Micro- and nano-surface structures based on vapor-deposited polymers

• Hsien-Yeh Chen

Beilstein J. Nanotechnol. 2017, 8, 1366–1374, doi:10.3762/bjnano.8.138

• cell pluripotency against mouse embryonic stem cells [72]. A plasma-polymerized surface with gradient amino functionality was demonstrated to generate density gradients of individual gold (Au) and silver (Ag) nanoparticles on the surfaces [73]. Poly(p-xylylene) surfaces with continuously and counter

Surface-enhanced Raman spectroscopy of cell lysates mixed with silver nanoparticles for tumor classification

• Mohamed Hassoun,
• Iwan W.Schie,
• Tatiana Tolstik,
• Sarmiza E. Stanca,
• Christoph Krafft and
• Juergen Popp

Beilstein J. Nanotechnol. 2017, 8, 1183–1190, doi:10.3762/bjnano.8.120

• absorption band of silver (Ag) nanoparticles corresponds to the maximum of the plasmon resonance which is near 415 nm (Figure 1a). Shifting the plasmon resonance of our nanoparticles to the near-IR spectral region was achieved by aggregation using potassium chloride (KCl). When nanoparticles aggregate, they

• become electronically coupled, which results in a change of the surface plasmon resonance compared to individual particles. Figure 1b shows the effect of adding KCl to Ag nanoparticles on the optical absorption characteristics. The aggregated nanoparticles have a broad absorption band that allowed for

• SERS measurements with an excitation laser at 785 nm. The size and shape of Ag nanoparticles were also analyzed by electron microscopy. Transmission electron microscopy (TEM) images and scanning electron microscopy (SEM) images of silver nanoparticles are compared in Figure 2a and b. The average size

Assembly of metallic nanoparticle arrays on glass via nanoimprinting and thin-film dewetting

• Sun-Kyu Lee,
• Sori Hwang,
• Yoon-Kee Kim and
• Yong-Jun Oh

Beilstein J. Nanotechnol. 2017, 8, 1049–1055, doi:10.3762/bjnano.8.106

• nanoparticles deposited on glass for various optical or photonic devices [24][25]. Well-ordered particle arrays on a glass substrate can change its optical response or absorbance spectra [26][27][28][29][30]. This article aims to demonstrate a method for sequentially fabricating arrays of Au and Ag

• nanoparticles on glass substrates using NIL with transparent MTEOS film and dewetting techniques that can be applied for the photonic devices with sufficient structural integrity. A master mold of square arrays of inverted pyramidal pits with a period of 200 nm was made from (100) silicon wafers with a 40 nm

Needs and challenges for assessing the environmental impacts of engineered nanomaterials (ENMs)

• Michelle Romero-Franco,
• Hilary A. Godwin,
• Muhammad Bilal and
• Yoram Cohen

Beilstein J. Nanotechnol. 2017, 8, 989–1014, doi:10.3762/bjnano.8.101

• easily aggregated, of providing qualitative metrics for ENM ranking (e.g., “most-least” favorable) [32]. The SMAA-TRI approach has been demonstrated for ranking of C60, multi-walled carbon nanotubes (MWCNTs), CdSe, Ag nanoparticles (NP), and Al NP according to the following scales: size (quantitative

Surface-enhanced infrared absorption studies towards a new optical biosensor

• Lothar Leidner,
• Julia Stäb,
• Jennifer T. Adam and
• Günter Gauglitz

Beilstein J. Nanotechnol. 2016, 7, 1736–1742, doi:10.3762/bjnano.7.166

• intensity scattered from the water cover into the direction of the sensor will be negligible. As a consequence, there is only a negligible contribution of water absorption in the reflected signal. In a next step an aqueous solution of 50 nm, stabilized, Ag nanoparticles is added to the water. A portion of

• finding is the shift of the water absorption peak maximum in the presence of Ag nanoparticles in comparison to spectra of liquid water. In our measurements we have a peak maximum at about 3420 cm−1 for pure water in the absence of nanoparticles, which is in good agreement with published values. After

• addition of Ag nanoparticles, there is a shift of the absorption maximum to 3260 cm−1. The absorption features converge to the absorption spectra of ice (see Figure 3). Looking at the spectra of Mizaikoff et al. [13], there seems to be a similar shift of the vibration spectrum to lower wavenumbers. However

Localized surface plasmons in structures with linear Au nanoantennas on a SiO₂/Si surface

• Ilya A. Milekhin,
• Sergei A. Kuznetsov,
• Ekaterina E. Rodyakina,
• Alexander G. Milekhin,
• Alexander V. Latyshev and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2016, 7, 1519–1526, doi:10.3762/bjnano.7.145

• phonon mode at 1230 cm−1 was investigated [10]. Very recently, G. Cacciato et al. [33] have observed plasmon–phonon modes in TiO2 films with embedded Ag nanoparticles due to the coupling of longitudinal optical (LO) phonons in TiO2 with free carriers present in the vicinity of Ag nanoparticles. It should

Electric field induced structural colour tuning of a silver/titanium dioxide nanoparticle one-dimensional photonic crystal

• Eduardo Aluicio-Sarduy,
• Simone Callegari,
• Diana Gisell Figueroa del Valle,
• Andrea Desii,
• Ilka Kriegel and
• Francesco Scotognella

Beilstein J. Nanotechnol. 2016, 7, 1404–1410, doi:10.3762/bjnano.7.131

• layers have a volume of (60 × 10−9 m × 5) × 0.015 m × 0.015 m, and that the diameter of the Ag nanoparticles is about 50 nm, we could estimate an increase of about 105 charges per particle. We remark here that this discussion just gives a rough estimate of the required number of charges added to each

Fast diffusion of silver in TiO₂ nanotube arrays

• Wanggang Zhang,
• Yiming Liu,
• Diaoyu Zhou,
• Hui Wang,
• Wei Liang and
• Fuqian Yang

Beilstein J. Nanotechnol. 2016, 7, 1129–1140, doi:10.3762/bjnano.7.105

• , as shown in Figure 5b. There are Ag nanoparticles present on the outmost surface of the TiO2 nanotubes. The Ag nanofilm became irregular due to the migration of Ag through the TiO2 nanotube arrays and dewetting of the Ag nanofilm, and the topology of TiO2 nanotubes become visible (see Figure S2b in

• Supporting Information File 1). The increase of the temperature to 400 °C for the heat treatment caused a significant amount of Ag to migrate through the TiO2 nanotube arrays, as shown in Figure 5c, leading to the formation of Ag nanoparticles. There was a layer of Ag over the TiO2 nanotubes. Ag

• nanoparticles scattered around the propagation front, likely representing the nucleation and growth of Ag nanoparticles induced by the migration/diffusion of Ag during the heat treatment. For the segment of the TiO2 nanotubes not covered by the Ag layer and Ag nanoparticles, the outmost surface remained

Controlled graphene oxide assembly on silver nanocube monolayers for SERS detection: dependence on nanocube packing procedure

• Martina Banchelli,
• Bruno Tiribilli,
• Roberto Pini,
• Luigi Dei,
• Paolo Matteini and
• Gabriella Caminati

Beilstein J. Nanotechnol. 2016, 7, 9–21, doi:10.3762/bjnano.7.2

• -functionalized Ag nanoparticles [19], detailed information on the GO coating step is not systematically studied and validated. Since the Raman scattering enhancement is strictly dependent on the geometry of the system at the nanoscale, controlling how GO affects the distribution of the AgNCs arrays is a key-step

• behaviour of an extensively studied model probe such as adenine adsorbed on the resulting arrays. Preliminary results show that higher SERS intensities are detected from the GO/AgNCs hybrid nanostructures as compared to pure Ag nanoparticles for both nanoparticle packing procedures. Interestingly, we found

• Langmuir–Blodgett technique The dispersion of silver nanocubes was spread at the water–air interface from a chloroform solution in a Langmuir trough to fabricate a monolayer of Ag nanoparticles. In agreement with the pioneering work by El-Sayed [37], we found that AgNCs are easily spread at the water–air

NanoE-Tox: New and in-depth database concerning ecotoxicity of nanomaterials

• Katre Juganson,
• Angela Ivask,
• Irina Blinova,
• Monika Mortimer and
• Anne Kahru

Beilstein J. Nanotechnol. 2015, 6, 1788–1804, doi:10.3762/bjnano.6.183

• Information File 1) revealed that the majority of the papers concerned the applications of carbon nanotubes (36,609 papers, 40%), followed by Ag nanoparticles (NPs; 16,970, 19%), TiO2 NPs (11,802, 13%), and iron oxide NPs (10,479, 11%) while the most common fields of application were sensors (28,027 papers

Synthesis, characterization and in vitro effects of 7 nm alloyed silver–gold nanoparticles

• Simon Ristig,
• Svitlana Chernousova,
• Wolfgang Meyer-Zaika and
• Matthias Epple

Beilstein J. Nanotechnol. 2015, 6, 1212–1220, doi:10.3762/bjnano.6.124

• determined by DCS or TEM (see [30][34] about this systematic difference), but independent of the particle composition. Only the pure Ag nanoparticles had a much larger hydrodynamic radius of 22 nm. Analysis of the electrophoretic mobility yielded negative zeta potentials, indicating a reasonable

Improved optical limiting performance of laser-ablation-generated metal nanoparticles due to silica-microsphere-induced local field enhancement

• Zheren Du,
• Lianwei Chen,
• Tsung-Sheng Kao,
• Mengxue Wu and
• Minghui Hong

Beilstein J. Nanotechnol. 2015, 6, 1199–1204, doi:10.3762/bjnano.6.122

• the colloidal solution. The silver nanoparticle diameters range from 20 to 500 nm with maximum at 80 nm. It can be seen that a few Ag nanoparticles have a relatively larger diameter in the range of a few hundred nanometers. Comparing these two types of nanoparticles, the Au nanoparticles have a

• absorbed laser energy. Hence, the size of the laser-generated Ag nanoparticles is larger. Au and Ag have different physical properties, such as the absorption spectrum of the laser light, melting point, boiling point and thermal conductivity, which all can contribute to the size difference. The laser

Electromagnetic enhancement of ordered silver nanorod arrays evaluated by discrete dipole approximation

• Guoke Wei,
• Jinliang Wang and
• Yu Chen

Beilstein J. Nanotechnol. 2015, 6, 686–696, doi:10.3762/bjnano.6.69

• shoulder at around 550 nm. These resonances can be assigned as dipole (550 nm) and quadrupole (360 nm) plasmon modes, respectively, as found in Ag nanoparticles of large sizes [20]. In the case of p-polarized excitation, the extinction spectra has a broad band ranging from 320 to 800 nm, with three

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

• been demonstrated with Pd–Ag nanoparticles on graphene sheets, however, they were not “rolled” into CNTs [107]. Both vapour phase filling and in situ filling techniques have been combined to produce MWCNTs that are doped with various other elements, such as phosphorous and nitrogen, which can then

Raman spectroscopy as a tool to investigate the structure and electronic properties of carbon-atom wires

• Alberto Milani,
• Matteo Tommasini,
• Valeria Russo,
• Andrea Li Bassi,
• Andrea Lucotti,
• Franco Cataldo and
• Carlo S. Casari

Beilstein J. Nanotechnol. 2015, 6, 480–491, doi:10.3762/bjnano.6.49

• direction so far. We demonstrated that H-terminated polyynes could be embedded in a solid assembly of Ag nanoparticles resulting in a sample which is stable for several weeks at room temperature under ambient conditions [60]. Hayashi and co-workers showed that it is possible to produce a polymeric composite

• (i.e., poly(vinyl alcohol)) containing polyynes stabilized by Ag nanoparticles [61]. Due to their high stability, polyynes in liquids (up to 14–16 carbon atoms) can now be synthesized even in the form of size-selected samples [5][62][63] and with well-defined end groups [54]. Solid-state samples have

Inorganic Janus particles for biomedical applications

• Isabel Schick,
• Steffen Lorenz,
• Dominik Gehrig,
• Stefan Tenzer,
• Wiebke Storck,
• Karl Fischer,
• Dennis Strand,
• Frédéric Laquai and
• Wolfgang Tremel

Beilstein J. Nanotechnol. 2014, 5, 2346–2362, doi:10.3762/bjnano.5.244

• conjugation to Ag nanoparticles when combined to form Ag@Fe3O4 dumbbell-like hetero-nanoparticles [47]. Moreover, plasmonic photocatalysts combine two prominent features: a Schottky junction enhancing charge separation and surface plasmon resonance, which is responsible for strong absorption of visible light

Current state of laser synthesis of metal and alloy nanoparticles as ligand-free reference materials for nano-toxicological assays

• Christoph Rehbock,
• Jurij Jakobi,
• Lisa Gamrad,
• Selina van der Meer,
• Daniela Tiedemann,
• Ulrike Taylor,
• Wilfried Kues,
• Detlef Rath and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2014, 5, 1523–1541, doi:10.3762/bjnano.5.165

• dominating mechanism involved in nanotoxicity of these materials [82][83]. Next to the above specified examples on AuAg alloys [35][148] the applicability of ligand-free Au and Ag nanoparticles in reproduction biology was demonstrated. This includes effects on spermatozoa [147] as well as on embryo

• [156], TiO2, ZnO [157], Ni, NiTi, NiFe, Ti [11] and MoS2 [158] on the viability of mammalian cell lines were studied. Furthermore, some studies addressed antimicrobial effects of Ni [159] and Ag nanoparticles [160][161]. Additionally, some authors reported on the application of laser-fabricated CuO

Microstructural and plasmonic modifications in Ag–TiO₂ and Au–TiO₂ nanocomposites through ion beam irradiation

• Venkata Sai Kiran Chakravadhanula,
• Yogendra Kumar Mishra,
• Venkata Girish Kotnur,
• Devesh Kumar Avasthi,
• Thomas Strunskus,
• Vladimir Zaporotchenko,
• Dietmar Fink,
• Lorenz Kienle and
• Franz Faupel

Beilstein J. Nanotechnol. 2014, 5, 1419–1431, doi:10.3762/bjnano.5.154

• bright-field TEM images are shown in Figure 2. A closer look at all TEM images in Figure 2 reveals the growth of smaller as well as larger Ag nanoparticles during co-sputtering process and the average diameter of Ag nanoparticles increases with increasing Ag metal volume fraction. In fact a deeper look

• ]. The dark and bright contrasts in the TEM image correspond to Ag nanoparticles and TiO2 matrix, respectively. Detailed investigations on the particle size distribution of the Ag nanoparticles embedded in a TiO2 matrix have been performed by 3D-tomography studies [39][40]. Tomography results have

• confirmed the bimodal distribution of Ag nanoparticles with the presence of larger nanoparticles on top of the surface and smaller nanoparticles embedded inside the matrix. To investigate the effect of ion irradiation on metal–TiO2 nanocomposites, the deposited Au–TiO2 and Ag–TiO2 nanocomposite films (both

Effects of the preparation method on the structure and the visible-light photocatalytic activity of Ag₂CrO₄

• Difa Xu,
• Shaowen Cao,
• Jinfeng Zhang,
• Bei Cheng and
• Jiaguo Yu

Beilstein J. Nanotechnol. 2014, 5, 658–666, doi:10.3762/bjnano.5.77

• photocatalytic reaction, the corresponding SEM and TEM images, XRD pattern, and UV–vis diffuse reflectance spectrum were collected. Figure 9a and Figure 9b show that the overall morphology and average particle size of Ag2CrO4 were not changed significantly. However, some homogenously distributed Ag nanoparticles

Enhanced photocatalytic activity of Ag–ZnO hybrid plasmonic nanostructures prepared by a facile wet chemical method

• Sini Kuriakose,
• Vandana Choudhary,
• Biswarup Satpati and
• Satyabrata Mohapatra

Beilstein J. Nanotechnol. 2014, 5, 639–650, doi:10.3762/bjnano.5.75

• ) have been investigated. Increase in citrate concentration has been found to result in the formation of nanodisk-like structures, due to citrate-assisted oriented attachment of ZnO nanoparticles. The decoration of ZnO nanostructures with Ag nanoparticles resulted in a significant enhancement of the

• photocatalytic degradation of rhodamine B (RhB) and showed that the degradation of RhB over pure Ag nanowires was negligible as compared to ZnO, the degradation efficiency of which further was increased due to the decoration with Ag nanoparticles. Deng et al. [19] fabricated Ag nanoparticles decorated ZnO

• peaks in the diffraction patterns clearly indicates the formation of crystalline Ag nanoparticles by photoreduction onto ZnO nanostructures. No extra peaks related to any impurity or silver oxides were observed, which confirms that the as-synthesized products are pure wurtzite ZnO and Ag–ZnO hybrid

Cytotoxic and proinflammatory effects of PVP-coated silver nanoparticles after intratracheal instillation in rats

• Nadine Haberl,
• Stephanie Hirn,
• Alexander Wenk,
• Jörg Diendorf,
• Matthias Epple,
• Blair D. Johnston,
• Fritz Krombach,
• Wolfgang G. Kreyling and
• Carsten Schleh

Beilstein J. Nanotechnol. 2013, 4, 933–940, doi:10.3762/bjnano.4.105

• Bavaria, Approval No.55.2-1-54-2531-26-10) and by the Institutional Animal Care and Use Committee of the Helmholtz Center Munich. PVP-coated Ag nanoparticles (PVP-AgNP) PVP-AgNP were prepared by reduction with glucose in the presence of PVP as described before [37][45]. The silver nanoparticles were

Photocatalytic antibacterial performance of TiO₂ and Ag-doped TiO₂ against S. aureus. P. aeruginosa and E. coli

• Kiran Gupta,
• R. P. Singh,
• Ashutosh Pandey and
• Anjana Pandey

Beilstein J. Nanotechnol. 2013, 4, 345–351, doi:10.3762/bjnano.4.40

• blocking of respiration and cell death of the bacteria [10]. Another remarkable mechanism of the antimicrobial activity of Ag nanoparticles is related to the formation of free radicals and consequent free-radical-induced oxidative damage of the cell membranes of bacteria [11][12]. But the same result was

Plasticity of Cu nanoparticles: Dislocation-dendrite-induced strain hardening and a limit for displacive plasticity

• Antti Tolvanen and
• Karsten Albe

Beilstein J. Nanotechnol. 2013, 4, 173–179, doi:10.3762/bjnano.4.17

• threshold pressure, depending on the material properties, is reached. In their pioneering work, Sun et al. [7] studied the extrusion of Ag nanoparticles experimentally and attributed the plastic flow to dislocation activity, based on a combination of simulation results on Pt showing traces of dislocation

Paper modified with ZnO nanorods – antimicrobial studies

• Mayuree Jaisai,
• Sunandan Baruah and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2012, 3, 684–691, doi:10.3762/bjnano.3.78

• indexed planes confirm the wurtzite structure of ZnO (Figure 7b). The addition of functionalities to paper should not have a detrimental effect on its inherent properties, such as brightness, ink-retention capability, etc. Addition of Ag nanoparticles gives a yellowish tinge to the paper thereby affecting

• , fungal infections in books are treated by using chemical methods. Libraries need to be maintained at a temperature and relative humidity that are not conducive to fungal growth [1]. Paper with antimicrobial properties could be an answer to the problems faced by libraries and health centers. Silver (Ag

• ) nanoparticles embedded into a paper matrix have been reported as exhibiting antibacterial properties [4]. Wallpaper prepared by using zinc oxide nanoparticle (~20 nm) coatings has been reported to render antibacterial surfaces that inhibit growth of bacteria such as Escherichia coli (E. coli) [5]. An increase

Ultraviolet photodetection of flexible ZnO nanowire sheets in polydimethylsiloxane polymer

• Jinzhang Liu,
• Nunzio Motta and
• Soonil Lee

Beilstein J. Nanotechnol. 2012, 3, 353–359, doi:10.3762/bjnano.3.41

• PDMS would slowly spread out of the agglomeration of Ag nanoparticles and infiltrate the nanowire film due to capillarity. Figure 3a shows the current–voltage (I–V) curves of the device in PDMS, measured under UV-light illumination (312 nm, 30 mW·cm−2) and in the dark. The I–V curves of two other

• vacuum deposited Ag also shows nearly ohmic contact on ZnO (Figure 3b). However, for the contact of Ag paste on ZnO, the I–V curves measured under UV illumination and in the dark show rectifying features. Presumably, the Ag nanoparticles that we used to make the Ag–PDMS paste were spontaneously oxidized

• due to ageing. The surface Ag2O layer, a narrow bandgap semiconductor, added an extra barrier for electrons flowing between Ag nanoparticles and ZnO nanowires, resulting in the nonlinear I–V curves in Figure 3a. The I–V curve of the device in PDMS measured in the dark, plotted in the insert in Figure