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以多孔阳极氧化铝(AAO)为模板,采用双槽法电沉积工艺制得高度有序的Cu/Ni多层纳米线阵列。利用扫描电镜(SEM)和透射电镜(TEM)对Cu/Ni多层纳米线进行了表征,观察到纳米线表面平滑,多层结构清晰,各子层厚度均匀,直径约为 100 nm,与AAO模板孔径基本一致。由选区电子衍射(SAED)照片可知,多层纳米线中Cu层和Ni层均为单晶结构。振动样品磁强计(VSM)测试结果表明,Cu/Ni多层纳米线阵列具有明显的垂直磁各向异性,外加磁场垂直和平行于AAO模板表面时,磁滞回线的矩形比分别为 0.701 和 0.101 ,矫顽力分别为 589 Oe和 202 Oe。通过控制铝阳极氧化工艺及电沉积时间,可获得不同直径、不同子层厚度的Cu/Ni多层纳米线阵列。 相似文献
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报道一种恒电流二次氧化制备大长径比(>1000)阳极氧化铝(AAO)模板的方法,研究氧化时间和氧化电流密度分别对制备的AAO模板的表面形貌、孔径大小、厚度等的影响.结果表明,AAO模板的表面形貌及厚度n受m氧、厚化度电约流为密2度00及μ氧m、化长时径间比的为影10响0;-当13氧00化的电高流质密量度A为AO8模m板A·.c采m用-2电时化,氧学化沉1积8方h能法在制制备备出的孔A径A为O模15板0-的20孔0中成功制备了Ni纳米线阵列,分别用扫描电镜(SEM)、高分辨透射电镜(HRTEM)、X射线衍射(XRD)和X射线能量散射光谱(EDS)对其进行了表征;结果显示,制备的Ni纳米线排列整齐有序,每根Ni纳米线直径几乎相同,约150nm,长度约为180-200μm,长径比为1200-1300,与AAO模板的参数一致.研究了Ni纳米线阵列的长径比对其磁性能的影响,发现大长径比的Ni纳米线阵列具有明显的磁各向异性,而长径比约为200的Ni纳米线阵列未表现出明显的磁各向异性.本文结果表明,恒电流二次氧化方法能制备大长径比的AAO模板,并能用于制备大长径比的一维纳米材料阵列,可望在制备具有特殊光学、磁学等性能材料方面得到应用. 相似文献
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采用铝阳极氧化法制备了Al2O3-Al-体型多孔氧化铝载体,再采用电沉积技术将TiO2沉积到氧化铝多孔的纳米孔道内,制备了催化精馏专用SO42-/TiO2-Al2O3-Al型固体酸催化剂,并以乙酸乙酯合成为模型反应,考察了水封条件,电沉积电压、电沉积时间等制备工艺条件对催化剂活性的影响.实验结果表明,适宜的制备条件为水封温度为50℃,水封时间为1 h,电沉积电压为6V,电沉积时间为30 min,在此制备条件下,醋酸转化率为31.34%.采用扫描电镜(SEM),X射线衍射分析(XRD)手段对所制备催化剂进行了表征.结果表明:阳极氧化铝膜的结构为无定型结构,TiO2在载体上呈高度分散状态. 相似文献
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阳极氧化铝模板法可控制备金属纳米线和纳米管阵列的生长机制 总被引:2,自引:0,他引:2
利用阳极氧化铝模板(AAO)进行Ni的电化学沉积, 通过在溶液中引入螯合剂控制电解质的有效浓度和电沉积的过电位, 实现了Ni纳米线和纳米管阵列的可控制备. 通过分析电沉积过程中纳米线和纳米管在不同位置生长速率(侧壁(Vw)和底端(Vb))的控制因素, 我们提出了纳米线和纳米管生长的可能机制. 当电解质浓度高而还原电位更负(如-1.5 V)时, 或者当电解质浓度低而还原电位较负(如-0.5 V)时, Vw>Vb, 可以获得Ni纳米管阵列; 当电解质浓度高而还原电位较负(如-0.5 V)时, 或者当电解质浓度低而还原电位更负(如-1.5 V)时, Vw≈Vb, 可以获得Ni纳米线阵列. 这种生长机制适用于多种金属纳米管或者纳米线阵列的可控制备. 相似文献
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应用直流电沉积法在多孔氧化铝模板中制备了高度有序的CdS纳米线阵列,并由XRD、Raman、SEM、TEM和HRTEM等进行物理化学表征.结果表明,沉积在多孔氧化铝模板中的CdS呈六角结构,c轴沿孔长度方向定向生长.紫外吸收光谱研究表明,随着纳米线尺寸的减小,纳米线阵列的吸收边向短波长方向移动,荧光光谱测量显示,CdS纳米线阵列的荧光强度高于氧化铝模板,而且在可见光区的荧光特性与激发波长无关. 相似文献
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采用恒电流沉积方法, 在多孔阳极氧化铝(AAO)模板中制备出了具有单晶结构的Ni纳米线阵列. 采用扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线衍射(XRD)技术对制备的Ni纳米线阵列的形貌及结构进行了表征. 利用振动样品磁强计(VSM)对单晶Ni纳米线阵列的磁性能进行了研究. 结果表明, 单晶镍纳米线阵列的易磁化方向为纳米线轴向, 并且与多晶纳米线相比显示出了更高的矫顽力. 直径为30 nm的纳米线具有较高的矫顽力(8.236×104 A/m)和较高的剩磁比(Mr=0.94Ms). 相似文献
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Electroless Deposition of Nickel Nanowire and Nanotube Arrays as Supports for Pt-Pd Catalyst for Ethanol Electrooxidation 下载免费PDF全文
Nickel nanowire and nanotube arrays as supports for Pt-Pd catalyst were prepared by electroless deposition with anodic aluminum oxide template. Pt-Pd composite catalyst was deposited on the arrays by displacement reaction. SEM images show that the nickel nanowires have an average diameter of 100 nm and the nickel nanotubes have an average inner diameter of 200 nm. EDS scanning reveals that elemental Pt and Pd disperse uniformly on the arrays. Cyclic voltammetry study indicates that the nickel nanotube array loaded with Pt-Pd possesses a higher electrochemical activity for ethanol oxidation than the nickel nanowire array with Pt-Pd. 相似文献
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There have been few reports on Bi-Fe intermetallic compounds because Bi and Fe are immiscible in the equilibrium states and neither alloy nor intermetallic compound exists in the binary system. In this paper, we show that, by using the nanometer-scale templates based synthesis in conjunction with the electrochemical deposition, it is possible to mix in solid solution elements that are immiscible in traditional fabrication methods. The preparation of Bi-Fe intermetallic compound nanowire arrays was investigated via an electrodeposition route by using a polycarbonate (PC) membrane template. Cyclic voltammetry, potentiostatic transient, and potentiostatic stripping were used to study the formation of Bi(x)Fe(1-x) intermetallic compounds. The compositions of Bi(1-x)Fe(x) intermetallic compound nanowire arrays were sensitive to the bath compositions and the electrodeposition potentials, and the length could be easily adjusted by varying the electrodeposition time. The electrodeposited Bi(1-x)Fe(x) intermetallic compound nanowire arrays had a parallel-to-the-wire easy magnetization. Furthermore, the spin-glass such as behavior and an unusually large characteristic time, which was about 5.26 h, were found in Bi(1-x)Fe(x) intermetallic compound nanowire arrays at room temperature. 相似文献
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建立了只需一步操作即可完成在抛光洗净的金微盘阵列电极上进行多孔化处理和钯纳米粒子修饰的方法。通过对金微盘电极连续施加3个电位,分别实现金的氧化、金的还原和电沉积钯纳米粒子。利用扫描电镜和电化学方法监控制备过程,得到的结果证实了本方法的可行性和有效性。考察了溶液pH值与氧化时间对结果的影响,在磷酸盐缓冲溶液(pH7)中氧化90s,得到的修饰电极的电化学活性面积是裸电极的42倍。同时,由于整个过程不需要更换溶液,且只需开启一次仪器,大大简化了实验操作。将制备的修饰电极用于溶解氧的电催化,对溶解氧的灵敏度达到0.1mA·L/(cm2·mg),优于文献报道结果。 相似文献
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《Electrochemistry communications》2008,10(5):798-801
Highly ordered Pd nanowire arrays (NWAs) are prepared using a porous aluminum oxide template by pulse electrodeposition. The obtained Pd nanowire arrays with the diameter of 50 nm and length of 850 nm have been characterized by scanning electron microscopy, energy dispersive X-ray analysis, and high resolution transmission electron microscope. Meanwhile, the electrocatalytic activity of Pd NWAs electrodes for methanol and isopropanol oxidation in alkaline media is studied. It is found that the obtained nanostructures exhibit excellent catalytic activity for alcohol electrooxidation. The isopropanol oxidation shows the higher activity on Pd NWAs electrode than methanol in alkaline medium. 相似文献