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1.
铁纳米线阵列的制备及磁性研究   总被引:1,自引:0,他引:1  
采用二次阳极氧化法制备高度有序的多孔氧化铝模板,以高度有序的阳极氧化铝为模板,用交流电沉积的方法以较低的电压在孔洞中组装了铁纳米线有序阵列.采用场发射扫描电镜(FESEM)对模板和纳米线的形貌和结构进行了表征,采用物理特性测量系统(PMMA)测量了铁纳米线的磁滞回线,结果表明纳米线是均匀连续的,直径为50 nm左右,纳米线在平行于纳米线轴的方向的矫顽力为2 259 Oe,矩形比为0.92,铁纳米线阵列有高的磁各向异性,适用于垂直磁记录介质.  相似文献   

2.
撞击流反应-沉淀法制纳米铜粉   总被引:10,自引:0,他引:10  
采用液相还原-沉淀法在浸没循环撞击流反应器中,以氨水作为络合剂,聚乙烯吡咯烷酮(PVP)为分散剂,用硼氢化钾(KBH4)还原氯化铜制得纳米铜粉,通过单因素法初步得到影响粒径大小各因素的最佳工艺条件,XRD检测表明在优化条件下制得的产物主要是单质铜,TEM检测结果表明铜粉粒径为5~20nm。  相似文献   

3.
采用两步氧化法制备出双面多孔阳极氧化铝模板(AAO),并进一步发展了模板通孔工艺,得到单层高密度多孔氧化铝模板,并用XRD、SEM和AFM对模板结构进行了表征.结果表明,草酸环境下制备的AAO模板孔排列高度规整,孔密度为10^11个/cm^2量级,孔径为45~55nm,孔间距为100~120nm.  相似文献   

4.
PEDOT nanotubes were prepared by a template synthesis method. Based on our template, it was deduced that there are two successive processes in the formation of nanotubes. The first step is soakage of the porous templates by a polymer solution, and the second step is adsorption of free charged cationic groups and doped PEDOT onto the template surface with negative charges. XRD results showed that well orientated PEDOT chains were formed during the synthesis, moreover the arrange conductivity of molecular chains strongly affect the structures of PEDOT nanotubes. The nanotubes were measured to be about 5.5–17.6 S/cm, which is higher than that of nanotube pellet due to the high contact resistance between the adjacent nanotubes. Funded National Natural Science Foundation of China(No.: 60372002)  相似文献   

5.
以CuSO4·5H2O和次亚磷酸钠(NaH2PO2)为原料,采用控制反应温度的方法实现了均相体系内铜纳米粒子的还原制备,通过X射线衍射分析(XRD)、扫描电子显微镜(SEM)对产物物相和形貌进行了表征,实验结果表明,反应体系在70℃下反应20min可以得到的产物为粒径分布在70nm~150nm的球形铜纳米粒子。  相似文献   

6.
Highly ordered nickel monoxide (NiO) nanowire arrays were fabricated by sol-gel synthesis within the pores of anodic alumina membrane (AAM). Scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) were used to characterize the topography and crystalloid structure of NiO nanowire arrays. The length and diameter of the NiO nanowires depended on the thickness of the AAM and the diameter of the pores. The results indicated that the NiO nanowires were uniformly assembled into the ordered nanopores of the AAM and paralleled to each other. Nickel monoxide nanotubes were also fabricated with the same method by changing the immersing time. This new method to prepare NiO nanowire arrays may be important from gas sensors to various engineering materials.  相似文献   

7.
CdS nanowire arrays were synthesized by altering current(AC) electrodeposition in the porous anodic alumina film prepared by aluminium anodizing in oxalic acid. These nanowires have a uniform diameter of about 45 nm corresponding to the pore size of the films used and length up to several microns. The X-ray diffraction(XRD) pattern indicates that the CdS nanowires crystallize in an hcp structure. Besides, photoluminescences(PL) of CdS nanowire arrays, characterized by spectrophotometer show that CdS nanowries embedded in porous alumina template increases the light-emitting intensity and induces a red shift of PL band.  相似文献   

8.
采用乳液共聚法制备了聚苯乙烯-丙烯酸羟乙酯[P(St-HEA)]微球,通过流延成膜法制备了P(St-HEA)薄膜,再利用溶胶-凝胶模板法煅烧得到有序多孔二氧化铈(CeO2)薄膜.采用红外光谱、扫描电镜以及X射线衍射分析对P(St-HEA)微球单分散性及有序多孔CeO2薄膜表面形貌和结构进行了表征.结果表明,当丙烯酸羟乙酯(HEA)用量占总单体的用量低于10%(质量分数)时,制备的P(St-HEA)微球单分散性和表面较好.通过P(St-HEA)的胶体晶体模板制备了有序多孔CeO2薄膜,所得孔径约为190 nm,X-射线衍射分析显示有序多孔CeO2薄膜是立方萤石结构.  相似文献   

9.
利用多孔氧化铝模板电沉积法成功地制备了α铁相纤维阵列。结果表明:此法制备的铁纤维直径约为300nm,纤维长度随电沉积时间的增加而增加;铁纤维长径比增加会使单位面积饱和磁化强度(Ms)增大、矫顽力(Hc)减小。  相似文献   

10.
铜导线中晶界对导电性影响的研究   总被引:2,自引:1,他引:2  
通过设计不同的退火温度,得到了含不等晶界数的铜导线,以此研究了晶界对导电性的影响。测量结果表明:导线的电阻率随晶界数的增加而增加,这归结于晶界对传导电子的散射作用;晶界对电阻率的影响并不象空位、位错那样呈简单的线性关系,而是呈指数关系;晶界控制导线电阻率变化曲线的总趋势,而具体细节则由杂质的类型和数量来控制。  相似文献   

11.
阳极氧化工艺对氧化铝模板孔径的影响   总被引:1,自引:0,他引:1  
为了能制备出有序的纳米线阵列,采用一次阳极氧化的方法,制备出了孔径在12.8~43.5nm之间的多孔有序的氧化铝模板.通过改变氧化液浓度、氧化电压、氧化温度等条件,可对氧化铝模板的孔径大小进行控制,对各阳极氧化工艺因数对模板孔径的影响机理也进行了分析讨论.结果表明,在较低的氧化液浓度,氧化电压和氧化温度条件下,氧化铝膜的孔径较小;而在高的氧化液浓度,氧化电压和氧化温度条件下,氧化铝膜的孔径较大.  相似文献   

12.
Ni nanoparticles plating was prepared in reverse microemulsion. The deposition was carried out through the Brownian motion of water pools in the reverse microemulsion and the adsorption of water pools on the electrode surface. Effects of electrolytic parameters on the size of Ni particles were studied. The performances of hydrogen evolution and hydrogen storage of the Ni nanoparticles plating electrode were also investigated. The results indicate that the size of Ni nanoparticles decreases with the increase...  相似文献   

13.
Preparation and Optical Properties of V2O5 Nanotube Arrays   总被引:1,自引:0,他引:1  
V2 O5 nanotube arrays in porous atomic alumina ( PAA ) template were obtained from V2O5 sols prepared by melt quenching method. X-ray powder diffraction and selected area electron diffraction investigations demonstrate that V2O5 nanotubes are orthorhombic. Results by scanning electron mieroscopy and transmission electron microscopy results shove that V2O5 nanotubes with a uniform diameter form highly ordered arrays. The diameter and length of the nanotubes depend on the pore diameter and the thickness of the PAA template used. It is proved that the sol-gel template process is a cost-saving , simple and readily-controlled method to prepare metal oxides nanomaterials .Owing to the quantum size effect. the optical absorption edge of V2O5 nanotubes in PAA ehibits a significant blue shift with respect to that of bulk V2O5.  相似文献   

14.
镍基纳米碳管/二氧化钛复合镀层的制备及性能   总被引:1,自引:0,他引:1  
为了改善金属基材的表面性能,以钛铁矿为原料,利用微波等离子体化学气相沉积法制备了纳米碳管/二氧化钛复合粉体.采用复合电泳电沉积法在不锈钢基体表面制备了镍基纳米碳管/二氧化钛复合镀层;利用扫描电镜、X射线衍射仪、数显维氏硬度计和电化学测试等手段研究了纳米碳管/二氧化钛复合粉体对复合镀层结构和性能的影响.结果表明纳米碳管/二氧化钛复合粉体的加入有效地减小了复合镀层中镍的晶粒尺寸,促进了金属镍沿(111)晶面择优取向生长,改变了镍的电沉积层结构,提高了镀层的硬度,改善了镀层的耐腐蚀性能;在复合粉体的作用下,复合镀层的硬度与纯镍镀层相比提高了110%,腐蚀电位正移了23mV,腐蚀电流密度减少了0.991微安/平方厘米.  相似文献   

15.
Underthepressureofincreasinglystrictenvironmen tallawandthestimulationoftechnicaladvancement,hy drometallurgyofcopperhasgotenormousdevelopmentworldwide[1 3] .Nowtotalthroughputofcopperbyhy drometallurgyisincreasingby 2 5%annually .In 1998,thetotalthroughputachie…  相似文献   

16.
通过PMMA胶体晶体模板法制备了有序的SiO2多孔材料.首先采用两阶段加料的无皂乳液聚合方法,成功地合成了单分散的甲基丙烯酸改性聚甲基丙烯酸甲酯微球,然后将聚合合成的胶乳在一定温度下蒸发一段时间使单分散微球组装成大面积的有序胶体晶体,再以硅溶胶填充胶体晶体,经干燥后煅烧去掉PMMA胶体晶体模板等过程制备较大面积有序的SiO2多孔薄膜.粒径分析、紫外-可见光透过光谱图分析结果表明:所制备的甲基丙烯酸改性聚甲基丙烯酸甲酯微球为单分散且粒径为250nm左右.扫描电镜、热失重、红外光谱等分析结果表明:SiO2多孔材料孔洞规则排列、相互连接、较好的复制了胶体晶体的有序结构,孔径分布在250nm左右.  相似文献   

17.
溶胶凝胶法制备TiO2多孔纳米薄膜   总被引:1,自引:0,他引:1  
用溶胶凝胶法在普通载玻片上成功地制得 Ti O2 多孔纳米薄膜。研究了 Sol- Gel工艺参数和不同烧结温度对材料结构和物相的影响。结果表明 :Ti O2 在室温至 80 0℃之间经历无定形态→锐钛矿→锐钛矿与金红石共存→金红石的相变过程 ,制备出了孔径范围 75~ 80 0 nm的 Ti O2 多孔纳米薄膜  相似文献   

18.
以低分子量聚丙烯酸(PAA)为高分子模板构建自组装体系,合成核-壳结构的PAA/PbCrO4纳米颗粒.通过TEM、XRD、FT-IR、UV-vis、荧光光谱等表征手段对产物的结构、形貌与光学性能进行研究.结果表明:PAA通过羧基与Pb2+的配位作用包覆在PbCrO4纳米颗粒表面,形成核-壳结构,内核PbCrO4尺寸为50~100 nm,为单斜晶系;外壳PAA层厚20 nm.与普通PbCrO4体相材料相比,产物在829~854 cm-1红外吸收峰变宽,紫外与荧光光谱产生了"蓝移",表现出纳米粒子所具有的特殊光学现象.  相似文献   

19.
Porous ZnO films were prepared by electrodeposition method in zinc nitrate aqueous solution using ITO glass covered with polystyrene sphere (PS) colloidal crystal arrays as substrates. The preparation procedure includes two parts: deposition of ZnO in the interstices of the colloidal crystals and subsequent removal of the PS templates. The influences of deposition potential and temperature on the ZnO films were investigated. The ordered, uniform porous ZnO films with optical transmittance of approximately 63.6% at 600 nm could be obtained when the deposition potential and temperature were –1.1 V and 70 ℃, respectively. The optical band gap energy increased along with the absolute deposition potential and temperature, ranging from 3.33 to 3.43 eV and from 3.35 to 3.42 eV, respectively.  相似文献   

20.
以水/SDBS/Span-80/Tween-80/HL68微乳液体系,采用还原法在润滑油中成功制备出了油溶性良好的纳米金属铜粒子;SEM及TEM分析表明,纳米铜呈球形,有部分团聚,粒径分布在10b20nm.分别从表面活性剂的选取、微乳液分散方法、反应温度等方面,研究了在该体系下制备纳米金属铜的适宜工艺条件.  相似文献   

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