Effect of Anderson localization on light emission from gold nanoparticle aggregates

• Mohamed H. Abdellatif,
• Marco Salerno,
• Gaser N. Abdelrasoul,
• Ioannis Liakos,
• Alice Scarpellini,
• Sergio Marras and
• Alberto Diaspro

Beilstein J. Nanotechnol. 2016, 7, 2013–2022, doi:10.3762/bjnano.7.192

• the aggregated density and pattern as explained by the theory. Figure 4a–c shows the UV–vis absorption spectra of AuNPs in solution, deposited on quartz and deposited on glass substrate, respectively. The absorption band of AuNPs on quartz is quite broad, with a FWHM of ≈150 nm, while for the AuNPs on

• a glass substrate, the band is less broad (FWHM ≈100 nm), due to lower aggregation, as evidenced in the SEM images of Figure 2. The second peak for the glass substrate is due to the splitting in the plasmonic resonance due to the hybridization effect [19]. The absorption spectra of AuNPs in solution

• on a glass substrate (blue data points) and, on a quartz substrate (black data points). The profile of PL emission from the pristine AuNPs in aqueous solution is also shown for comparison (red data points). Absorption spectra of AuNPs, either in solution (black line) or drop cast on glass (red line

A dioxaborine cyanine dye as a photoluminescence probe for sensing carbon nanotubes

• Mohammed Al Araimi,
• Petro Lutsyk,
• Anatoly Verbitsky,
• Yuri Piryatinski,
• Mykola Shandura and
• Aleksey Rozhin

Beilstein J. Nanotechnol. 2016, 7, 1991–1999, doi:10.3762/bjnano.7.190

• high potential to be used as an effective PL probe for the detection of carbon nanotubes considering that there is clear dependence of the RET response on the SWNT concentration (see Supporting Information File 1, Figure S1). Figure 3 shows the absorption spectra for the mixture of DOB-719 with the

• the mixture of DOB-719 with the SWNT (Figure 5c,d) registered in the range of λEX = 400–750 nm and λEM = 600–800 nm. The PL peak with λEX = 685 nm and λEM = 720 nm (Figure 5) correlates with the monomeric peak in the absorption spectra at 687 nm (Figure 3a and Supporting Information File 1, Figure S2

• initial SWNT dispersion with SDBS to maintain the dye admixture with the SWNTs at the premicellar concentration (0.065 mg/mL). The origin and level of purity for all materials used in this manuscript are described in Supporting Information File 1. Experimental setup The absorption spectra in the visible

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

• O-dots consists of different oscillators joined together by stronger bonds, (for example, by σ-bonds between carbon atoms). Due to the presence of multiple independent oscillators, the absorption spectra of type-II O-dots do not consist of individual bands, (in contrast to type-I O-dots). Another

• acid/urea in the precursor mixtures from 1:1 to 1:2, 1:3, 1:4 and 1:5, the absorption spectra of products were changed (Figure 1) and the luminescence emission maxima were shifted to higher wavelengths (Figure 2, left). The dependence of luminescence intensity from the citric acid/urea molar ratio was

• experiments conducted was five. Statistical differences within and between groups were verified using one-way analysis of variance (ANOVA). Absorption spectra of citric acid heated in the urea melt (1:1, 1:2, 1:3, 1:4 and 1:5 molar ratios) at 160 °C for 120 min (with subsequent dissolution of the reaction

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

• -established in the visual regime, measures the optical thickness change of a sensitive layer caused, e.g., by binding an analyte. When operated in the mid-infrared range the sensor provides additional information via weak absorption spectra (fingerprints). The originally poor spectra are magnified by surface

• evanescent field of a guided wave (as is the above-mentioned MZI sensor), will show only a moderate absorption spectra, as the sensing volume is limited by the penetration depth of the evanescent field. This fact is both an advantage and a disadvantage. Biosensors often operate in aqueous solution, which

• . The deposition of the water molecules leads to an increase of water absorption features due to adsorption of water molecules to the nanoparticle layer on top of the ATR waveguide. In the current work, water absorption spectra have been studied under the influence of silver nanoparticles present in an

Role of RGO support and irradiation source on the photocatalytic activity of CdS–ZnO semiconductor nanostructures

• Suneel Kumar,
• Rahul Sharma,
• Vipul Sharma,
• Gurunarayanan Harith,
• Vaidyanathan Sivakumar and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2016, 7, 1684–1697, doi:10.3762/bjnano.7.161

• by recording the absorbance using a UV–vis spectrophotometer. Characterizations The UV–visible absorption spectra of the samples were recorded using Shimadzu UV-2450 spectrophotometer in the wavelength range from 200 to 800 nm. Fourier transform infrared (FTIR) spectra were collected using Agilent

• spectrum of the binary nanocomposite (CdS–ZnO) shows the absorption both in the UV and the visible region confirming the presence of both CdS and ZnO in the composite. Finally the absorption spectra of ternary nanocomposite (CdS–ZnO–RGO) shows an absorption near 250 nm, which indicates the red shift of the

• spectra of (a) GO, (b) ZnO, (c) CdS, (d) CdS–ZnO and (e) CdS–ZnO–RGO nanocomposite. UV–vis absorption spectra of GO, ZnO NR, CdS NP, CdS–ZnO and CdS–ZnO–RGO nanocomposite. Time-dependent UV–vis spectra of photocatalytic degradation of MO: (a) visible light irradiation from a solar simulator using CdS–ZnO

Hydrophilic silver nanoparticles with tunable optical properties: application for the detection of heavy metals in water

• Paolo Prosposito,
• Federico Mochi,
• Erica Ciotta,
• Mauro Casalboni,
• Fabio De Matteis,
• Iole Venditti,
• Laura Fontana,
• Giovanna Testa and
• Ilaria Fratoddi

Beilstein J. Nanotechnol. 2016, 7, 1654–1661, doi:10.3762/bjnano.7.157

• sensitivity of the sensor as much as possible. Figure 2 shows the absorption spectra of the AgNP-3MPS solution. It shows a sharp peak at 404 nm. Its FWHM is 92 nm instead of 170 nm as obtained by the first synthetic method (synthesis a). It should be noted that the FWHM of the AgNP solution without capping

• AgNPs contained in a fixed volume of water, a fixed volume of water was added containing the ions with the specific final concentration. After the mixing, we waited for five minutes before measuring the absorption spectra in order to allow for the complete interaction with the NPs. The sensitivity of

• the concentration of metal ions. In Figure 8 we report the normalized intensity, the peak wavelength and the FWHM of the absorption spectra obtained with different nickel ion concentrations (from 0–1 ppm). The reduction of intensity with the increase of the ion concentration can be ascribed to the

High performance Ce-doped ZnO nanorods for sunlight-driven photocatalysis

• Bilel Chouchene,
• Tahar Ben Chaabane,
• Lavinia Balan,
• Emilien Girot,
• Kevin Mozet,
• Ghouti Medjahdi and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2016, 7, 1338–1349, doi:10.3762/bjnano.7.125

• analysed using the BET (Brunauer–Emmett–Teller) method. All the optical measurements were performed at room temperature (20 ± 1°C) under ambient conditions. Absorption spectra of liquid samples were recorded on a Thermo Scientific Evolution 220 UV–visible spectrophotometer. DRS were recorded on a Shimadzu

Tunable longitudinal modes in extended silver nanoparticle assemblies

• Serene S. Bayram,
• Klas Lindfors and
• Amy Szuchmacher Blum

Beilstein J. Nanotechnol. 2016, 7, 1219–1228, doi:10.3762/bjnano.7.113

• interactions in assembly size and morphology. Spectral and morphological evolutions of the AgNPs assemblies are followed via UV–visible spectroscopy and transmission electron microscopy (TEM). Spectroscopic measurements are compared to calculations of the absorption spectra of randomly assembled silver chains

• . Linear aggregates are obtained by restricting the attachment point of a new particle to within a narrow solid angle defined by the growing chain. When the allowed solid angle is large, dense, isotropic aggregates are obtained. Figure 2B shows the absorption spectra for chains with length ranging from 1

• change of the polarizability due to the modified dielectric environment of the particles. In order to study the influence of this, we calculated the absorption spectra for aggregates of particles with a polarizability scaled from the value given by the quasi-static expression (see Experimental section

Manufacturing and investigation of physical properties of polyacrylonitrile nanofibre composites with SiO₂, TiO₂ and Bi₂O₃ nanoparticles

• Tomasz Tański,
• Wiktor Matysiak and
• Barbara Hajduk

Beilstein J. Nanotechnol. 2016, 7, 1141–1155, doi:10.3762/bjnano.7.106

• concentration by weight of the used reinforcing phase, which was as follows: 0%, 4%, 8% and 12% for each type of nanoparticles. The width of the band gap was determined on the basis of the absorption spectra of radiation (UV–vis) and ellipsometry methods. Spectroscopic ellipsometry has been used in order to

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

• MWCNTs do not emit light but instead expose their discrete electronic structure in the absorption spectra. The hybrid material manifests characteristic absorption features with a gradual merger of the MWCNT π-plasmon resonance band with the intrinsic defect band and fundamental edge of HfO2. The

• , the electrons can be optically excited via a series of valence-to-conduction band transitions, resulting in characteristic vHS peaks in absorption spectra. However, since holes are instantly filled with readily available electrons, no excitons are formed, and consequently, no photoluminescence (PL

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

• the concentration of donors bonded in complexes with acceptors. and are the concentrations of donors bound to acceptor monomers and aggregates, respectively. and are the concentrations of acceptor in monomeric and aggregated forms in complexes, respectively. Typically, the absorption spectra of

• obtained with a value of the extinction ratio = 1.20. This is in good accordance with the extinction ratio = 1.15 ± 0.05 obtained from the absorption spectra. The relevant calculations of the extinction of PcSz molecules in aggregates are presented in the Supporting Information File 4. The most favorable

• –vis absorption and PL detection UV–visible absorption spectra were recorded using a UV3600 (Shimadzu) spectrophotometer. Steady-state photoluminescence spectra were measured using a Cary Eclipse (Varian) spectrofluorometer. Time-resolved PL spectroscopy was performed using a time-correlated single

Phenalenyl-based mononuclear dysprosium complexes

• Yanhua Lan,
• Andrea Magri,
• Olaf Fuhr and
• Mario Ruben

Beilstein J. Nanotechnol. 2016, 7, 995–1009, doi:10.3762/bjnano.7.92

• at room temperature the absorption spectra of the diluted DMSO solutions of complexes 1–4 and of the sublimed product 4’. For comparison, UV–vis spectra were recorded for the free HPLN ligand in parallel. The spectra of the three dysprosium compounds present a similar pattern, as illustrated in

• bands can result from slight differences in the structures of the complexes. As a consequence of the few milligrams of material obtained by the sublimation process, we were unable to compare the extinction coefficients of the complexes. As observed previously in the absorption spectra, the ligand

• without additional matrix compound other than the sample itself. The absorption spectra were acquired at room temperature for diluted (2.0 × 10−6 M) DMSO (spectrophotometric grade) solutions on a Cary 500 Scan UV–vis–NIR spectrophotometer using a 1 cm quartz cell. Emission spectra were recorded at room

Optical absorption signature of a self-assembled dye monolayer on graphene

• Tessnim Sghaier,
• Sylvain Le Liepvre,
• Céline Fiorini,
• Ludovic Douillard and
• Fabrice Charra

Beilstein J. Nanotechnol. 2016, 7, 862–868, doi:10.3762/bjnano.7.78

• combining two successive images with downward and upward slow-scan directions. Optical absorption spectra at normal incidence were obtained with a Perkin-Elmer Lambda 650 spectrometer. Optical microspectroscopy was adapted on an Olympus IX71 microscope equipped with an Ocean Optics spectrometer QE-Pro

Hierarchical coassembly of DNA–triptycene hybrid molecular building blocks and zinc protoporphyrin IX

• Rina Kumari,
• Sumit Singh,
• Mohan Monisha,
• Sourav Bhowmick,
• Anindya Roy,
• Neeladri Das and
• Prolay Das

Beilstein J. Nanotechnol. 2016, 7, 697–707, doi:10.3762/bjnano.7.62

• fluorescence (λem = 530 nm) and absorption spectra (λabs = 500 nm). We found that at a given concentration of DHR 123 and a fixed irradiation time, the composite DNA nanofibers that were constructed from assemblies of DNA–TPA triconjugates in the presence of Zn PpIX produced the maximum ROS as compared to a

• absorption spectra and steady-state fluorescent spectra of rhodamine 123 quantifying the photocatalytic activity of nanofibers (S1 DNA–TPA/S2 DNA–TPA triconjugate Zn PpIX coassembly) and their control. Schematic representation of creation of nanostructures from DNA–TPA hybrid self-assembly. The number and

Gold nanoparticles covalently assembled onto vesicle structures as possible biosensing platform

• M. Fátima Barroso,
• M. Alejandra Luna,
• Juan S. Flores Tabares,
• Cristina Delerue-Matos,
• N. Mariano Correa,
• Fernando Moyano and
• Patricia G. Molina

Beilstein J. Nanotechnol. 2016, 7, 655–663, doi:10.3762/bjnano.7.58

• . Figure 2 shows the absorption spectra of the glycerol solutions of the metallic precursor and the AuNPs synthesized with different times of irradiation (λirridiation = 300 nm). Glycerol acts as solvent and as the reducing agent and the glycerol oxidation products are able to stabilize the AuNPs [26

Bacteriorhodopsin–ZnO hybrid as a potential sensing element for low-temperature detection of ethanol vapour

• Saurav Kumar,
• Sudeshna Bagchi,
• Senthil Prasad,
• Anupma Sharma,
• Ritesh Kumar,
• Rishemjit Kaur,
• Jagvir Singh and
• Amol P. Bhondekar

Beilstein J. Nanotechnol. 2016, 7, 501–510, doi:10.3762/bjnano.7.44

• scanning electron microscope (SEM, Hitachi) with an accelerating voltage of 5–15 kV. The film thickness was measured using a surface profilometer in contact mode (Taly-surf PGI 120). Raman and optical spectral analysis The optical absorption spectra of all the nanostructures were recorded using a UV–vis

Antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution

• Brunella Perito,
• Emilia Giorgetti,
• Paolo Marsili and
• Maurizio Muniz-Miranda

Beilstein J. Nanotechnol. 2016, 7, 465–473, doi:10.3762/bjnano.7.40

• NP size. The UV–vis absorption spectra, instead, evidenced a larger content of oxidized silver on the surface of the ps-ablated nanoparticles. This results in the release of more silver ions, which is recognized to be quite important for the antimicrobial activity [15][16]. For the colloids obtained

• counted as CFU/mL. The MBC was identified as the lowest concentration of the antibacterial agent that reduced the viability of the initial bacterial inoculum by ≥99.9%. UV–vis absorption spectra of AgNPs in colloidal suspensions obtained with (a) ps and (b) ns laser ablation. Typical TEM image and size

• characterization AgNPs were prepared by PLAL. The experimental setup has been previously described by Giorgetti et al. [31], and the specific fabrication conditions are reported in the Experimental section. The list of samples with their characteristics is shown in Table 1. Figure 1 reports the UV–vis absorption

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

• to collect the species in the mixture for TEM and HRTEM. Finally, the solution with a TEM grid was frozen in liquid nitrogen for 10 min in the magnetic field. The frozen sample was removed and lyophilized under 0.01 mbar vacuum over 2 days. Methods The absorption spectra were recorded on a UV–vis

Influence of calcium on ceramide-1-phosphate monolayers

• Joana S. L. Oliveira,
• Gerald Brezesinski,
• Alexandra Hill and
• Arne Gericke

Beilstein J. Nanotechnol. 2016, 7, 236–245, doi:10.3762/bjnano.7.22

• constant at the desired value with an accuracy of ±0.1 °C. Infrared reflection–absorption spectroscopy (IRRAS) Infrared reflection–absorption spectra were recorded on a Vertex 70 FTIR spectrometer (Bruker, Ettlingen, Germany). The setup includes a MCT detector cooled with liquid nitrogen and coupled to a

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

• absorption spectra. The mobility of the PDHs was expected to be less than that of the unlabelled DIG-biotin strands and was confirmed with band shifts in agarose gel electrophoresis tests (Figure 2). 1.8% (a) and 1% gel (b) images are shown next to each other, these shifts are more prominent in gel lanes 2

Dependence of lattice strain relaxation, absorbance, and sheet resistance on thickness in textured ZnO@B transparent conductive oxide for thin-film solar cell applications

• Kuang-Yang Kou,
• Yu-En Huang,
• Chien-Hsun Chen and
• Shih-Wei Feng

Beilstein J. Nanotechnol. 2016, 7, 75–80, doi:10.3762/bjnano.7.9

• acquired by the use of a Gatan monoCL3 spectrometer in a JEOL JSM 7000F SEM system. The absorption spectra were acquired with a U-3900 spectrophotometer (model 2J2-0015) at room temperature. The Raman spectra were recorded in the backscattering configuration using a Jobin Yvon-Horiba micro-Raman system

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

• arrays by means of the Langmuir–Blodgett technique. (a) π–A and Cs−1–A isotherm for AgNCs at the water–air interface. Optical images (650 × 750 µm) of the LB film of AgNC transferred at different surface pressures along the isotherm. (b) Absorption spectra of AgNC dispersion (dotted line) of a 1 LB layer

Sonochemical co-deposition of antibacterial nanoparticles and dyes on textiles

• Ilana Perelshtein,
• Anat Lipovsky,
• Nina Perkas,
• Tzanko Tzanov and
• Aharon Gedanken

Beilstein J. Nanotechnol. 2016, 7, 1–8, doi:10.3762/bjnano.7.1

• measuring their absorption spectra. The results are presented in (Table 2 and Figure 8). When RO16 was sonochemically coated with metal oxide, the decrease in the intensity of color was smaller in comparison to the leaching observed for the sonochemically deposited dye alone. This might indicate a possible

Chemiresistive/SERS dual sensor based on densely packed gold nanoparticles

• Sanda Boca,
• Cosmin Leordean,
• Simion Astilean and
• Cosmin Farcau

Beilstein J. Nanotechnol. 2015, 6, 2498–2503, doi:10.3762/bjnano.6.259

• biological molecules. Optical absorption spectra of the colloidal suspension recorded before and after incubation with folic acid confirmed the capping of AuNPs (redshift of the dipolar plasmon band) (Figure S1, Supporting Information File 1). DLS measurements correlate with the optical absorption results

Self-organization of gold nanoparticles on silanated surfaces

• Htet H. Kyaw,
• Salim H. Al-Harthi,
• Azzouz Sellai and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2015, 6, 2345–2353, doi:10.3762/bjnano.6.242

• driving force for migrating on the surface during annealing process leading to no specific reorganisation of AuNPs. Figure 8 shows ultraviolet–visible absorption spectra of AuNPs deposited on APTES-functionalized glass substrates (before and after annealing in air and vacuum). Surface plasmon resonance

• ) the valence band maximum of same samples obtained by linear extrapolations. AFM images of Au NPs deposited on silanized glass substrates, (a) without annealing (as deposited) (b) annealed in vacuum (c) annealed in air at 600 °C for 1 h. UV–visible absorption spectra of AuNPs deposited on APTES