Controlling surface morphology and sensitivity of granular and porous silver films for surface-enhanced Raman scattering, SERS

• Sherif Okeil and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2018, 9, 2813–2831, doi:10.3762/bjnano.9.263

• ][55][56], and nanotransfer printing, which was used to build stacks of gold nanorods or nanowires [4]. The production of nanoporous metal films or particles through a dealloying process also emerged as an effective tool for the facile formation of a large number of SERS-active hot spots [57][58][59

Near-infrared light harvesting of upconverting NaYF₄:Yb³⁺/Er³⁺-based amorphous silicon solar cells investigated by an optical filter

• Daiming Liu,
• Qingkang Wang and
• Qing Wang

Beilstein J. Nanotechnol. 2018, 9, 2788–2793, doi:10.3762/bjnano.9.260

• XRD results revealed the morphology and a phase transition from cubic to hexagonal NaYF4. Photoluminescence spectra indicated that the hexagonal NaYF4:Yb3+/Er3+ nanorods convert near-infrared light of 980 nm to the visible light with wavelength peaks at 654, 541 and 522 nm. Hence, the upconverting

• exhibited an 25% improved short-circuit current and an appreciable improvement of the near-infrared response of the external quantum efficiency. Moreover, because the size of the nanorods is comparable to the wavelength of visible light, the rods effectively scattered light, thus enhancing the visible light

• UC effect; however, it does not imitate the actual solar irradiation in practical devices. In the present work, the upconverting NaYF4:Yb3+/Er3+ nanorods were synthesized thorugh a hydrothermal method and their UC effect on NIR light harvesting in a-Si:H solar cell was scrutinized by using a facile

Oriented zinc oxide nanorods: A novel saturable absorber for lasers in the near-infrared

• Pavel Loiko,
• Tanujjal Bora,
• Josep Maria Serres,
• Haohai Yu,
• Magdalena Aguiló,
• Francesc Díaz,
• Uwe Griebner,
• Valentin Petrov,
• Xavier Mateos and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2018, 9, 2730–2740, doi:10.3762/bjnano.9.255

• , Applied Physics Department, School of Engineering Sciences, KTH Royal Institute of Technology, Isafjordsgatan 22, SE-164 40 Kista Stockholm, Sweden 10.3762/bjnano.9.255 Abstract Zinc oxide (ZnO) nanorods (NRs) oriented along the crystallographic [001] axis are grown by the hydrothermal method on glass

• nanorods; Q-switching; saturable absorption; solid-state lasers; zinc oxide; Introduction Zinc oxide (ZnO) is a well-known II–IV group wide-bandgap semiconductor (Eg = 3.37 eV), possessing a hexagonal wurtzite-type (sp. gr. P63mc) structure with unit cell parameters a = 3.25 Å, c = 5.20 Å. In recent years

• , a lot of attention has been paid to the studies of ZnO nanostructures of various shapes, including oriented nanorods (NRs), nanowires, nanobelts, nanoparticles, etc. for versatile photonic applications [1][2]. ZnO NRs are especially attractive for short-wavelength nano-devices due to their high

Low cost tips for tip-enhanced Raman spectroscopy fabricated by two-step electrochemical etching of 125 µm diameter gold wires

• Antonino Foti,
• Francesco Barreca,
• Enza Fazio,
• Cristiano D’Andrea,
• Paolo Matteini,
• Onofrio Maria Maragò and
• Pietro Giuseppe Gucciardi

Beilstein J. Nanotechnol. 2018, 9, 2718–2729, doi:10.3762/bjnano.9.254

• tips are TERS-active, while 50% of the tips have a radius of curvature smaller than 35 nm. Light emission from the tip apex Tightly coupled plasmonic metals, such as nanorods dimers [51], nanocubes on surfaces [52], or TERS tips in contact with surfaces [53][54], emit light over a broad continuum, even

Silencing the second harmonic generation from plasmonic nanodimers: A comprehensive discussion

• Jérémy Butet,
• Gabriel D. Bernasconi and
• Olivier J. F. Martin

Beilstein J. Nanotechnol. 2018, 9, 2674–2683, doi:10.3762/bjnano.9.250

• nanorods with hemispherical extremities and various gap distances. In order to unveil the role of the silencing effect, computations of the SHG considering only the surface second harmonic sources on specific parts of the dimers are also presented. The meshes describing the dimers are then slightly

• the SH surface currents [26][27]. Results and Discussion Gold dimers made of cylindrical nanorods We first consider the case of dimers made of gold nanorods, see Figure 1a. The diameter of the nanorods is 40 nm and their length is 85 nm. The smallest considered gap between the nanorods is 5 nm. Such

• by each nanorod. As expected, this mode redshifts as the gap between the nanorods decreases, i.e., as the coupling increases [2]. As a consequence of this coupling, the bonding dipolar mode for a dimer always arises at a longer wavelength than the longitudinal electric dipole mode of the

Polarization-dependent strong coupling between silver nanorods and photochromic molecules

• Gwénaëlle Lamri,
• Alessandro Veltri,
• Jean Aubard,
• Pierre-Michel Adam,
• Nordin Felidj and
• Anne-Laure Baudrion

Beilstein J. Nanotechnol. 2018, 9, 2657–2664, doi:10.3762/bjnano.9.247

• Abstract Active plasmonics is a key focus for the development of advanced plasmonic applications. By selectively exciting the localized surface plasmon resonance sustained by the short or the long axis of silver nanorods, we demonstrate a polarization-dependent strong coupling between the plasmonic

• resonance and the excited state of photochromic molecules. By varying the width and the length of the nanorods independently, a clear Rabi splitting appears in the dispersion curves of both resonators. Keywords: active plasmonics; photochromic molecules; plasmon; Rabi splitting; strong coupling

• polarization. In this context, a polarization-dependent external control of the plasmonic properties could be of prime interest for active plasmonic devices. In this work, we make use of the same protocol as in [16] and apply it to nanorods to demonstrate a polarization-dependent strong coupling between

Nanoantenna structures for the detection of phonons in nanocrystals

• Alexander G. Milekhin,
• Sergei A. Kuznetsov,
• Ilya A. Milekhin,
• Larisa L. Sveshnikova,
• Tatyana A. Duda,
• Ekaterina E. Rodyakina,
• Alexander V. Latyshev,
• Volodymyr M. Dzhagan and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2018, 9, 2646–2656, doi:10.3762/bjnano.9.246

• metal films, the enhancement was found to depend on the island aspect ratio and the size of the gap between nanoclusters [9][10]. It is worth noting that SEIRA is maximized for elongated metal nanoclusters (nanorods or nanoantennas) with a high aspect ratio (length-to-width ratio) and a small gap

Impact of the anodization time on the photocatalytic activity of TiO₂ nanotubes

• Jesús A. Díaz-Real,
• Geyla C. Dubed-Bandomo,
• Juan Galindo-de-la-Rosa,
• Luis G. Arriaga,
• Janet Ledesma-García and
• Nicolas Alonso-Vante

Beilstein J. Nanotechnol. 2018, 9, 2628–2643, doi:10.3762/bjnano.9.244

• synthesis methods resulting in a wide range of morphologies, such as mesoporous structures [4], microtubes [5], microdendrites, nanoparticles [6][7][8], nanorods [9][10], nanotubes [11][12][13], nanowires [14], and nanosheets [15][16]. Standing out from the rest of the synthesis techniques, electrochemical

ZnO-nanostructure-based electrochemical sensor: Effect of nanostructure morphology on the sensing of heavy metal ions

• Marina Krasovska,
• Vjaceslavs Gerbreders,
• Irena Mihailova,
• Andrejs Ogurcovs,
• Eriks Sledevskis,
• Andrejs Gerbreders and
• Pavels Sarajevs

Beilstein J. Nanotechnol. 2018, 9, 2421–2431, doi:10.3762/bjnano.9.227

• , nanostructures of ZnO were synthesized in four different morphologies: nanorods, nanoneedles, nanotubes and nanoplates. To determine the peculiarities of adsorption for each morphology, a series of electrochemical measurements were carried out using these nanostructured ZnO coatings on the working electrodes

• nanoplates), whereas the lowest sensitivity corresponded to ZnO nanorods with a large diameter (i.e., low surface-to-volume ratio). The efficiency of sedimentation is also related to the electronegativity of adsorbate: it has been shown that all observed ZnO morphologies exhibited significantly higher

• obtaining ZnO nanostructures in various morphologies, such as ZnO nanoneedles, nanorods, nanotubes, nanoplates, etc. Also the purpose of our previous research was to identify optimal growth parameters for obtaining a homogeneous, dense, well-aligned nanostructured ZnO coating with good adhesion to hard

Hierarchical heterostructures of Bi₂MoO₆ microflowers decorated with Ag₂CO₃ nanoparticles for efficient visible-light-driven photocatalytic removal of toxic pollutants

• Shijie Li,
• Wei Jiang,
• Shiwei Hu,
• Yu Liu,
• Yanping Liu,
• Kaibing Xu and
• Jianshe Liu

Beilstein J. Nanotechnol. 2018, 9, 2297–2305, doi:10.3762/bjnano.9.214

• the flower-like architecture. The representative ACO/BMO-30 displays the flower-like structure, the surface of which is decorated with Ag2CO3 nanoparticles (size: 10–50 nm, Figure 2c,d). In contrast, the previously reported Ag/Ag2CO3/Bi2MoO6 is composed of Bi2MoO6 nanoplates and Ag/Ag2CO3 nanorods

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

Beilstein J. Nanotechnol. 2018, 9, 2209–2235, doi:10.3762/bjnano.9.207

• expect a strong influence of the NC size on the CB level position favorable for the “band design” of the light absorber to fit the energy levels of various ETL materials. The Sn-based HPs can be synthesized in a variety of nanoscale morphologies, including 0D NCs, nanorods, nanoplatelets, etc., allowing

• in octadecene [130][133][134]. The shape of nanoscale Cs2SnI6 can be tuned quite easily by varying the duration of crystal growth. The reaction between Sn(IV) oleate and CsI yields ≈2.5 nm NCs in a minute after cesium iodide injection (Figure 7b), where the NCs transform into HP nanorods after a 5

• min ripening at 220 °C (Figure 7c) [133]. The Cs2SnI6 nanorods gradually transform into nanowires (Figure 7d) with the aspect ratio increasing from 3 to 28 after a 10 min reaction. At longer reaction times (30 min) nanowires transform into nanobelts (Figure 7e) that assemble into nanoplatelets with a

Electrospun one-dimensional nanostructures: a new horizon for gas sensing materials

• Muhammad Imran,
• Nunzio Motta and
• Mahnaz Shafiei

Beilstein J. Nanotechnol. 2018, 9, 2128–2170, doi:10.3762/bjnano.9.202

• SnO2 (ICTOs) NRs using electrospinning for room temperature NOx sensing. Pristine SnO2 nanorods show an average diameter of 474 nm, whereas the average diameter of 3ICNO (Sn:In atomic ratio 25:0.3) is 230 nm. The TEM images (Figure 11a–d) show that NPs are connected through a neck between grains that

• improve electron conduction. The dynamic response of the 3ICTO sensor is shown in Figure 11e. The 3ICTO nanorods show the highest response of 8.98 toward 100 ppm of NOx at room temperature. The response time for 3ICTO is 4.67 s, that is, 11-times

Synthesis of carbon nanowalls from a single-source metal-organic precursor

• André Giese,
• Sebastian Schipporeit,
• Volker Buck and
• Nicolas Wöhrl

Beilstein J. Nanotechnol. 2018, 9, 1895–1905, doi:10.3762/bjnano.9.181

• of four different morphologies (nanorods as well as thorny, straight and curled CNWs) by taking the surface diffusion into account. The surface diffusion depends on the particle energies and the substrate material and thus explains the influence of these parameters. Keywords: aluminium

• can be classified into four major classes: nanorods (Figure 3, sample 1), thorny structures (Figure 3, sample 2), straight CNWs (Figure 4, sample 3) and curled CNWs (Figure 4, sample 4). The mean wall length was measured to be between 127 and 391 nm for the curled CNWs and between 507 and 1152 nm for

• material. Although the thickness of the CNWs was not systematically measured in this work, it is clearly visible from the SEM images that the thickness is also varying with the structure. Nanorods and thorny CNWs show a higher thickness compared to the straight and the curled CNWs. The latter feature a

Toward the use of CVD-grown MoS₂ nanosheets as field-emission source

• Geetanjali Deokar,
• Nitul S. Rajput,
• Junjie Li,
• Francis Leonard Deepak,
• Wei Ou-Yang,
• Nicolas Reckinger,
• Carla Bittencourt,
• Jean-Francois Colomer and
• Mustapha Jouiad

Beilstein J. Nanotechnol. 2018, 9, 1686–1694, doi:10.3762/bjnano.9.160

• displays, X-ray sources and cold-cathode electron sources [2]. 1D and 2D materials such as carbon nanotubes [3], ZnO nanorods [1], LaB6 nanowires [2], SnS2 nanosheets (NSs) [4], vertically aligned graphene [5], WS2 nanotubes [6], MoSe2 nanosheets [7], and MoS2 NSs [8][9][10] are potential field-emitter

Optical near-field mapping of plasmonic nanostructures prepared by nanosphere lithography

• Gitanjali Kolhatkar,
• Alexandre Merlen,
• Jiawei Zhang,
• Chahinez Dab,
• Gregory Q. Wallace,
• François Lagugné-Labarthet and
• Andreas Ruediger

Beilstein J. Nanotechnol. 2018, 9, 1536–1543, doi:10.3762/bjnano.9.144

• induced surface deformation at the hot spots upon laser illumination. The localization of the hot spots is then indirectly revealed in the subsequent AFM scanning of the surface [26]. Similarly, Murazawa et al. [30] spin-coated a pattern of gold nanorods with a photoresist before irradiating the sample

Cathodoluminescence as a probe of the optical properties of resonant apertures in a metallic film

• Kalpana Singh,
• Evgeniy Panchenko,
• Babak Nasr,
• Amelia Liu,
• Lukas Wesemann,
• Timothy J. Davis and
• Ann Roberts

Beilstein J. Nanotechnol. 2018, 9, 1491–1500, doi:10.3762/bjnano.9.140

• nanogratings [15], plasmonic oligomers [16], dolmen arrangements of nanorods [17] and ring–disk dimers [18]. Fano resonances have also been observed in nanoholes such as coaxial apertures [19] and dolmen nanocavities [18]. The performance of an array of double split-ring cavities [20] as biosensors using Fano

Ag₂WO₄ nanorods decorated with AgI nanoparticles: Novel and efficient visible-light-driven photocatalysts for the degradation of water pollutants

• Shijie Li,
• Shiwei Hu,
• Wei Jiang,
• Yanping Liu,
• Yu Liu,
• Yingtang Zhou,
• Liuye Mo and
• Jianshe Liu

Beilstein J. Nanotechnol. 2018, 9, 1308–1316, doi:10.3762/bjnano.9.123

• Abstract To develop efficient and stable visible-light-driven (VLD) photocatalysts for pollutant degradation, we synthesized novel heterojunction photocatalysts comprised of AgI nanoparticle-decorated Ag2WO4 nanorods via a facile method. Various characterization techniques, including XRD, SEM, TEM, EDX

• nanorods as the Ag source. The as-prepared AgI/Ag2WO4 heterojunctions exhibited remarkably higher photocatalytic activity than pure Ag2WO4 toward the degradation of rhodamine B (RhB), methyl orange (MO) and para-chlorophenol (4-CP) under visible light. Based on a systematic characterization and study, a

• possible photocatalytic mechanism over AgI/Ag2WO4 was also elucidated in this work. Results and Discussion Preparation and characterization of catalysts Ag2WO4 nanorods decorated with AgI nanoparticles were prepared via an in situ anion-exchange method. Ag2WO4 nanorods were first synthesized by mixing

Room-temperature single-photon emitters in titanium dioxide optical defects

• Kelvin Chung,
• Yu H. Leung,
• Chap H. To,
• Aleksandra B. Djurišić and
• Snjezana Tomljenovic-Hanic

Beilstein J. Nanotechnol. 2018, 9, 1085–1094, doi:10.3762/bjnano.9.100

• ]. The defects are responsible for visible photoluminescence (PL) in TiO2 and have been observed in thin films [39][40][41], nanocrystals/nanoparticles [42][43][44][45][46][47], nanorods [48], nanotubes [49][50][51], nanosheets [52], nanoribbons [53] and fibres [54]. In material sciences, the PL spectrum

Review on nanoparticles and nanostructured materials: history, sources, toxicity and regulations

• Jaison Jeevanandam,
• Ahmed Barhoum,
• Yen S. Chan,
• Alain Dufresne and
• Michael K. Danquah

Beilstein J. Nanotechnol. 2018, 9, 1050–1074, doi:10.3762/bjnano.9.98

Surface-plasmon-enhanced ultraviolet emission of Au-decorated ZnO structures for gas sensing and photocatalytic devices

• T. Anh Thu Do,
• Truong Giang Ho,
• Thu Hoai Bui,
• Quang Ngan Pham,
• Hong Thai Giang,
• Thi Thu Do,
• Duc Van Nguyen and
• Dai Lam Tran

Beilstein J. Nanotechnol. 2018, 9, 771–779, doi:10.3762/bjnano.9.70

• . The higher magnification clearly shows that each sub-micrometer sphere is assembled from numerous nanorods pointing toward the center of the microsphere. Figure 1c reveals the formation of spherically shaped Au nanopaticles on the surface of ZnO sub-micrometer spheres. Au nanoparticles were adsorbed

• agglomeration, but also bind to the crystal seed surface. These are believed to play an important role in the weakening of grain growth and the assembly of nanorods. Owing to the stronger bonding between the active component of the deposition solution and substrate surface, the self-assembly of the nanorod

Tuning adhesion forces between functionalized gold colloidal nanoparticles and silicon AFM tips: role of ligands and capillary forces

• Sven Oras,
• Sergei Vlassov,
• Marta Berholts,
• Rünno Lõhmus and
• Karine Mougin

Beilstein J. Nanotechnol. 2018, 9, 660–670, doi:10.3762/bjnano.9.61

• accurate control of their intrinsic properties. For instance, Au nanospheres, nanocubes, nanorods and nanowires [10] have been routinely synthesized. Their physico-chemical and especially optical properties [11] of NPs strongly depend on their shape, size and spatial arrangement [12][13][14][15]. All these

Mechanistic insights into plasmonic photocatalysts in utilizing visible light

• Kah Hon Leong,
• Azrina Abd Aziz,
• Lan Ching Sim,
• Pichiah Saravanan,
• Min Jang and
• Detlef Bahnemann

Beilstein J. Nanotechnol. 2018, 9, 628–648, doi:10.3762/bjnano.9.59

• , in addition to gold nanorods (NRs) as plasmonic nanoantennas for an effective far red-to-NIR photocatalytic conversion. The electron–hole pairs were formed in some parts of BVO when BiVO4 encountered intense SPR-induced electric fields localized at Au NRs, and hence the entire photocatalytic system

Facile phase transfer of gold nanorods and nanospheres stabilized with block copolymers

• Yaroslav I. Derikov,
• Georgiy A. Shandryuk,
• Raisa V. Talroze,
• Alexander A. Ezhov and
• Yaroslav V. Kudryavtsev

Beilstein J. Nanotechnol. 2018, 9, 616–627, doi:10.3762/bjnano.9.58

• mass diblock copolymer of styrene and 2-vinylpyridine for ligand exchange at the nanoparticle surface. The method enables the preparation of stable sols of Au nanorods with sizes of up to tens of nanometers or Au nanospheres in various organic solvents. By comparing the optical absorbance spectra of Au

• the use of strong thiol and amine surfactants. Keywords: Au nanorods; block copolymers; optical absorbance spectroscopy; phase transfer; seeded growth method; Introduction The size effects that determine the functional characteristics of nanoparticles are no less important than their precise

• anisotropic. Their possible coupling with nanorods, as the simplest anisometric nanoparticles, is of emerging interest in recent experimental [6][7][8] and theoretical [9][10][11][12] research. In the case of Au nanoparticles, which are the focus of the current study, a number of synthetic routes are

Review: Electrostatically actuated nanobeam-based nanoelectromechanical switches – materials solutions and operational conditions

• Liga Jasulaneca,
• Jelena Kosmaca,
• Raimonds Meija,
• Jana Andzane and
• Donats Erts

Beilstein J. Nanotechnol. 2018, 9, 271–300, doi:10.3762/bjnano.9.29

• nanostructures (nanowires, nanotubes, nanorods, graphene) with a good uniformity and desired properties. The microfabrication routine may be supplemented with some bottom-up approaches. Dielectrophoresis [33], controlled nanomaterial growth [34], and nanomanipulation [9] have been demonstrated as useful methods

Gas-sensing behaviour of ZnO/diamond nanostructures

• Marina Davydova,
• Alexandr Laposa,
• Jiri Smarhak,
• Alexander Kromka,
• Neda Neykova,
• Josef Nahlik,
• Jiri Kroutil,
• Jan Drahokoupil and
• Jan Voves

Beilstein J. Nanotechnol. 2018, 9, 22–29, doi:10.3762/bjnano.9.4

• -terminated nanocrystalline diamond (NCD) films and/or n-type ZnO nanorods (NRs) have been obtained via a facile microwave-plasma-enhanced chemical vapour deposition process or a hydrothermal growth procedure. The morphology and crystal structure of the synthesized materials was analysed with scanning

• electron microscopy, X-ray diffraction measurements and Raman spectroscopy. The gas sensing properties of the sensors based on i) NCD films, ii) ZnO nanorods, and iii) hybrid ZnO NRs/NCD structures were evaluated with respect to oxidizing (i.e., NO2, CO2) and reducing (i.e., NH3) gases at 150 °C. The

• materials and a variety of studies have been carried out to improve the response of these gas sensors [1][2][3][4]. In particular, ZnO nanorods with n-type semiconducting behaviour and large surface-to-volume ratio have attracted great interest due to their wide range of application possibilities in solar