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

• nanoparticles in human volunteers and quantum dots ‘QDs’ in rat skin) and cause irritation (e.g., nano ZnO in zebrafish models) [10]. Oral exposure to ENMs can result in subsequent absorption in the GI tract and organ damage (e.g., nano Cu in mice via oral gavage damaged liver, spleen and kidneys, and nano ZnO

• product/system while RA provides an assessment a particular substance or component of a complex material. Hischier et al. [40] reviewed LCA case studies of several ENMs (e.g., CNTs, single walled CNTs, fullerenes, quantum dots and TiO2) and nano-enabled products (e.g., dye containing nano-TiO2 and carbon

Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

• Arpita Jana,
• Elke Scheer and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2017, 8, 688–714, doi:10.3762/bjnano.8.74

α-((4-Cyanobenzoyl)oxy)-ω-methyl poly(ethylene glycol): a new stabilizer for silver nanoparticles

• Jana Lutze,
• Miguel A. Bañares,
• Marcos Pita,
• Andrea Haase,
• Andreas Luch and
• Andreas Taubert

Beilstein J. Nanotechnol. 2017, 8, 627–635, doi:10.3762/bjnano.8.67

• , Zhang et al. [25] demonstrated the passivating effect of a PEG/silica hybrid coating on CdSe quantum dots. Thus, there is a growing interest in PEG-based stabilizers for a large variety of applications including catalysis, diagnostics, biology or biomedicine. There are numerous examples in which the

Modeling of the growth of GaAs–AlGaAs core–shell nanowires

• Qian Zhang,
• Peter W. Voorhees and
• Stephen H. Davis

Beilstein J. Nanotechnol. 2017, 8, 506–513, doi:10.3762/bjnano.8.54

• along certain crystallographic directions and quantum dots near the apexes of the shell are observed in AlGaAs shells. Controlling the formation of these core–shell heterostructures remains challenging. A two-dimensional model valid on the wire cross section, that accounts for capillarity in the faceted

• and Al-poor quantum dots) in the nanowire shell. There are two issues that need to be understood. One is the mechanism responsible for the morphological evolution of the shells. Analysis and simulation results suggest that deposition introduces facets not present on the equilibrium Wulff shapes. A

• the attachment rate of Al atoms is smaller there. Keywords: core–shell nanowires; heterostructures; mechanisms; quantum dots; Findings Core–shell nanowires with heterostructures hold great promise in photonic and electronic applications because of their high sensitivity to electronic and magnetic

Study of the surface properties of ZnO nanocolumns used for thin-film solar cells

• Neda Neykova,
• Jiri Stuchlik,
• Karel Hruska,
• Ales Poruba,
• Zdenek Remes and
• Ognen Pop-Georgievski

Beilstein J. Nanotechnol. 2017, 8, 446–451, doi:10.3762/bjnano.8.48

• preferred treatment for the preparation of thin-film solar cells based on ZnO NCs. The reported ZnO nanocolumns layer with a proper spacing could be used as a 3-D scaffold not only for amorphous silicon solar cells, but also for other absorbers with a short lifetime such as CuO, CuO2, FeS2, quantum dots or

Performance of colloidal CdS sensitized solar cells with ZnO nanorods/nanoparticles

• Anurag Roy,
• Partha Pratim Das,
• Mukta Tathavadekar,
• Sumita Das and
• Parukuttyamma Sujatha Devi

Beilstein J. Nanotechnol. 2017, 8, 210–221, doi:10.3762/bjnano.8.23

• − electrolyte with a costly Pt-based electrode. Reports on the synthesis of nanoscale CdS by using organic capping agents, polymers, surfactants, or enzymes reveal that they are not very user friendly techniques [17][18][19][20][21][22][23]. Therefore, rather taking a conventional path to synthesizing quantum

• dots (QDs) we followed a bioinspired strategy to synthesize such systems. In this work, bovine serum albumin (BSA) is selected as a biotemplating agent. BSA is a ubiquitous protein mainly present in blood and is a commonly used reagent in biological studies. Here, we have synthesized functionalized

Laser irradiation in water for the novel, scalable synthesis of black TiO_x photocatalyst for environmental remediation

• Massimo Zimbone,
• Giuseppe Cacciato,
• Mohamed Boutinguiza,
• Vittorio Privitera and
• Maria Grazia Grimaldi

Beilstein J. Nanotechnol. 2017, 8, 196–202, doi:10.3762/bjnano.8.21

• readily employed for water decontamination. In order to enhance the photocatalytic performance of TiO2 under visible (solar) irradiation, many efforts have been made in the last years, ranging from doping with N, C and transition metals [7][8][9], to coupling with narrow band gap semiconductor quantum

• dots [10], to the use of metal grafting [11][12][13][14] or plasmonic metal nanostructures [15][16][17][18][19] and the preparation of oxygen-deficient and/or hydrogen-rich TiOx [20][21][22]. We are interested, in particular, in this last approach. Hydrogenated black TiO2 has attracted attention due to

Obtaining and doping of InAs-QD/GaAs(001) nanostructures by ion beam sputtering

• Sergei N. Chebotarev,
• Alexander S. Pashchenko,
• Leonid S. Lunin,
• Elena N. Zhivotova,
• Georgy A. Erimeev and
• Marina L. Lunina

Beilstein J. Nanotechnol. 2017, 8, 12–20, doi:10.3762/bjnano.8.2

• and Solar Energy, Southern Scientific Center of Russian Academy of Sciences, 344006, 41, Chekhov Avenue, Rostov-on-Don, Russia 10.3762/bjnano.8.2 Abstract The features of InAs quantum dots obtained on GaAs(001) single-crystal substrates by ion-beam sputtering were investigated. It has been shown that

• in the range of ion energies of 150 to 200 eV at a temperature of 500 °C and a beam current of 120 µA InAs quantum dots with average dimensions below 15 nm and a surface density of 1011 cm−2 are formed. The technique of controlled doping of InAs/GaAs nanostructures using a SnTe solid-state source was

• barrier layer increases the intensity of photoluminescence peaks of the ground state and the first excited state of the InAs quantum dots. Keywords: 3D growth; doping; ion-beam sputtering; photoluminescence; quantum dots; Introduction Main interests of inorganic nanotechnology science are the study of

Zigzag phosphorene nanoribbons: one-dimensional resonant channels in two-dimensional atomic crystals

• Carlos. J. Páez,
• Dario. A. Bahamon,
• Ana L. C. Pereira and
• Peter. A. Schulz

Beilstein J. Nanotechnol. 2016, 7, 1983–1990, doi:10.3762/bjnano.7.189

• materials; constrictions; edge states; phosphorene nanoribbons; quantum dots; Introduction Low-dimensional systems have attracted attention over the past fifty years since the development of semiconductor epitaxial growth and deposition of metallic thin films [1]. The early scenario, back in the 1960s, as

• confinement in quantum dots leads to rich physical phenomena [37]. The correlation among the energy scales involved such as energy-level spacing of the constriction, charging energy and couplings allows us to estimate when charging effects would be important [38]. In the strong-coupling regime the wave

Facile fabrication of luminescent organic dots by thermolysis of citric acid in urea melt, and their use for cell staining and polyelectrolyte microcapsule labelling

• Nadezhda M. Zholobak,
• Anton L. Popov,
• Alexander B. Shcherbakov,
• Nelly R. Popova,
• Mykhailo M. Guzyk,
• Valeriy P. Antonovich,
• Alla V. Yegorova,
• Yuliya V. Scrypynets,
• Inna I. Leonenko,
• Alexander Ye. Baranchikov and
• Vladimir K. Ivanov

Beilstein J. Nanotechnol. 2016, 7, 1905–1917, doi:10.3762/bjnano.7.182

• crystals (quantum dots, Q-dots) are a good alternative to common fluorescent dyes in a variety of biomedical applications, mainly due to their high photostability and relatively large Stokes shift [1][2][3], but Q-dots typically contain heavy metals (lead, cadmium) and chalcogens (selenium, tellurium

• properties of low toxicity, being environmentally friendly, offering simple synthetic routes and low cost, as well as having comparable optical properties to traditional quantum dots and organic dyes [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Photoluminescent C-dots are superior in terms of

• nitric acid oxidation of carbon soot reduced the viability of HepG2 cells by 20%, at concentrations higher than 100 μg/mL [49]. The graphene quantum dots prepared with graphene oxide as starting material were markedly toxic for MCF-7 and MGC-803 (human gastric cancer) cells at concentrations higher than

Precise in situ etch depth control of multilayered III−V semiconductor samples with reflectance anisotropy spectroscopy (RAS) equipment

• Ann-Kathrin Kleinschmidt,
• Lars Barzen,
• Johannes Strassner,
• Christoph Doering,
• Henning Fouckhardt,
• Wolfgang Bock,
• Michael Wahl and
• Michael Kopnarski

Beilstein J. Nanotechnol. 2016, 7, 1783–1793, doi:10.3762/bjnano.7.171

• sequence of a semiconductor laser, mainly consisting of several layers of Ga(As)Sb quantum dots (QD) (as active material) embedded in GaAs, surrounded by n- and p-doped layers of Al0.5Ga0.5As (for the diode and waveguide structure), has been grown on an n-doped GaAs substrate (called sample type B, for

• ), the active area with eight layers of Ga(As)Sb quantum dots (QD) between 50 nm thick GaAs barriers (B3), the lower n-Al0.5Ga0.5As cladding (B2) and, finally, the n-GaAs buffer and substrate (B1). The different properties of the layers during etching become particularly obvious, when taking a look at

Multiwalled carbon nanotube hybrids as MRI contrast agents

• Nikodem Kuźnik and
• Mateusz M. Tomczyk

Beilstein J. Nanotechnol. 2016, 7, 1086–1103, doi:10.3762/bjnano.7.102

• PAH-covered oMWCNT, followed by the introduction of CdTe quantum dots leading to CdTe-SPIO-oMWCNT#Chen nanohybrids. Finally, we showed that oxidized nanotubes are attractive for hard Lewis acids, e.g., Fe3+ ions, and form stable nanomolecular complexes, namely Fe-oMWCNT#Kuźnik [41]. Further covalent

• therefore increasing the resulting relaxivity [36]. On the other hand, superparamagnetic nanoparticles, both in the most common SPIO and in others (e.g., CoFe2O4, CdTe quantum dots), anchored on the nanotube net require an extension of the SBM theory [13][14]. Moreover, the hypothesis of CNT as a conducting

Photocurrent generation in carbon nanotube/cubic-phase HfO₂ nanoparticle hybrid nanocomposites

• Protima Rauwel,
• Augustinas Galeckas,
• Martin Salumaa,
• Frédérique Ducroquet and
• Erwan Rauwel

Beilstein J. Nanotechnol. 2016, 7, 1075–1085, doi:10.3762/bjnano.7.101

• conduction via the CNT. To date, numerous studies have been reported on the decoration of CNTs with metal oxides including TiO2 [7][8] and ZnO [9] for solar cell applications and SnO2 for gas sensors. Reports on the fabrication of an all carbon nanocomposite combining CNTs, graphene and carbon quantum dots

• range along with the plasmonic effect of the CNTs, which also serves to conduct charges from the surface states of the nanoparticles to an external load. To put the present work into perspective, we note that fabrication of all-carbon nanocomposites by replacing HfO2 by carbon quantum dots (CQDs) might

The influence of phthalocyanine aggregation in complexes with CdSe/ZnS quantum dots on the photophysical properties of the complexes

• Irina V. Martynenko,
• Anna O. Orlova,
• Vladimir G. Maslov,
• Anatoly V. Fedorov,
• Kevin Berwick and
• Alexander V. Baranov

Beilstein J. Nanotechnol. 2016, 7, 1018–1027, doi:10.3762/bjnano.7.94

• Technology, Dublin 8, Ireland 10.3762/bjnano.7.94 Abstract The formation of nonluminescent aggregates of aluminium sulfonated phthalocyanine in complexes with CdSe/ZnS quantum dots causes a decrease of the intracomplex energy transfer efficiency with increasing phthalocyanine concentration. This was

• ; Förster resonance energy transfer; photosensitizer; semiconductor nanocrystals; tetrapyrroles; Introduction Semiconductor quantum dots (QDs) and their complexes with organic molecules have been a subject of extensive research during the last couple of decades. In particular, complexes of QDs and

• QDs results in a significant increase in efficiency of FRET between QDs and monomeric molecules. Results and Discussion QD–phthalocyanine complex formation Water soluble CdSe/ZnS quantum dots capped with 2-(dimethylamino)ethanethiol (DMAET) with a core diameter of 5 nm [35] were used in the study. UV

Highly compact refractive index sensor based on stripe waveguides for lab-on-a-chip sensing applications

• Chamanei Perera,
• Kristy Vernon,
• Elliot Cheng,
• Juna Sathian,
• Esa Jaatinen and
• Timothy Davis

Beilstein J. Nanotechnol. 2016, 7, 751–757, doi:10.3762/bjnano.7.66

• quantum dots (QDs) with emission wavelength at 655 nm (from Invitrogen Cat. No. Q21321MP). An optimum QD spacer layer thickness of 18 nm SiO2 was selected [23]. The sensor designs with separations between two outer arms of 300 nm (Figure 4a) and 200 nm (Figure 4b) were observed under QD luminescence. We

Tight junction between endothelial cells: the interaction between nanoparticles and blood vessels

• Yue Zhang and
• Wan-Xi Yang

Beilstein J. Nanotechnol. 2016, 7, 675–684, doi:10.3762/bjnano.7.60

• exposure to NPs (polystyrene nanoparticles, quantum dots, single-wall carbon nanotubes) results in the disruption of the alveolar epithelial barrier, the extent of which also depends on the composition, shape and surface charge of the NPs [31]. Carbon nanotubes also show their capacity to penetrate the

• 8-oxoguanine (8-oxoG) as marker showed the attenuation of both active forms of ERK and AKT protein expression caused by Ag NPs [77]. Another research evaluating the toxicity of quantum dots, found that the production of tumor necrosis factor (TNF)-α and CXC-chemokine ligand (CXCL) 8 in human primary

Charge and heat transport in soft nanosystems in the presence of time-dependent perturbations

• Alberto Nocera,
• Carmine Antonio Perroni,
• Vincenzo Marigliano Ramaglia and
• Vittorio Cataudella

Beilstein J. Nanotechnol. 2016, 7, 439–464, doi:10.3762/bjnano.7.39

• forces are close to resonance with the vibration of the dot. We have shown that the amplification is robust against temperature, leading to the prediction that, different from expectation, slowly oscillating quantum dots could have pumping effects measurable up to high temperatures. The review is

Hemolysin coregulated protein 1 as a molecular gluing unit for the assembly of nanoparticle hybrid structures

• Tuan Anh Pham,
• Andreas Schreiber,
• Elena V. Sturm (née Rosseeva),
• Stefan Schiller and
• Helmut Cölfen

Beilstein J. Nanotechnol. 2016, 7, 351–363, doi:10.3762/bjnano.7.32

• nanotechnological building block [19][20] (protein data bank (PDB) code: 1Y12) for the fabrication of magnetically and plasmonically active assemblies. The cysteine-modified mutant (Hcp1_cys3) of the native Hcp1 protein is proven to be a great candidate, triggering the assembly of CdSe quantum dots and Au NPs into

Single-molecule mechanics of protein-labelled DNA handles

• Vivek S. Jadhav,
• Dorothea Brüggemann,
• Florian Wruck and
• Martin Hegner

Beilstein J. Nanotechnol. 2016, 7, 138–148, doi:10.3762/bjnano.7.16

• detail and to facilitate further single-molecule spectroscopy applications we have coupled streptavidin-modified quantum dots (Q-dot 525, Hayward CA) to the 3' end of DIG-λ-DNA-Bio constructs with 48502 bp length, which were tethered to anti-DIG beads held by suction with a pipette (Figure 1f). This

• out of focus or the known blinking of fluorescing quantum dots [32] (Figure 8). This single molecule fluorescence experiment clearly visualizes the specific binding of a protein to the biotinylated end of the dsDNA. Since the dsDNA was not labelled with intercalating dyes in this fluorescence

• high-resolution dual trap OT. f) End-labelled DIG-λ-DNA-biotin bound to an anti-DIG bead (3.4 μm) held by a micropipette. Flow forces elongate the λ-DNA molecule that is tethered at one end to the microsphere. The streptavidin-modified end (labelled with quantum dots) is freely floating in the

Effects of spin–orbit coupling and many-body correlations in STM transport through copper phthalocyanine

• Benjamin Siegert,
• Andrea Donarini and
• Milena Grifoni

Beilstein J. Nanotechnol. 2015, 6, 2452–2462, doi:10.3762/bjnano.6.254

• in our model. The fundamental reason for neglecting it is the large ratio between the hopping integrals (of the order of electronvolts) and the SOI (ξCu ≈ 100 meV), which also justifies our perturbative analysis in terms of molecular orbitals. However, for molecular quantum dots with comparable SOI

Silica-coated upconversion lanthanide nanoparticles: The effect of crystal design on morphology, structure and optical properties

• Uliana Kostiv,
• Miroslav Šlouf,
• Hana Macková,
• Alexander Zhigunov,
• Hana Engstová,
• Katarína Smolková,
• Petr Ježek and
• Daniel Horák

Beilstein J. Nanotechnol. 2015, 6, 2290–2299, doi:10.3762/bjnano.6.235

• tracking [8], bioimaging [9] and photodynamic therapy [10]. Lanthanide-doped upconversion nanoparticles emit visible light upon excitation by near-IR light (NIR). Compared with organic dyes and semiconductor quantum dots, upconversion nanoparticles have attractive chemical and optical properties, as well

A single-source precursor route to anisotropic halogen-doped zinc oxide particles as a promising candidate for new transparent conducting oxide materials

• Daniela Lehr,
• Markus R. Wagner,
• Johanna Flock,
• Julian S. Reparaz,
• Clivia M. Sotomayor Torres,
• Alexander Klaiber,
• Thomas Dekorsy and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2015, 6, 2161–2172, doi:10.3762/bjnano.6.222

• require quite demanding, high-vacuum equipment, correct process parameters are often difficult to find, and nanostructures different from thin films cannot be obtained. For the preparation of semiconductor nanomaterials such as colloidal particles, quantum dots or porous materials bottom-up synthesis

Mapping bound plasmon propagation on a nanoscale stripe waveguide using quantum dots: influence of spacer layer thickness

• Chamanei S. Perera,
• Alison M. Funston,
• Han-Hao Cheng and
• Kristy C. Vernon

Beilstein J. Nanotechnol. 2015, 6, 2046–2051, doi:10.3762/bjnano.6.208

• incoupling to the desired mode. A homogeneous thin layer of quantum dots was used to image the near field intensity of the propagating plasmons on the waveguide. We observed that the photoluminescence is quenched when the QD to metal surface distance is less than 10 nm. The optimised spacer layer thickness

• ). LRSPPs have been shown to have large propagation lengths in the visible light range, greater than 10 µm [6]. When quantum dots (QDs) are placed in the vicinity of propagating plasmons, QDs can be locally excited by the plasmon if the plasmon frequency lies within the absorption spectral range of the QDs

• outcoupled light from the opposite end of the waveguide was observed. CCD image of the outcoupling at the stripe end is shown in Figure 6b. Finally, the samples were covered with SiO2 spacer layers of thicknesses 5, 10, 15, 20, 25, 30, 40, and 50 nm using a PVD 75 electron beam evaporator. Quantum dots with

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

• ENMs were TiO2 (550–5,500 t/year), SiO2 (55–55,000 t/year), AlOx (55–5,500 t/year), ZnO (55–550 t/year), carbon nanotubes (CNT; 55–550 t/year), FeOx (5.5–5,500 t/year), CeOx and Ag (both 5.5–550 t/year), fullerenes and quantum dots (both 0.6-5.5 t/year) [5]. Warningly, the increasing production and use

Nonlinear optical properties of near-infrared region Ag₂S quantum dots pumped by nanosecond laser pulses

• Li-wei Liu,
• Si-yi Hu,
• Yin-ping Dou,
• Tian-hang Liu,
• Jing-quan Lin and
• Yue Wang

Beilstein J. Nanotechnol. 2015, 6, 1781–1787, doi:10.3762/bjnano.6.182

• Abstract This study investigates near-infrared region Ag2S quantum dots (QDs) and their nonlinear optical response under 532 nm nanosecond laser pulses. Our experimental result shows that nonlinear transmission is reduced from 0.084 to 0.04. The observed narrowing behavior of the output pulse width shows

• . Keywords: nonlinear optics; quantum dots; silver sulfide (Ag2S); strong absorption; Introduction Quantum dots (QDs) are semiconductor nanostructures with a size from 3 to 10 nm [1]. Through tailoring their size and composition, the emission wavelength of the quantum dots can be tuned from 650 to 1250 nm

• scanning spectrophotometer (UV-3101PC from Shimadzu). Figure 1b shows the EDS spectra of Ag2S QDs clearly indicating Ag and S as constituents. The two sharp peaks at 0 and 0.15 keV have no relation to the Ag2S quantum dots, and are caused by a measurement error. COMSOL Multiphysics 4.2a was used to