Growth and morphological analysis of segmented AuAg alloy nanowires created by pulsed electrodeposition in ion-track etched membranes

• Ina Schubert,
• Loic Burr,
• Christina Trautmann and
• Maria Eugenia Toimil-Molares

Beilstein J. Nanotechnol. 2015, 6, 1272–1280, doi:10.3762/bjnano.6.131

• wires have also great potential as electronic components [7] and, thus, Au nanowires separated by small gaps are very promising as nanowire electrodes that can be used as field effect transistors [48] and for the capture and electrical characterization of nanoparticles [49]. For all these applications

• , the length of the segments plays a determining role and, thus, the length distribution achieved during the simultaneous growth of nanowire arrays should be analysed and discussed in detail. In this work, we synthesise segmented AuAg alloy nanowires by pulsed electrodeposition in track-etched membranes

• containing only 0.25 M Na2CO3 (black line) was measured. In all cases a Au rod served as working electrode. This Au rod is chosen, since also during nanowire deposition, we use a Au layer of sputtered Au on the membrane rear side as working electrode. During the process, the voltage is ramped from −0.1 to

Preparation of Ni/Cu composite nanowires

• Hu Wang,
• Xiaoyu Li,
• Ming Li,
• Kenan Xie and
• Li Liao

Beilstein J. Nanotechnol. 2015, 6, 1268–1271, doi:10.3762/bjnano.6.130

• and Figure 1d, respectively. It is obvious that Ni nanowires (Figure 1c) of about 200 nm in diameter with a relatively smooth surface were obtained before being used as template. Figure 1d shows the surface morphology of the Ni/Cu composite nanowires, from which a straight clubbed nanowire could be

Patterning technique for gold nanoparticles on substrates using a focused electron beam

• Takahiro Noriki,
• Shogo Abe,
• Kotaro Kajikawa and
• Masayuki Shimojo

Beilstein J. Nanotechnol. 2015, 6, 1010–1015, doi:10.3762/bjnano.6.104

• performed using nanowires placed on substrates without regard to their position. It is difficult to produce a branched nanowire with a designed shape and to place the nanowire at a desired position at the nanoscale. It has been theoretically demonstrated that a plasmon can propagate through a chain of

Combination of surface- and interference-enhanced Raman scattering by CuS nanocrystals on nanopatterned Au structures

• Alexander G. Milekhin,
• Nikolay A. Yeryukov,
• Larisa L. Sveshnikova,
• Tatyana A. Duda,
• Ekaterina E. Rodyakina,
• Victor A. Gridchin,
• Evgeniya S. Sheremet and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2015, 6, 749–754, doi:10.3762/bjnano.6.77

• optical (SO) and LO phonon modes in a CdSe core and the transverse optical (TO) phonon mode in a ZnS shell of core–shell CdSe/ZnS NCs attached to the surface of a Au nanowire. The spectrum of optical and interface phonons was obtained from the analysis of SERS spectra of pure CdSe NCs, core–shell CdSe/CdS

Simple approach for the fabrication of PEDOT-coated Si nanowires

• Mingxuan Zhu,
• Marielle Eyraud,
• Judikael Le Rouzo,
• Nadia Ait Ahmed,
• Florence Boulc’h,
• Claude Alfonso,
• Philippe Knauth and
• François Flory

Beilstein J. Nanotechnol. 2015, 6, 640–650, doi:10.3762/bjnano.6.65

• pulsed electrodeposition technique. N-type Si nanowire (SiNWs) arrays were synthesized using an electroless metal-assisted chemical etching technique. The dependence of the SiNW reflection on the concentration of the AgNO3 solution was identified. A reflection of less than 2% over the entire visible

• nanowire density on the substrate. For a tapering time of less than 30 s, the reflectance does not show significant change: a 10 s tapering leads to a reflection of less than 5% and a 30 s tapering to a reflection of less than 6%. This suggests that there is still a strong light trapping effect in the

• in a dark environment. Tilted-view, SEM observations of SiNW samples without tapering (a) and for different tapering times: (b) 10 s, (c) 30 s, (d) 50 s. TEM image of a silicon nanowire obtained using the same conditions as those in Figure 1a. Reflection spectra of SiNWs in the visible spectral range

Filling of carbon nanotubes and nanofibres

• Reece D. Gately and
• Marc in het Panhuis

Beilstein J. Nanotechnol. 2015, 6, 508–516, doi:10.3762/bjnano.6.53

• is still very much prevalent today. The main advantages of using CNTs to produce metallic nanowires is that the CNTs act as a template for self-assembly of the nanowires [40][41] and the CNT structure can act as a protective sheath to protect the nanowire from being damaged by chemicals in harsh

• gold electrodes [72]. This was shown to not only decorate the external surface, but also to fill some MWCNTs with a gold nanowire. Ordered, open MWCNTs produced from the AAO template method have also undergone an electrochemical filling process with nickel–iron alloys [73]. It was shown that this

Electrical properties of single CdTe nanowires

• Elena Matei,
• Camelia Florica,
• Andreea Costas,
• María Eugenia Toimil-Molares and
• Ionut Enculescu

Beilstein J. Nanotechnol. 2015, 6, 444–450, doi:10.3762/bjnano.6.45

• [13]. This method allows for control of pore density by taking into account that each ion leaves a single, cylindrical track and pore size throughout the etching process. These parameters are usually chosen in connection with the desired final nanowire size and quantity. Electrochemical deposition is

• combination of lithography and focused ion beam-induced metallization (FIBIM). The electrical properties were determined for individual nanowires prepared under different conditions. Further, the effect of a bottom gate on the charge carriers transported through the nanowire channel was examined. It was also

• nanowire suspension was placed on Si/SiO2 substrates on which interdigitated Ti/Au electrodes were patterned by photolithography (Figure 4). FIBIM is a direct patterning method employed for the design of metallic nanostructures. The method is based on the interaction of an ion beam with the surface

Tunable white light emission by variation of composition and defects of electrospun Al₂O₃–SiO₂ nanofibers

• Jinyuan Zhou,
• Gengzhi Sun,
• Hao Zhao,
• Xiaojun Pan,
• Zhenxing Zhang,
• Yujun Fu,
• Yanzhe Mao and
• Erqing Xie

Beilstein J. Nanotechnol. 2015, 6, 313–320, doi:10.3762/bjnano.6.29

• crystallinity. The interplanar spacing of 0.5495 nm measured from the legible lattice fringes along the axis of the nanowire is quite similar to that of the <110> planes of the mullite crystals [27][28]. In addition, some nanocrystals of cristobalite with dimensions of several tens of nm can also found on the

Localized surface plasmon resonances in nanostructures to enhance nonlinear vibrational spectroscopies: towards an astonishing molecular sensitivity

• Dan Lis and
• Francesca Cecchet

Beilstein J. Nanotechnol. 2014, 5, 2275–2292, doi:10.3762/bjnano.5.237

• (Figure 4d). Figure 5 shows the nonlinear emission of a rectangular gold nanowire illuminated simultaneously with two laser pulses at ω1 = 817 nm and ω2 = 1064 nm [32][59]. The blue spectrum plots the collected light intensity with an incident light polarization perpendicular to the wire axis, matching

Cathode lens spectromicroscopy: methodology and applications

• T. O. Menteş,
• G. Zamborlini,
• A. Sala and
• A. Locatelli

Beilstein J. Nanotechnol. 2014, 5, 1873–1886, doi:10.3762/bjnano.5.198

• function. When the photon energy is tuned to the Fe absorption threshold (middle panel), the elongated Fe nanowires become much brighter, whereas the regions in between barely change intensity. The spectrum seen in the plot in Figure 3a is extracted from an individual nanowire. Magnetic imaging. X-ray

• nanowires on W(110) appear dark on the left panel at a photon energy of 704.5 eV. At the Fe L3 threshold, the wires become much brighter (middle panel). The XAS spectrum below is extracted from the largest nanowire in the center. b) Illustration of XMCD-PEEM imaging. The photon energy is tuned to the L3

• maximum. The field of view is 5 μm. The start voltage is 3 eV in order to collect secondary electrons. Within the image plane, the X-ray direction is perpendicular to the nanowire axis. The SPELEEM instrument at the Nanospectroscopy beamline, Elettra Sincrotrone, Trieste. The sketch of the basic setup is

Room temperature, ppb-level NO₂ gas sensing of multiple-networked ZnSe nanowire sensors under UV illumination

• Sunghoon Park,
• Soohyun Kim,
• Wan In Lee,
• Kyoung-Kook Kim and
• Chongmu Lee

Beilstein J. Nanotechnol. 2014, 5, 1836–1841, doi:10.3762/bjnano.5.194

• temperatures. In this study, ZnSe nanowires were synthesized by the thermal evaporation of ZnSe powders and the sensing performance of multiple-networked ZnSe nanowire sensors toward NO2 gas was examined. The results showed that ZnSe might be a promising gas sensor material if it is used at room temperature

• enhance the sensing performance of ZnSe, 1D nanostructure-based sensors at room temperature. In this study, multiple-networked ZnSe nanowire sensors were fabricated and examined for their room-temperature, NO2-gas sensing properties under UV illumination. Unlike individual 1D nanostructure sensors

• reflection peaks assigned to wurtzite-structured ZnSe with lattice constants of a = 0.3996 nm and c = 0.6626 nm (JCPDS No. 89-2940), suggesting that the nanowires were crystalline. The low-magnification TEM image in Figure 2a revealed a typical ZnSe nanowire with an extremely uniform diameter of

Probing the electronic transport on the reconstructed Au/Ge(001) surface

• Franciszek Krok,
• Mark R. Kaspers,
• Alexander M. Bernhart,
• Marek Nikiel,
• Benedykt R. Jany,
• Paulina Indyka,
• Mateusz Wojtaszek,
• Rolf Möller and
• Christian A. Bobisch

Beilstein J. Nanotechnol. 2014, 5, 1463–1471, doi:10.3762/bjnano.5.159

• other nanowire structures, e.g., in atoms on Si(111) [4] or Au on Si(557) [5], the Au/Ge(001) wires are rather robust against a Peierls distortion [6], so that the Au/Ge(001) surface offers the unique opportunity to study a Tomonaga–Luttinger liquid. In addition, such atomic scale wires may be used as

Review of nanostructured devices for thermoelectric applications

• Giovanni Pennelli

Beilstein J. Nanotechnol. 2014, 5, 1268–1284, doi:10.3762/bjnano.5.141

• properties on one side and material availability, sustainability, technological feasibility on the other side. The most important bottom-up and top-down nanofabrication techniques for large area silicon nanowire arrays, to be used for high efficiency thermoelectric devices, will be presented and discussed

• . Moreover, the electrical conductivity of very small nanostructures is strongly reduced by the surface scattering of charge carriers. As an example, Figure 5 shows the Seebeck coefficient evaluated for silicon nanowires with triangular cross section [18], as a function of the nanowire width (triangular base

• ) W: S increases only if the nanowire width is reduced below 5 nm. It is to be noted that S increases noticeably for low doping values, because the Fermi energy level decreases with respect to the bottom of the conduction band, and consequently the energy difference between charge carriers and Fermi

Methods for rapid frequency-domain characterization of leakage currents in silicon nanowire-based field-effect transistors

• Tomi Roinila,
• Xiao Yu,
• Jarmo Verho,
• Tie Li,
• Pasi Kallio,
• Matti Vilkko,
• Anran Gao and
• Yuelin Wang

Beilstein J. Nanotechnol. 2014, 5, 964–972, doi:10.3762/bjnano.5.110

• 10.3762/bjnano.5.110 Abstract Silicon nanowire-based field-effect transistors (SiNW FETs) have demonstrated the ability of ultrasensitive detection of a wide range of biological and chemical targets. The detection is based on the variation of the conductance of a nanowire channel, which is caused by the

• methods is verified by experimental measurements from an n-type SiNW FET. Keywords: admittance spectroscopy; excitation design; frequency characterization; frequency response; silicon nanowire; Introduction Recent development in sensing biochemical molecules has been rapid. Among many sensing

• technologies, silicon nanowire (SiNW)-based field-effect transistors (FETs) [1] are one of the most promising building blocks for the next generation of electrical circuits in recognizing a wide range of biological and chemical targets. They have been successfully used in the detection of DNA [2], pH [3

Designing magnetic superlattices that are composed of single domain nanomagnets

• Derek M. Forrester,
• Feodor V. Kusmartsev and
• Endre Kovács

Beilstein J. Nanotechnol. 2014, 5, 956–963, doi:10.3762/bjnano.5.109

• anisotropy provides the preferential orientation of segmented magnetic moments along the nanowire), understanding the magnetic phases has never been more timely. Indeed, by the experimental studying of the magnetic hysteresis of these nanosized stacks the different magnetic regimes described herein can be

Integration of ZnO and CuO nanowires into a thermoelectric module

• Dario Zappa,
• Simone Dalola,
• Guido Faglia,
• Elisabetta Comini,
• Matteo Ferroni,
• Caterina Soldano,
• Vittorio Ferrari and
• Giorgio Sberveglieri

Beilstein J. Nanotechnol. 2014, 5, 927–936, doi:10.3762/bjnano.5.106

• present the fabrication by simple and low-cost physical methods of both n- and p-metal oxide nanowires in order to build a prototype of planar thermoelectric unit based on metal oxide nanowire arrays, targeting different applications ranging from radioisotope thermoelectric generators [14][15][16] to

• , with the overall effect of increasing the total electrical resistance of the device. A reduction in the nanowire length will increase the number of junctions that charge carriers have to face within the entire extension of the mat, thus increasing the total electrical resistance and reducing the

• limitations related to the growth technique. The voltage drop ΔV across the sample has been measured as a function of the applied temperature difference ΔT. Figure 1c shows the dependence of the temperature difference ΔT and the corresponding voltage ΔV measured for ZnO nanowire samples as a function of time

Nanostructure sensitization of transition metal oxides for visible-light photocatalysis

• Hongjun Chen and
• Lianzhou Wang

Beilstein J. Nanotechnol. 2014, 5, 696–710, doi:10.3762/bjnano.5.82

• greatly prolonged lifetime of photoexcited carriers [36]. We also investigated the photoelectrochemical behavior of CdS sensitized TiO2 film with {001} facet enriched anatase nanocrystals [37]. Zhang et al. developed a double-sided CdS and CdSe quantum dot co-sensitized ZnO nanowire arrayed photoanode for

• photoelectrochemical hydrogen generation [38]. As shown in Figure 4, the scheme shows that the quantum dots of CdS and CdSe on both sides of ITO can be excited and transfer electrons to the ZnO nanowire array. The CB edges of CdS and CdSe are higher than that of ZnO (Figure 4b). Due to this unique configuration and

• the band alignment between CdS and CdSe, the co-sensitized ZnO nanowire arrayed photoanode exhibited almost the entire visible-light absorption and fast electron transfer from CdSe quantum dots to ZnO nanowires and thereby the IPCE value can reach 45% at 0 V vs Ag/AgCl, as demonstrated in Figure 4c

Encapsulation of nanoparticles into single-crystal ZnO nanorods and microrods

• Jinzhang Liu,
• Marco Notarianni,
• Llew Rintoul and
• Nunzio Motta

Beilstein J. Nanotechnol. 2014, 5, 485–493, doi:10.3762/bjnano.5.56

• sufficient end-facet reflectivity and photon confinement in a volume of just a few cubic wavelengths of material. Since the first report of a ZnO nanowire laser, much effort has been placed in nanophotonic research based on small-sized semiconducting nanocrystals with 1D or 2D structures. To study the photon

Tensile properties of a boron/nitrogen-doped carbon nanotube–graphene hybrid structure

• Kang Xia,
• Haifei Zhan,
• Ye Wei and
• Yuantong Gu

Beilstein J. Nanotechnol. 2014, 5, 329–336, doi:10.3762/bjnano.5.37

• previous work on metal nanowires [35] the location of necking is highly related to the strain rate, which could be predicted by the longitudinal wave propagation equation. However, the difference to a nanowire is that the hybrid structure is intrinsically inhomogeneous. Such an inhomogeneity is believed to

Thermal stability and reduction of iron oxide nanowires at moderate temperatures

• Annalisa Paolone,
• Marco Angelucci,
• Stefania Panero,
• Maria Grazia Betti and
• Carlo Mariani

Beilstein J. Nanotechnol. 2014, 5, 323–328, doi:10.3762/bjnano.5.36

• solution, deposited onto Si and Cu substrates, and dried in vacuum before analysis. Results and Discussion TGA measurements were performed both on the as-produced nanowire sample (sample 1) and on a nanowire specimen heated in vacuum (p < 10−4 mbar) for 24 h at 350 K (sample 2), in order to clean the

• , which reaches a value of Δm/m ≈ −0.03 around T1 = 470 K and increases further with higher temperatures. Correspondingly, the mass spectrometer detects a high value of the oxygen signal, which decreases with increasing temperatures. In the case of the nanowire specimen with a cleaned surface (sample 2

• signal of the mass spectrometer for m/z = 32 (left) and of the total mass variation Δm/m (right), of the as-produced nanowire sample (red lines, sample 1) and of the nanowire specimen after a thermal treatment (TT) at 350 K for 24 h in vacuum (blue lines, sample 2). Infrared spectrum (normalized

Modeling and optimization of atomic layer deposition processes on vertically aligned carbon nanotubes

• Nuri Yazdani,
• Vipin Chawla,
• Eve Edwards,
• Vanessa Wood,
• Hyung Gyu Park and
• Ivo Utke

Beilstein J. Nanotechnol. 2014, 5, 234–244, doi:10.3762/bjnano.5.25

• coatings of VACNT arrays. However, the approach can be applied to predict film conformality as a function of depth for any porous topology, including nanopores and nanowire arrays. Keywords: atomic layer deposition; vertically aligned carbon nanotubes; continuum diffusion model; conformal coating

Template based precursor route for the synthesis of CuInSe₂ nanorod arrays for potential solar cell applications

• Mikhail Pashchanka,
• Jonas Bang,
• Niklas S. A. Gora,
• Ildiko Balog,
• Rudolf C. Hoffmann and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2013, 4, 868–874, doi:10.3762/bjnano.4.98

• unique ability for independent adjustment of light absorption (by nanowire length) and charge separation (by nanowire diameter). Nanowire-based photovoltaic layers will allow the fabrication of low-cost small size energy devices with economical use of materials. Very recently, Schoen et al. reported the

• VLS synthesis of CuInSe2 nanowires (by Cu impregnation of In2Se3 nanowires) and the construction of a single-nanowire CIS/CdS core–shell device [4]. However, the authors estimated the efficiency of their solar cell to be below 1%, and the construction of a larger scale device with this approach still

A highly pH-sensitive nanowire field-effect transistor based on silicon on insulator

• Denis E. Presnov,
• Sergey V. Amitonov,
• Pavel A. Krutitskii,
• Valentina V. Kolybasova,
• Igor A. Devyatov,
• Vladimir A. Krupenin and
• Igor I. Soloviev

Beilstein J. Nanotechnol. 2013, 4, 330–335, doi:10.3762/bjnano.4.38

• , Moscow 119991, Russia Keldysh Institute of Applied Mathematics, Moscow 125047, Russia 10.3762/bjnano.4.38 Abstract Background: An experimental and theoretical study of a silicon-nanowire field-effect transistor made of silicon on insulator by CMOS-compatible methods is presented. Results: A maximum

• approach does not yield to the one of sensors built in bottom-up approaches. This provides a good background for the development of CMOS-compatible probes with primary signal processing on-chip. Keywords: charge/field sensor; field-effect transistor; nanowire; pH sensor; silicon-on-insulator

• ; Introduction Over the past decade experimental and theoretical studies of semiconductor nanowire field-effect transistors (NW FET) made of silicon on insulator (SOI) have been of great interest to researchers. The large surface-to-volume ratio of the nanowire allows one to create extremely sensitive charge

High-resolution electrical and chemical characterization of nm-scale organic and inorganic devices

• Pierre Eyben

Beilstein J. Nanotechnol. 2013, 4, 318–319, doi:10.3762/bjnano.4.35

• FETs, nanowire T-FETs, etc.) are being progressively introduced. These new materials are mainly introduced due to their increased mobility (to boost the processing speed of the devices), and the new architectures are required to reduce the junction leakage (and hence reduce the power consumption

Characterization and properties of micro- and nanowires of controlled size, composition, and geometry fabricated by electrodeposition and ion-track technology

• Maria Eugenia Toimil-Molares

Beilstein J. Nanotechnol. 2012, 3, 860–883, doi:10.3762/bjnano.3.97

• , including investigations on electrical resistivity, surface plasmon resonances, and thermal instability. Keywords: electrodeposition; etched ion-track membrane; finite-size effects; heavy ion irradiation; nanowire; radiation-induced nanostructures; Introduction During the past decade, nanowires have

• crystallinity of the nanostructures [7][8][9]. The investigation of size effects requires methods to synthesize nanowires under controlled conditions and with tailored characteristics. Moreover, to characterize physical and chemical properties at the single-nanowire level requires appropriate techniques. In the

• in the fabrication of etched ion-track membranes and electrodeposition of nanowires. Section 2 includes results on the compositional and crystallographic characterization of nanowires of various materials including metals, semimetals and semiconductors. The different nanowire morphologies attained by