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

• -Aldrich, aluminum nitrate nanohydrate (Al(NO3)3·9H2O) and tetraethoxysilane (TEOS) were used for the Al and Si sources, respectively, both purchased from Shantou Chemical Corp., China. All other chemicals were purchased from Tianjin Chemical Company (Tianjin, China). All chemicals were analytically pure

Oxygen-plasma-modified biomimetic nanofibrous scaffolds for enhanced compatibility of cardiovascular implants

• Anna Maria Pappa,
• Varvara Karagkiozaki,
• Silke Krol,
• Spyros Kassavetis,
• Dimitris Konstantinou,
• Charalampos Pitsalidis,
• Lazaros Tzounis,
• Nikos Pliatsikas and
• Stergios Logothetidis

Beilstein J. Nanotechnol. 2015, 6, 254–262, doi:10.3762/bjnano.6.24

• present reference study were mouse fibroblasts (L929). In Figure 4a and Figure 4b, the MTT results of the cytotoxicity levels of all the samples (i.e., control group, aluminum foil, untreated scaffold and mildly treated scaffold) in direct contact with the L929s are given. According to the findings, all

• were fabricated by electrospinning through the electrostatic spray deposition (ESD) method, (Esprayer ES-2000S, Fuence, Japan) onto aluminum foil and glass substrates. For the fabrication of the polymeric solutions, a solution of PCL was prepared with a total concentration of 20–25 wt % in a solvent

Increasing throughput of AFM-based single cell adhesion measurements through multisubstrate surfaces

• Miao Yu,
• Nico Strohmeyer,
• Jinghe Wang,
• Daniel J. Müller and
• Jonne Helenius

Beilstein J. Nanotechnol. 2015, 6, 157–166, doi:10.3762/bjnano.6.15

• features exceeding 40 nm in height. These are replications of imperfections in the aluminum mold. Although the sensitivity of AFM imaging is high enough to detect protein coatings, the overall roughness of the surface conceals the thin protein layers, and, thus, detection of the presence of a scratched

• adhesive substrates to be measured. The masks were cast in aluminum molds, which can be made in most mechanical workshops. We characterized the masks with regard to surface topography, protein coating ability and applicability for light microscopy. While the PDMS surface was very rough compared to the

• for nine masks was used (Figure 2A). For the mold, 150 µm-deep cavities were machined in an 8 mm-thick aluminum plate (Figure 2B), which was then anodized to harden its surface. To reduce adhesion of PDMS to the mold, the mold was silanized overnight with 200 µL of perfluorooctyltrichlorosilane in a

Synthesis of boron nitride nanotubes and their applications

• Saban Kalay,
• Zehra Yilmaz,
• Ozlem Sen,
• Melis Emanet,
• Emine Kazanc and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9

• mechanism is called vapor–liquid–solid (VLS). The high yield of BNNTs was observed as a white powder in the inner wall of the aluminum boat and on the substrate. Note that for the BOCVD mechanism to occur, variation in the types of catalysts, boron compounds and nitrogen-containing gases should be used. The

• . synthesized BNNTs by means of microwave plasma at a temperature lower than 520 °C [40]. In this technique, a 6–100 nm pore size, aluminum oxide template was used along with microwave plasma. The BNNTs were grown on the surface of this template in the presence of B2H6/Ar and NH3/N2 at 10−4 Pa pressure at 520

• °C. The diameter of the synthesized BNNTs was the same as the pore size diameter of the aluminum oxide template. The BNNTs were synthesized in a stainless steel autoclave at 380 °C from amorphous boron, NaN3, and CH3CN for 14 h. The obtained product was washed with ethanol, dried and a 5% BNNTs yield

Exploring plasmonic coupling in hole-cap arrays

• Thomas M. Schmidt,
• Maj Frederiksen,
• Vladimir Bochenkov and
• Duncan S. Sutherland

Beilstein J. Nanotechnol. 2015, 6, 1–10, doi:10.3762/bjnano.6.1

• 200,000–350,000), PSS (poly(sodium 4-styrenesulfonate)) (Mw 70,000) and toluene were obtained from Aldrich Denmark. Poly aluminum chlorohydrate (PAX XL 60) was obtained from Kemwater Denmark. Round glass cover slides of soda-lime glass # 3 from Menzel–Gläser (d = 24 mm) Germany. Silicon wafers (thickness

Low cost, p-ZnO/n-Si, rectifying, nano heterojunction diode: Fabrication and electrical characterization

• Vinay Kabra,
• Lubna Aamir and
• M. M. Malik

Beilstein J. Nanotechnol. 2014, 5, 2216–2221, doi:10.3762/bjnano.5.230

• ) was mixed with a 25% aqueous ammonia solution and aluminum chloride as nitrogen and aluminum sources, respectively. These were mixed in the atomic ratio of Zn:N:Al to 1:0.06:0.03 at room temperature under constant stirring. A freshly prepared tetramethylammonium hydroxide (TMAH) solution was added to

Imaging the intracellular degradation of biodegradable polymer nanoparticles

• Anne-Kathrin Barthel,
• Martin Dass,
• Melanie Dröge,
• Jens-Michael Cramer,
• Daniela Baumann,
• Markus Urban,
• Katharina Landfester,
• Volker Mailänder and
• Ingo Lieberwirth

Beilstein J. Nanotechnol. 2014, 5, 1905–1917, doi:10.3762/bjnano.5.201

• , the cells were detached by trypsin and newly seeded out. At the specified residence times, the sapphire disks were removed from the wells and dipped into 1-hexadecane to remove the remaining medium. The disks were covered with aluminum disks to prevent squeezing of the cells and the sandwich was

• injected into a high pressure freezing device (Wohlwend, Switzerland). The frozen sandwich was stored in liquid N2. The aluminum cover was removed in a liquid N2 environment and the sapphire disk was transferred into anhydrous acetone at −90 °C, (Merck, Germany) containing 4% aqueous osmium tetroxide (Roth

Magnesium batteries: Current state of the art, issues and future perspectives

• Rana Mohtadi and
• Fuminori Mizuno

Beilstein J. Nanotechnol. 2014, 5, 1291–1311, doi:10.3762/bjnano.5.143

• provide higher energy densities without compromising the safety of the battery. For example metals such as magnesium and aluminum were proposed [1][7]. Magnesium metal has been attracting an increased attention as it possesses higher volumetric capacities than lithium metal, i.e., 3832 mAh cm−3 vs 2061

• . Substitution of the boron with aluminum or the hydrogen in the aromatic rings with fluoride (as was demonstrated recently [8]) was proposed to help enhance its oxidative stability. Note that a recent report by Muldoon et al. [19] confirmed the low solubility of Mg(BPh4)2, Mg(BPh3Bu)2 and found that Mg(BPh3Bu)2

• Grignard reagent with aluminum-based Lewis acids such as AlCl3−nRn; where R was an alkyl [20]. Their concept was to strengthen the Mg–C bond in the Grignard reagent, through increasing its ionic character, by adding an electron withdrawing Lewis acid. The optimized compositions of the organohalo-aluminate

Review of nanostructured devices for thermoelectric applications

• Giovanni Pennelli

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

• arrays can also be produced by the simpler and cheaper innovative pattering technique nanosphere lithography [120][121]; The evaporation of Ag or Au through porous aluminum oxide membranes[122][123][124] gives a periodic and almost regular pattern for vertically etched nanowire arrays. A thin evaporation

Nanoporous composites prepared by a combination of SBA-15 with Mg–Al mixed oxides. Water vapor sorption properties

• Amaury Pérez-Verdejo,
• Alvaro Sampieri,
• Heriberto Pfeiffer,
• Mayra Ruiz-Reyes,
• Juana-Deisy Santamaría and
• Geolar Fetter

Beilstein J. Nanotechnol. 2014, 5, 1226–1234, doi:10.3762/bjnano.5.136

• basic pH, as SiO2 is not formed. Furthermore, during calcination, the nanocasting of Mg–Al species can occur on the mesoporous surface of the SBA-15 [9]. Indeed, the Mg–Al hydrotalcite becomes a magnesium–aluminum mixed oxide (Mg–Al–O) nanoparticles with thermal treatment and the average wall thickness

• composite presents a Mg/Al molar ratio of 1.40, which is lower than that of the nominal composition. Thus, the aluminum content is higher than the magnesium amount. These results are also in agreement with the SEM-EDX mapping images shown in Figure 4. Furthermore, these images confirm that Al and Mg oxides

Organic and inorganic–organic thin film structures by molecular layer deposition: A review

• Pia Sundberg and
• Maarit Karppinen

Beilstein J. Nanotechnol. 2014, 5, 1104–1136, doi:10.3762/bjnano.5.123

• precursor (Table 11). When metal precursors are combined with alcohols or phenols, the resultant material is often called “metalcone” [27]. Most of the research has been focused on the aluminum-based alucones [12][13][15][16][38][39][81][82][83][84][85][86][87][88][89][90][91][92][93][94][95][96][97], but

Characterization and photocatalytic study of tantalum oxide nanoparticles prepared by the hydrolysis of tantalum oxo-ethoxide Ta₈(μ₃-O)₂(μ-O)₈(μ-OEt)₆(OEt)₁₄

• Subia Ambreen,
• N D Pandey,
• Peter Mayer and
• Ashutosh Pandey

Beilstein J. Nanotechnol. 2014, 5, 1082–1090, doi:10.3762/bjnano.5.121

• , fused calcium chloride and aluminum isopropoxide, then it was passed into the distilled water through a tube with a diameter of 7 mm. 1H NMR spectra were recorded in C6D6 on a Bruker Biospin ARX spectrometer with TMS as internal reference. TGA/DTA/DSC was recorded by using a Diamond TG/DTAN instrument

Impact of thermal frequency drift on highest precision force microscopy using quartz-based force sensors at low temperatures

• Florian Pielmeier,
• Daniel Meuer,
• Daniel Schmid,
• Christoph Strunk and
• Franz J. Giessibl

Beilstein J. Nanotechnol. 2014, 5, 407–412, doi:10.3762/bjnano.5.48

• with non-conductive epoxy to an aluminum oxide substrate which is commonly used for our qPlus sensors, the electrodes are then contacted with conductive epoxy. For the low temperature measurements the substrates where glued again with non-conductive epoxy onto a piece of copper. The copper piece serves

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

• dioxide and aluminum oxide. To synthesize our VACNTs, a 3-nm-thick catalyst layer of iron on top of a 20-nm-thick layer of aluminum is deposited through electron beam evaporation onto a silicon wafer. The VACNTs are then grown by chemical vapor deposition in a cold-wall CVD system. The catalyst-covered

• precursor mixture of titanium isopropoxide (Ti{OCH(CH3)2}4, TTIP) heated to 90 °C and water vapor at 40 °C. One ALD cycle consists of a 5 s long pulse and 40 s long hold of TTIP, followed by a 0.5 s long pulse and 40 s long hold of water vapor, with 60 s long Ar purges in between the two pulses. Aluminum

• time (see Equation 18). To experimentally validate the pulse time scaling procedure developed from the model, we perform depositions of aluminum oxide on VACNT samples, during which we attempt to keep the penetration depth of each ALD cycle constant over one hundred cycles. In Figure 6c, the oxide

Charge and spin transport in mesoscopic superconductors

• M. J. Wolf,
• F. Hübler,
• S. Kolenda and
• D. Beckmann

Beilstein J. Nanotechnol. 2014, 5, 180–185, doi:10.3762/bjnano.5.18

• regime [11][12][13]. In contrast, only few experiments on quasiparticle spin transport [14] have been reported, and the subject remains poorly understood. For example, both anomalously short [15] and anomalously long [16] spin relaxation times have been reported in superconducting aluminum. In this paper

• measurement scheme. A central superconducting aluminum wire is contacted by several normal-metal (copper) or ferromagnetic (iron) electrodes attached via thin tunnel barriers. A dc bias voltage Vinj with a small superimposed low-frequency ac excitation is applied to one junction (injector), and the resulting

• indicated in Figure 1. The measurements were carried out in a dilution refrigerator at temperatures down to about 50 mK, and with a magnetic field B applied along the substrate plane parallel to the copper or iron wires. The thickness of the aluminum films was tAl = 12–30 nm, and for the thinnest films

Photovoltaic properties of ZnO nanorods/p-type Si heterojunction structures

• Rafal Pietruszka,
• Bartlomiej S. Witkowski,
• Grzegorz Luka,
• Lukasz Wachnicki,
• Sylwia Gieraltowska,
• Krzysztof Kopalko,
• Eunika Zielony,
• Piotr Bieganski,
• Ewa Placzek-Popko and
• Marek Godlewski

Beilstein J. Nanotechnol. 2014, 5, 173–179, doi:10.3762/bjnano.5.17

• used to store data for a long period of time [21]. In PV structures, ZnO can replace the commonly used indium tin oxide (ITO) as a transparent electrode. Thin films of ZnO doped with aluminum (ZnO:Al, AZO) or gallium (ZnO:Ga, GZO) obtained by various deposition methods, show a resistivity of the order

• nm, a length of approximately 800 nm, and are close to each other. Average sizes of ZnO NRs and ZnO NRs covered ZnO:Al layers are summarized in Table 1. We obtained three distinct types of ZnO nanorods by changing the pH values denoted as sample A, sample B and sample C. ZnO with aluminum atoms (AZO

• aluminum precursor. The growth temperature was 160 °C and the N2 was used as a purging gas. To obtain a high conductivity of the ZnO film, we mixed ALD cycles. We applied 1 cycle TMA + H2O and 24 cycles of DEZ + H2O to obtain a uniform distribution of Al in the layer. The lowest resistivity was achieved

3D-nanoarchitectured Pd/Ni catalysts prepared by atomic layer deposition for the electrooxidation of formic acid

• Loïc Assaud,
• Evans Monyoncho,
• Kristina Pitzschel,
• Anis Allagui,
• Matthieu Petit,
• Margrit Hanbücken,
• Elena A. Baranova and
• Lionel Santinacci

Beilstein J. Nanotechnol. 2014, 5, 162–172, doi:10.3762/bjnano.5.16

• intermediates. High catalytic activities are measured for low masses of Pd coatings that were generated by a low number of ALD cycles, probably because of the cluster size effect, electronic interactions between Pd and Ni, or diffusion effects. Keywords: anodic aluminum oxide; atomic layer deposition (ALD

• aluminum oxide (AAO) has been used as nanostructured support for the Pd catalysts. The AAO membranes are attractive because they exhibit a high specific surface area and the pore diameter and length can be tailored easily [27][28]. In this study, the usual two-step anodization process shown in Figure 1a–e

• nanocatalysts. Experimental The porous alumina structures have been grown on 4 cm wide aluminum discs (Goodfellow, 99.999%) by using the method that is schematically depicted in Figure 1a–e. The aluminum was first electropolished in an alcoholic solution of perchloric acid and successively anodized at a

Surface assembly and nanofabrication of 1,1,1-tris(mercaptomethyl)heptadecane on Au(111) studied with time-lapse atomic force microscopy

• Tian Tian,
• Burapol Singhana,
• Lauren E. Englade-Franklin,
• Xianglin Zhai,
• T. Randall Lee and
• Jayne C. Garno

Beilstein J. Nanotechnol. 2014, 5, 26–35, doi:10.3762/bjnano.5.3

• dried with calcium hydride (CaH2) and distillated before use. Pyridinium chlorochromate (PCC) and lithium aluminum hydride (LiAlH4) were purchased from Alfa Aesar. 1-Octadecanol (ReagentPlus®, 99%), formaldehyde (37 wt % in H2O), trifluoromethanesulfonic anhydride (≥99%), 18-crown-6 (≥99.9%), pyridine

Synthesis and electrochemical performance of Li₂Co_1−xM_xPO₄F (M = Fe, Mn) cathode materials

• Nellie R. Khasanova,
• Oleg A. Drozhzhin,
• Stanislav S. Fedotov,
• Darya A. Storozhilova,
• Rodion V. Panin and
• Evgeny V. Antipov

Beilstein J. Nanotechnol. 2013, 4, 860–867, doi:10.3762/bjnano.4.97

• 1 M LiBF4/TMS to investigate the electrochemical activity of the fluorophosphate materials. LiBF4 salt was chosen instead of LiTFSI, because the last one corrodes the aluminum current collector at high potentials. Preliminarily, the stability of both electrolytes was investigated by cyclic

• experiments, the obtained current values were compared without normalization. Both electrolytes exhibited an electrochemical stability up to 5.5 V (vs Li/Li+) with aluminum as the working electrode (Figure 2a). For the first cycle the current detected at the highest potential did not exceed 0.4 μА, and it

• 3D-Li2MPO4F, positions of Li atoms are denoted. Cyclovoltammetry curves (first cycle) of 1 M LiPF6 in EC/DMC (black) and 1 M LiBF4 in TMS (red) at scan rate of 0.1 mV·s−1. (a) Aluminum electrode, (b) idle electrode consisting of Al2O3/C/PVdF in an 80/10/10 ratio. Powder XRD patterns of Li2CoPO4F/C (a

Synthesis of boron nitride nanotubes from unprocessed colemanite

• Saban Kalay,
• Zehra Yilmaz and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2013, 4, 843–851, doi:10.3762/bjnano.4.95

• ][18][19]. In the template-assisted synthesis, a commonly used method, the BNNTs are synthesized by using CNTs or an aluminum filter as templates [15][17]. The CNTs interact with B2O3 and NH3 gas to replace C atoms with B and N atoms to form tubes which contain C, B and N. Finally, an oxidation process

• , hydrogen storage, and the improvement of the mechanical as well as the chemical durability of polymer composites. Experimental Material and methods Colemanite (Ca2B6O11·5H2O) was a gift from Eti Mine Works General Management (Turkey). Iron (III) oxide, iron (II, III) oxide, aluminum oxide, zinc oxide

Ellipsometry and XPS comparative studies of thermal and plasma enhanced atomic layer deposited Al₂O₃-films

• Jörg Haeberle,
• Karsten Henkel,
• Hassan Gargouri,
• Franziska Naumann,
• Bernd Gruska,
• Michael Arens,
• Massimo Tallarida and
• Dieter Schmeißer

Beilstein J. Nanotechnol. 2013, 4, 732–742, doi:10.3762/bjnano.4.83

• , Germany 10.3762/bjnano.4.83 Abstract We report on results on the preparation of thin (<100 nm) aluminum oxide (Al2O3) films on silicon substrates using thermal atomic layer deposition (T-ALD) and plasma enhanced atomic layer deposition (PE-ALD) in the SENTECH SI ALD LL system. The T-ALD Al2O3 layers were

• °C T-ALD and PE-ALD processes yield films with similar refractive indices and with oxygen to aluminum elemental ratios very close to the stoichiometric value of 1.5. However, in both also fragments of the precursor are integrated into the film. The PE-ALD films show an increased growth rate and lower

• carbon contaminations. Reducing the deposition temperature down to rt leads to a higher content of carbon and CH-species. We also find a decrease of the refractive index and of the oxygen to aluminum elemental ratio as well as an increase of the growth rate whereas the homogeneity of the film growth is

Surface passivation and optical characterization of Al₂O₃/a-SiC_x stacks on c-Si substrates

• Gema López,
• Pablo R. Ortega,
• Cristóbal Voz,
• Isidro Martín,
• Mónica Colina,
• Anna B. Morales,
• Albert Orpella and
• Ramón Alcubilla

Beilstein J. Nanotechnol. 2013, 4, 726–731, doi:10.3762/bjnano.4.82

• study the surface passivation of aluminum oxide/amorphous silicon carbide (Al2O3/a-SiCx) stacks on both p-type and n-type crystalline silicon (c-Si) substrates as well as the optical characterization of these stacks. Al2O3 films of different thicknesses were deposited by thermal atomic layer deposition

• ) was evaluated at a carrier injection level corresponding to 1-sun illumination, which led to values below 10 cm/s. Reflectance values below 2% were measured on textured samples over the wavelength range of 450–1000 nm. Keywords: aluminum oxide (Al2O3); antireflection coating; atomic layer deposition

• ; silicon carbide (SiCx); surface passivation; Introduction Surface passivation has become a relevant issue in high efficiency crystalline silicon (c-Si) solar cells. The importance is even increasing as thinner wafers are used to reduce the cost for photovoltaic applications [1]. Aluminum oxide (Al2O3

Modulation of defect-mediated energy transfer from ZnO nanoparticles for the photocatalytic degradation of bilirubin

• Tanujjal Bora,
• Karthik K. Lakshman,
• Soumik Sarkar,
• Abhinandan Makhal,
• Samim Sardar,
• Samir K. Pal and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2013, 4, 714–725, doi:10.3762/bjnano.4.81

• slowly added to the zinc acetate solution and mixed properly. The glass beaker was then covered tightly with aluminum foil and placed in a pre-heated water bath at 60 °C for 2 hours to hydrolyze. After 2 h, the resultant transparent ZnO nanoparticle colloidal solution was allowed to cool down to room

Preparation of electrochemically active silicon nanotubes in highly ordered arrays

• Tobias Grünzel,
• Young Joo Lee,
• Karsten Kuepper and
• Julien Bachmann

Beilstein J. Nanotechnol. 2013, 4, 655–664, doi:10.3762/bjnano.4.73

• matrix (white) will be prepared by the two-step anodization of aluminum, a procedure which enables the experimentalist to generate templates of ordered cylindrical pores with a tunable period 50 nm ≤ P ≤ 450 nm and a length 0.1 µm ≤ L ≤ 100 µm [10][11]. Subsequently, the functional material will be

• preparation The preparative path devised for making ordered arrays of electrically contacted silicon nanotubes is presented in Figure 2. In the first step (a), a double anodization (electrochemical oxidation of aluminum in a protic solution) is carried out under 40 V in oxalic acid at 7 °C according to the

• standard procedure [11]: after the first anodization, the disordered porous aluminum oxide layer obtained is removed in chromic acid, then the ordered porous layer is obtained by a second anodization in the same conditions. The length of the pores is defined by the duration of this second anodization

Functionalization of vertically aligned carbon nanotubes

• Eloise Van Hooijdonk,
• Carla Bittencourt,
• Rony Snyders and
• Jean-François Colomer

Beilstein J. Nanotechnol. 2013, 4, 129–152, doi:10.3762/bjnano.4.14

• deposited within the pores of nanoporous templates (for example, anodic aluminum oxide (AAO) membranes) allows design of a wide range of nanostructures with particular geometries, including aligned and monodispersed CNTs [40]. After the catalyst preparation, the next step is the synthesis of the VA-CNTs