stoichiometric ZnS was formed. A green-blue emission band centered at 510 nm was observed in the photoluminescence spectrum of the ZnS nanotubes.