Fabrication of porous bismuth by electrochemical dealloying of Sn–Bi alloys: From microporous structures to nanowire matrix composites

The fabrication of three-dimensional (3D) porous bismuth by electrochemical dealloying of two-phase Sn–Bi alloys was investigated. The results show that the resulting porous bismuth changes from a microporous structure composed of bismuth microparticles to an aligned nanowire matrix composite as the Bi content in the Sn–Bi master alloy decreases. Single-crystal bismuth nanowires growing in the [110] direction were fabricated by the selective dissolution of the Sn phase from an alloy with ultralow Bi content. The influence of the two states of elemental Bi existing in smelted Sn–Bi alloys during dealloying was systematically analyzed and discussed. This report presents a novel strategy for direct fabrication of bismuth nanowires by electrochemical dealloying.     

双极纳米电极阵列实现单个铂纳米颗粒上氢气析出反应的电致化学发光成像

本文制备了嵌于多孔阳极氧化铝（AAO）膜中直径为200 nm,间距为450 nm的高密度（5.7 × 10⁸ cm^-2）的金纳米电极阵列,纳米电极分布规则,尺寸高度均一。我们将该金纳米电极阵列作为双极电极阵列,可将电极一侧的电化学法拉第信号在另一侧电极上转化成电致化学发光（ECL）信号,从而实现对单个铂纳米颗粒上氢气析出反应（HER）进行亚微米空间分辨率的电化学成像。本文介绍的方法为高空间分辨率成像电催化材料、能源材料以及细胞过程的局部电化学活性提供了一个良好的平台。     

聚吡咯/硫化镉核壳纳米线的制备及整流特性

以无机多孔氧化铝膜为模板,利用气相沉积和原位电化学沉积方法成功地制备了有机-无机杂化聚吡咯/硫化镉核壳纳米线;采用扫描电子显微镜和透射电子显微镜分析了聚吡咯/硫化镉核壳纳米线的表面形貌和微结构.结果表明,内部的聚吡咯纳米线紧紧依附在外部的硫化镉纳米管中,并且硫化镉纳米管被聚吡咯全部填充.与此同时,在聚吡咯/硫化镉核壳纳米线中,外部硫化镉壳与内部聚吡咯核之间存在电荷转移;聚吡咯和硫化镉之间形成有机-无机杂化的P-N界面,从而导致单根聚吡咯/硫化镉核壳纳米线显示出不同于外部壳和内部核的整流特性.     

Sb有序单晶纳米线阵列的制备

采用直流电沉积的方法在氧化铝模板（AAM）中成功地制备了Sb单晶纳米线阵列. X射线衍射（XRD）证明所制得的纳米线阵列为(110)取向的六方相Sb.透射电镜（TEM）显示Sb纳米线平滑而均匀,直径40～50 nm,长径比大于1000.选区电子衍射（SAED）结果表明,所制得的纳米丝为Sb单晶丝.场发射扫描电镜（FE-SEM）显示Sb纳米线阵列规则,填充率接近100％.     

PS-b-PEO模板法制备Pt纳米线

以PS-b-PEO纳米孔膜为基体电极,采用电沉积技术制备了Pt纳米线,用扫描电化学显微镜(SECM)、扫描电镜(SEM)和X-射线能谱(EDS)分析法表征了基体电极和Pt纳米线。利用循环伏安法考察了Pt纳米线的电化学性能。实验结果表明,Pt纳米线对甲酸氧化表现出优异的电催化活性。此外,Pt纳米线具有良好的稳定性和重现性,可望用于实际样品中甲酸的测定。     

Size Effects on the Luminescence Properties of Polymer Nanowires简

Poly（3-（2-methoxyphenyl）thiophene） （PMP-Th） nanowires were fabricated using porous anodic alumina （PAA） as template through electrochemical polymerization by cyclic voltammetry. The control on the size of nanowires was confirmed by electron microscopy. The results indicated that the luminescence spectra of PMP-Th nanowires in PAA nanochannels were blue-shifted and emission intensity was enhanced compared to the emission of the PMP-Th film. Moreover, the luminescent spectra of PMP-Th nanowires were size dependent, which may result from the change in the degree of confinement of nanowires in PAA. F6rster energy transfer from PAA to PMP-Th molecules is considered to be responsible for the enhancement of luminescence from PMP-Th nanowires in PAA. The results show that the emission properties of polymers with nanostructures can be tuned by controlling their size.     

钴纳米线的模板制备与磁性

利用二次阳极氧化法制备了多孔阳极氧化铝模板. 用直流电化学沉积方法成功地在模板孔道内制备了钴纳米线. 采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)和振动样品磁强计(VSM)对样品的形貌、晶体结构和磁性进行了研究. 结果表明， 模板的孔径均匀, 孔道平直. 钴纳米线为多晶的六方密堆积结构. 钴纳米线具有明显的磁各向异性, 这主要起源于纳米线的形状各向异性.     

导电聚吡咯纳米线的电化学无模板法可控合成与表征

以β-萘磺酸(NSA)为掺杂剂,采用电化学无模板法制备了聚吡咯(PPy)纳米线.研究了NSA浓度、吡咯(Py)单体浓度及反应温度对PPy纳米线形貌的影响.分别采用场发射扫描电子显微镜(FE-SEM)和拉曼光谱对PPy纳米线的结构形貌和化学结构进行了表征.结果表明,利用电化学无模板法可得到中空的PPy纳米线;NSA浓度会影响PPy纳米线的取向性;增大Py单体浓度,可制得圆锥状PPy纳米线;低温有利于合成形状细长、紧密堆积的PPy纳米线.PPy纳米线形貌受游离Py浓度及Py-NSA胶束数量影响,通过调节NSA浓度、Py浓度及反应温度改变游离Py浓度及Py-NSA胶束数量,可制得不同形貌的PPy纳米线.     

纳米金属多层膜与多层纳米线的电化学制备及其表征

分别采用单槽法和双槽法电沉积Cu/Co多层膜.研究了两种电沉积方法制备多层膜的工艺条件,利用电化学方法、XRD和SEM对多层膜进行表征,并对Cu/Co多层膜的巨磁阻性能进行了测试. 采用电沉积多层膜的方法，以多孔铝阳极氧化膜（AAO）为模板,在纳米孔内沉积Cu/Co多层线,采用TEM对多层纳米线进行了表征.     

Hot spots in silver nanowire bundles for surface-enhanced Raman spectroscopy

We report a simple strategy for placing analyte molecules in hot spots between closely spaced nanowires leading to intense SERS enhancement. The results are highly reproducible from experiment to experiment likely because of the regularity of the SERS substrate, which consists of highly ordered and regular silver nanowires fabricated in porous aluminum oxide. Because the silver nanowires are sealed in the pores of PAO, this system is potentially immune to contamination until it is ready for use, at which point the alumina matrix is etched, thereby allowing the silver nanowires to collapse into bundles and form hot spots in the region of close contact between the nanowires, trapping the analyte in those junctions.     

Fabrication and electrochemical behaviour of vertically aligned boron-doped diamond nanorod forest electrodes

Vertically aligned boron-doped diamond nanorod forests (BDDNF) were successfully fabricated by depositing a diamond film onto silicon nanowires (SiNWs) using hot filament chemical vapor deposition (HFCVD). The boron-doped diamond nanorods were characterized by Raman spectroscopy and scanning electron microscopy (SEM). The BDDNF obtained from the SiNWs on the silicon wafer could be directly used as an electrode and its electrochemical behaviour is discussed here. Compared to a flat boron-doped diamond (BDD) electrode, the BDDNF electrode showed high sensitivity in the amperometric detection of adenine.     

吡啶在几种金属纳米线阵列上的表面增强喇曼光谱

近20多年来利用表面增强喇曼光谱（SERS）的研究还仅限于Ag,Au,Cu这三种具有强SERS效应的金属,最近,田中群等利用合适的表面处理方法和共焦曼光谱技术成功地获得了许多无机离子和有机小分子吸附在一系列的过渡金属（如Pt,Ni,Fe,Pd,Rh,Co,Ru等）上的SERS光谱,拓宽了SERS的应用范围,但这些表面处理方法对基底进行处理时存在着较大的随机性,从而导致对所得SERS信号的解释困难。近年来通过自组装膜、模板合成等技术可得比较有序具有强SERS效应的或表面,例如Nie等最近发现尺寸分布狭窄的Ag溶胶粒子（约80－100nm）能诱导出巨大的SERS增强;Freeman和C tffumj m jf rbutb uqf At A 体微粒组装在聚合物基底上,制得高活性的SERS基底,以上工作都表明制备有序纳米级金属颗粒表面将推动SERS的应用和机理研究,迄今,3半导体纳米线阵列上的喇曼光谱已有报道,而利用金属纳米线阵列作为SERS基底除半于样模合成法制备的Ag纳米线阵列上的SERS之外,尚未见其它相关报道,本文主要研究样模合成法制备金属纳米线的过程,并以此为基底研究吡啶吸附的SERS光谱。     

Structural, magnetic, and magnetoresistive properties of electrodeposited Ni5Zn21 alloy nanowires

Ni5Zn21 alloy nanowires were fabricated through template-assisted electrochemical deposition method. The morphology and microstructures of as-deposited nanowires were determined by field-emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM), electron diffraction (ED), and electron probe microanalysis (EPMA). The accurate composition was measured via induced coupling plasma atomic emission spectroscopy. SEM results show that Ni5Zn21 nanowires are deposited in most of the nanopores of the template, and they are continuous and dense throughout the whole length. The XRD result demonstrates that the nanowires are mainly composed of a cubic gamma phase Ni5Zn21 alloy, but there also exists a trace of Zn-rich eta phase. HRTEM and ED reveal that the alloy nanowires are polycrystalline with the crystallite size of several tens of nanometers. EPMA of a single nanowire illustrates that there exist Ni-rich microzones in as-deposited nanowires. Subsequent magnetic measurements of the array also confirmed the existence of them. In addition, it can be further inferred that the shape of Ni-rich microzones is probably barlike or disklike, from the anisotropy of zero field cooling/field cooling (ZFC/FC) curves as well as the vortex magnetization behavior of the Ni5Zn21 nanowire array. The low-temperature magnetoresistance of the Ni5Zn21 nanowire array was also measured. Giant magnetoresistance instead of anisotropic magnetoresistance is suggested to be responsible for contributing to the magnetoresistance.     

Synthesis and Electrochemical Properties of Highly Crystallized CuV2O6 Nanowires

CuV₂O₆ nanowires were prepared via a simple hydrothermal route using NH₄VO₃ and Cu(NO₃)₂ as starting materials. The structures and electrochemical properties of CuV₂O₆ nanowires were characterized by means of X-ray diffraction(XRD), scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The results show that the CuV₂O₆ nanowires are about 100 nm in width and single crystalline grown along [001] direction. CuV₂O₆ nanowires delivered a high initial discharge capacity of 435 and 351 mA·h/g at current densities of 50 and 100 mA·h/g, respectively. The electrochemical kinetics of the CuV₂O₆ nanowires was also investigated by means of electrochemical impedance spectroscopy(EIS) and the poor rate performance was observed, which may be attributed to the low ion diffusion coefficient of the CuV₂O₆ nanowires.     

Insulin amyloid fibrils: an excellent platform for controlled synthesis of ultrathin superlong platinum nanowires with high electrocatalytic activity

Highly uniform single-crystal ultrathin Pt nanowires (UTPtNWs) with a diameter of ~1.8 nm and a superhigh aspect ratio of >10(4) were fabricated using insulin amyloid fibrils (INSAFs) as sacrificial templates. The use of INSAFs to build the UTPtNWs allowed for the preferential exposure of low-energy crystal facets that would be highly advantageous for the methanol oxidation reaction. The UTPtNWs displayed a large electrochemical active surface area of 71.34 m(2)/g, which is much higher than that of a commercial Pt/C catalyst. The UTPtNWs also maintained excellent electrochemical durability under repeated cyclic voltammetry scans. Because of its exciting high electrochemical activity, UTPtNWs is a promising material for the design of next-generation electrocatalysts and would also be useful in sensing, biomedical, and other electrochemical applications.     

Microstructuring of p-Si(1 0 0) by localized electrochemical polishing using patterned agarose as a stamp

Localization of electrochemical polishing using patterned agarose has been employed to fabricate microstructures on p-Si(1 0 0). The patterns were first transferred from a master to an agarose stamp, and then the microstructures were fabricated by limiting electrochemical polishing in the small contact area between the stamp and the workpiece. The gel stamp acts as the current flow channel between the working electrode and the counter electrode, simultaneously directing the electrolyte to the preferential parts of the Si workpiece. Microstructures fabricated by partial anodic dissolution on p-Si are approximately the same as those on the master. Lateral deviation of the fabricated microstructures from those on the master is approximately 2.6% and the electrochemical etching rate in HF is around several micrometers in an hour. This newly developed technique can be used as a low-cost and simple approach to fabricate microstructures on p-Si with high fidelity at a fast rate.     

Anisotropic swelling of hydrogel nanowires based on poly(vinylpyrrolidone) fabricated by single‐particle nanofabrication technique

We report a hydrogel nanowire based on poly(vinylpyrrolidone) (PVP) and N,N'‐methylenebis(acrylamide) (MBA), which have anisotropic swelling ratio for radius and length direction. The PVP/MBA nanowires were fabricated by single particle nanofabrication technique, which is a technique for the fabrication of polymeric nanowires using the single ion event, that cause the crosslinking reaction of polymer chains within the ion tracks along the ion paths; furthermore the size (length and radius) of the nanowires was controlled by changing the film thickness and amount of MBA crosslinker. The swelling behaviors in air and water were observed using atomic force microscopy. The PVP/MBA nanowires exhibited anisotropic swelling along the length and radius in aqueous environments, because the hydrogel nanowires consisted of crosslinked networks with inhomogeneous crosslinking points, which reflected the initial energy distribution from incident an ion within the ion track. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1950–1956     

硅基多孔氧化铝模板非水电沉积CdS纳米线的研究

纳米材料,包括尺寸为纳米量级的超细微粒?线?薄膜?量子阱和超晶格等引起了人们广泛的重视 [1,2] ?其中 , 半导体纳米微粒和由其构成的纳米固体结构开辟了材料科学研究的新领域?硫化镉 (CdS) 作为一种重要的Ⅱ - Ⅵ族无机半导体材料 , 具有独特的光电性质 , 在光电化学电池和多相光催化反应中都有广泛应用?近年来 , 已有大量关于合成 CdS 纳米结构的文献报导 [3～12] , 所采用的方法如反胶束法?单分子膜法?自组装法以及电化学沉积法等 , 其中非水电解与模板技术相结合的制备方法引起了人们高度的重视并且被广泛的采用?自从 Baranski 等在上…     

Single tungsten nanowires as pH sensitive electrodes

The electrochemical potentials of tungsten nanowire samples, covered with their own oxide, were measured in dependence of the pH value. The samples were prepared by selective etching of a directionally solidified eutectic NiAl–W alloy. Directional solidification in a Bridgman-type crystal growth furnace yields nanostructured two-phase materials. Electrochemical processing allows selective etching of the phases exposing the nanoscale structures. In this work, pointed samples with a single wire 200 nm in diameter protruding from the tip were produced. Subsequently the tungsten oxide layer on these single nanowires was electrochemically modified to optimize their pH sensing capabilities. The method has a potential for further downsizing since the wire diameter and exposed length can be controlled by the process parameters during solidification and during electrochemical processing. The advantages of these nanowire pH probes along with possible applications such as the pH measurement in ultra small cavities and other small systems of interest such as corrosion pits and biological cells are discussed.     

Edge plane sites on highly ordered pyrolytic graphite as templates for making palladium nanowires via electrochemical decoration

An approach for the fabrication of metal nanowires is presented. Palladium wires with diameters less than 50 nm were produced by electrochemical decoration of step edge sites on the surface of highly ordered pyrolytic graphite via the following three steps. First an electrochemical activation step was used to oxidize the edge plane sites on highly ordered pyrolytic graphite surfaces in 0.5 M Na(2)SO(4). Second, a potential cycling step in a 1 mM PdCl(2) solution in 0.1 M H(2)SO(4) was used to form palladium oxide (s) and/or complexes of Pd on the step edges. Third, Pd nanowires were formed by electroreduction after transfer of the graphite to 0.1 M H(2)SO(4). The resulting wires showed a high degree of uniformity. A merit of this approach is that it allowed metal nanowires to be fabricated without the simultaneous formation of nanoparticles on the basal plane terraces, in contrast to other studies of this type. The mesoscopic palladium wires are shown to be useful for the electrochemical sensing of hydrazine.