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

• -plasma for 1, 5, 10 and 25 min. The measured PDS absorptance spectra reflect the absorption edge, Urbach tail, absorption on defects and free-carrier absorption (proportional to the concentration of free carriers). All optical absorptance spectra show the optical absorption edge at a photon energy of 3.3

Selective photodissociation of tailored molecular tags as a tool for quantum optics

• Ugur Sezer,
• Philipp Geyer,
• Moritz Kriegleder,
• Maxime Debiossac,
• Armin Shayeghi,
• Markus Arndt,
• Lukas Felix and
• Marcel Mayor

Beilstein J. Nanotechnol. 2017, 8, 325–333, doi:10.3762/bjnano.8.35

• yet generally scalable to covalently bound organic molecules. In particular, large biomolecules – which are interesting candidates for quantum-interference experiments and gas-phase metrology [7] – often neither ionize nor dissociate upon absorption of a single photon, not even at 7.9 eV photon energy

• [21]. Here we address this challenge and study tailored tags that are optimized to respond to light of lower photon energy with cleavage at a deterministic location. Click chemistry shall then allow attaching them to a wide class of analyte molecules and thus solve the problem. Results Design of the

• sections at 254 nm and 366 nm – but faster decay at higher photon energy. Preliminary dissociation experiments at 355 nm did not reveal any major cleavage of the trimer 1 at the laser energies that were sufficient to cleave the monomer 4 at 266 nm. Because of this, the following experiments were performed

Photo-ignition process of multiwall carbon nanotubes and ferrocene by continuous wave Xe lamp illumination

• Paolo Visconti,
• Patrizio Primiceri,
• Daniele Longo,
• Luciano Strafella,
• Paolo Carlucci,
• Mauro Lomascolo,
• Arianna Cretì and
• Giuseppe Mele

Beilstein J. Nanotechnol. 2017, 8, 134–144, doi:10.3762/bjnano.8.14

• point of view, the suggested evolution of ignition process has been summarized in the Figure 17. As reported in Figure 17, the photo-induced process of charge separation, promoted by UV–vis–IR light irradiation (photon energy h∙ν = h∙c/λ with 380 nm < λ < 1000 nm, c speed of light and h Planck constant

Cubic chemically ordered FeRh and FeCo nanomagnets prepared by mass-selected low-energy cluster-beam deposition: a comparative study

• Veronique Dupuis,
• Anthony Robert,
• Arnaud Hillion,
• Ghassan Khadra,
• Nils Blanc,
• Damien Le Roy,
• Florent Tournus,
• Clement Albin,
• Olivier Boisron and
• Alexandre Tamion

Beilstein J. Nanotechnol. 2016, 7, 1850–1860, doi:10.3762/bjnano.7.177

• nanoparticles up to m = 12, our largest size. To go a step further in the investigation of the chemical ordering in FeCo, we used anomalous X-ray diffraction (AXD) in order to experimentally overcome the low “Z-contrast” between Fe and Co. This was achieved by changing the X-ray wavelength (or photon energy) by

• the absorption edge for heavy atoms [16]. From Figure 6, we found that a photon energy of 7.108 keV just before the Fe K absorption edge gave a maximum of anomalous contrast for the atomic scattering factor equal to nine for FeCo, larger than the atomic contrast (ΔZFeCo = 1). Thus, mass-selected 5 nm

• ″ coefficients as a function of photon energy for Fe, Co and Rh elements in the range of Fe and Co K edges. Measured X-ray scattering at 7.108 keV on annealed FeCo nanoparticles with 5 nm in diameter. (a) ZFC/FC and m(H) experimental data for mass-selected as-prepared FeCo clusters with 4.3 nm in diameter along

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

• thickness (the latter either increasing during an epitaxial process or diminishing during dry-etching). The current thickness of the etched layer can be determined in situ from single photon energy transients of just the average reflected intensity and, hence, any required etch depth can be achieved. Due to

• photon energy, the term RAS spectrum will be used. Due to the rotation of the substrates during epitaxy the software of the epitaxy-RAS instrumentation typically ignores the sign of the RAS signal. The time evolution of the spectrum of this RAS signal is called a false-color plot or short color plot (see

• techniques (as, e.g., reflection high-energy electron diffraction (RHEED)), which might not be applicable in some set-ups. Recording a RAS color plot is time-consuming, i.e., monitoring a single RAS spectrum from 1.5–5.0 eV photon energy with a step size of 0.1 eV during reactive ion etching (the substrate

Filled and empty states of Zn-TPP films deposited on Fe(001)-p(1×1)O

• Gianlorenzo Bussetti,
• Alberto Calloni,
• Rossella Yivlialin,
• Andrea Picone,
• Federico Bottegoni and
• Marco Finazzi

Beilstein J. Nanotechnol. 2016, 7, 1527–1531, doi:10.3762/bjnano.7.146

• ][26]. The IPES energy resolution is about 700 meV. All the experiments reported here were achieved under negligible charging conditions during electron spectroscopy data acquisition. The position of the vacuum level was obtained by adding the photon energy to the low-energy secondary electron cutoff

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

• , and with Equation 6, the relationship [(4πk/λ)hν]2 was determined as a function of the photon energy. Then, using the method of least squares, a linear function was fitted to the straight parts of the curves, showing the highest slope (Figure 11). The x-intercept of the fitted linear functions

• layers. The dependence (αhν)2 as a function of the photon energy. Left: the fit obtained from the UV–vis analysis (absorbance vs wavelength). Right: the fit obtained from ellipsometry analysis (extinction as a function of wavelength). The results of ellipsometric measurements of the thickness of the

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

• Figure 2. The fine structure of the absorption spectrum in the UV–vis region revealed upon background subtraction and ×100-fold magnification is represented by the grey curve in Figure 2a. One can observe an apparent double feature in the absorption spectrum in the photon energy region 1.5–3.5 eV, where

• the structure. The photon energy range from 2 to 3 eV is identified in the literature as the typical response of the luminescent extrinsic centers associated with surface defects or impurities introduced during the synthesis of the nanoparticles. In particular, the characteristic green luminescence at

The role of morphology and coupling of gold nanoparticles in optical breakdown during picosecond pulse exposures

• Yevgeniy R. Davletshin and
• J. Carl Kumaradas

Beilstein J. Nanotechnol. 2016, 7, 869–880, doi:10.3762/bjnano.7.79

• ]) since the photon energy at this time-scale is transferred to the electrons in the gold nanoparticle and diffusion is minimized [39][40]. The gold nanoparticles therefore retain their optical properties during LIB with pulses shorter than 10 ps. Compared to femtosecond lasers, ultrashort picosecond

Case studies on the formation of chalcogenide self-assembled monolayers on surfaces and dissociative processes

• Yongfeng Tong,
• Tingming Jiang,
• Azzedine Bendounan,
• Makri Nimbegondi Kotresh Harish,
• Angelo Giglia,
• Stefan Kubsky,
• Fausto Sirotti,
• Luca Pasquali,
• Srinivasan Sampath and
• Vladimir A. Esaulov

Beilstein J. Nanotechnol. 2016, 7, 263–277, doi:10.3762/bjnano.7.24

• resolution was 500 meV. The binding energy in the XPS spectra was calibrated with respect to the Au 4f7/2 peak, set at 84 eV. The calibration error is estimated to be 50 meV at TEMPO and about 100 meV at BEAR. With some exceptions (indicated later in the text), we used a photon energy corresponding to a

Impact of ultrasonic dispersion on the photocatalytic activity of titania aggregates

• Hoai Nga Le,
• Frank Babick,
• Klaus Kühn,
• Minh Tan Nguyen,
• Michael Stintz and
• Gianaurelio Cuniberti

Beilstein J. Nanotechnol. 2015, 6, 2423–2430, doi:10.3762/bjnano.6.250

• energy of the incident beam. In UV range, where radiation is adequate for TiO2 photocatalytic activation (appropriate for the photon energy of 3.2 eV and a wavelength of 387 nm [2][22][34][35]), the independence of transmittance as a function of the photocatalyst size is no longer valid as it is in the

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

• electron emission after APTES was deposited on the glass substrate and AuNPs were deposited on the APTES-functionalized glass substrate. The work function (Φ) can be calculated from the difference in the photon energy of He(I) (21.2 eV) and the energy difference ΔE between the secondary cut-off energy

Plasma fluorination of vertically aligned carbon nanotubes: functionalization and thermal stability

• Claudia Struzzi,
• Mattia Scardamaglia,
• Axel Hemberg,
• Luca Petaccia,
• Jean-François Colomer,
• Rony Snyders and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2015, 6, 2263–2271, doi:10.3762/bjnano.6.232

• surface during the measurements, a dual beam charge neutralization composed of an electron gun (≈1 eV) and an Ar ion gun (≤10 eV) was used. The valence band investigation was performed using an excitation photon energy of hν = 31 eV from a horizontally polarized (p-polarized) synchrotron light source at

• O 2p-like states and F 2p-like states are almost the same when using a photon energy of hν = 31 eV, it can be suggested that, when in high amounts, the structure generated by fluorine atoms prevails over that of oxygen-related states in valence band spectra. Fluorine atoms mainly bind to carbon

• . UPS spectra acquired with a photon energy of hν = 31 eV, the red line is the pristine vCNT sample, the blue is the functionalized, annealed (T = 300 °C) sample, the black and the green lines are related to samples heated at 500 and 900 °C, respectively. Raman spectra acquired on pristine

Influence of wide band gap oxide substrates on the photoelectrochemical properties and structural disorder of CdS nanoparticles grown by the successive ionic layer adsorption and reaction (SILAR) method

• Mikalai V. Malashchonak,
• Alexander V. Mazanik,
• Olga V. Korolik,
• Еugene А. Streltsov and
• Anatoly I. Kulak

Beilstein J. Nanotechnol. 2015, 6, 2252–2262, doi:10.3762/bjnano.6.231

• reprecipitation during the photocorrosion process. It should be noted that the oxide (ZnO, TiO2, In2O3)/CdS heterostructures are characterized by relatively high IPCE values of up to 60–90% at a photon energy of about 3 eV. This is due to the intimate contact of SILAR-deposited CdS nanoparticles with the

• NPs is reduced to hν due to weakening of the quantum-confinement effect. For this reason, at an early stage in the SILAR process, the signal intensity grows faster than the CdS amount. Due to the further weakening of the quantum-confinement effect in CdS nanoparticles, at larger N, the photon energy

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

• transmission through the dispersion as shown in Figure 2a. The optical limiting effect of the nanoparticles appears upon formation of microbubbles. The bubble formation occurs at the solvent–nanoparticle interface. The absorbed photon energy by the nanoparticle is dissipated as heat to the surrounding solvent

Characterization of nanostructured ZnO thin films deposited through vacuum evaporation

• Jose Alberto Alvarado,
• Arturo Maldonado,
• Héctor Juarez,
• Mauricio Pacio and
• Rene Perez

Beilstein J. Nanotechnol. 2015, 6, 971–975, doi:10.3762/bjnano.6.100

• transmittance by using Equation 1: where d is the thickness of the thin film, and T is measured transmission. In consequence, the relation between the coefficient and the photon energy for direct transition is , where A is a constant, Eg is the optical band gap, the plot of this relation has a linear region

Applications of three-dimensional carbon nanotube networks

• Manuela Scarselli,
• Paola Castrucci,
• Francesco De Nicola,
• Ilaria Cacciotti,
• Francesca Nanni,
• Emanuela Gatto,
• Mariano Venanzi and
• Maurizio De Crescenzi

Beilstein J. Nanotechnol. 2015, 6, 792–798, doi:10.3762/bjnano.6.82

• remove different types of oil has been demonstrated and can be considered very interesting for environmental applications. In addition, the CNT network shows a good photo response to incident light in the visible and near ultraviolet range, thus proving its potential application in photon-energy

Graphene quantum interference photodetector

• Mahbub Alam and
• Paul L. Voss

Beilstein J. Nanotechnol. 2015, 6, 726–735, doi:10.3762/bjnano.6.74

• % for the device. The results of the interaction of light with the zigzag and armchair structures are shown in Figure 5 and Figure 6, respectively. For this simulation, the parameters used for the zigzag structure were an applied voltage of 0.1 eV, photon energy of 0.26 eV and a photon flux of 1025

• photon/m2/s (4.16 × 106 W/m2). The parameters used for armchair structure were an applied voltage of 0.1 eV, photon energy of 0.13 eV and a photon flux of 1025 photon/m2/s (2.08 × 106 W/m2). For both the zigzag and armchair structures, the polarization of the applied electromagnetic field was along the

• variation of light. With the appropriate bias, the device can also be used to detect the photon energy corresponding to the energy difference of any two resonant levels. The peak photocurrent variations with different photon energies are shown in Figure 8a and Figure 8b corresponding to zigzag and armchair

Tm-doped TiO₂ and Tm₂Ti₂O₇ pyrochlore nanoparticles: enhancing the photocatalytic activity of rutile with a pyrochlore phase

• Desiré M. De los Santos,
• Javier Navas,
• Teresa Aguilar,
• Antonio Sánchez-Coronilla,
• Concha Fernández-Lorenzo,
• Rodrigo Alcántara,
• Jose Carlos Piñero,
• Ginesa Blanco and
• Joaquín Martín-Calleja

Beilstein J. Nanotechnol. 2015, 6, 605–616, doi:10.3762/bjnano.6.62

• determined by direct transition, or for n = 2 if the transition is indirect [18][19]. As the TiO2 band gap is determined by direct transition, the plot of [f(R)·hν]1/2 versus hν shows a linear region which satisfies the equation where hν is the photon energy, Eg is the band gap energy, and K a characteristic

Overview of nanoscale NEXAFS performed with soft X-ray microscopes

• Peter Guttmann and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2015, 6, 595–604, doi:10.3762/bjnano.6.61

• (i.e., up to 10 µm) specimens in materials and biological sciences using photon energies that covers the K- and L-X-ray absorption edges of elements of major interest [2][3][4][5]. High-photon energy X-ray diffraction used in operando studies can correlate changes in size of the unit cell of catalysts

• normally detect the photons which are transmitted through the sample. The penetration depth of X-rays and therefore the usable sample thickness correlates with the X-ray photon energy used for the analysis and is much larger than for electrons (Figure 2) [30]. In the soft X-ray regime penetration depths in

• the spatial resolution of the TXM, but still provide signals which can be used for NEXAFS spectroscopy. Spectroscopic studies at the carbon K-edge are very challenging because nearly in all beamlines the photon flux is sharply reduced within the carbon K-edge photon energy range (280 up to 320 eV) due

Structural, optical, opto-thermal and thermal properties of ZnS–PVA nanofluids synthesized through a radiolytic approach

• Alireza Kharazmi,
• Nastaran Faraji,
• Roslina Mat Hussin,
• Elias Saion,
• W. Mahmood Mat Yunus and
• Kasra Behzad

Beilstein J. Nanotechnol. 2015, 6, 529–536, doi:10.3762/bjnano.6.55

• concentration in agreement with the FTIR results. The optical band gap energy of the ZnS NPs was estimated through the Tauc equation as follows [6]: where α is the absorption coefficient, hν is the photon energy of the incident light, Eg is the band gap energy, B is a constant and n depends on the type of

Influence of size, shape and core–shell interface on surface plasmon resonance in Ag and Ag@MgO nanoparticle films deposited on Si/SiO_x

• Sergio D’Addato,
• Daniele Pinotti,
• Maria Chiara Spadaro,
• Guido Paolicelli,
• Vincenzo Grillo,
• Sergio Valeri,
• Luca Pasquali,
• Luca Bergamini and
• Stefano Corni

Beilstein J. Nanotechnol. 2015, 6, 404–413, doi:10.3762/bjnano.6.40

• radiation of s- and p-polarisation, together with classical electrodynamics simulations. For s-polarised incident radiation, it can be readily observed that SDR data from bare NPs do not reveal any significant features in the photon energy region between 2 and 4 eV (Figure 3b). In the case of MgO-covered

• . When co-deposited with Mg in O atmosphere, SEM images showed grains, which were assigned to formation of MgO shells around the original Ag NPs. SDR spectra taken under p-polarisation excitation exhibited a plasmon feature (with a deep minimum) at a photon energy between 3 and 3.5 eV where the intensity

Optical properties and electrical transport of thin films of terbium(III) bis(phthalocyanine) on cobalt

• Peter Robaschik,
• Pablo F. Siles,
• Daniel Bülz,
• Peter Richter,
• Manuel Monecke,
• Michael Fronk,
• Svetlana Klyatskaya,
• Daniel Grimm,
• Oliver G. Schmidt,
• Mario Ruben,
• Dietrich R. T. Zahn and
• Georgeta Salvan

Beilstein J. Nanotechnol. 2014, 5, 2070–2078, doi:10.3762/bjnano.5.215

• , respectively. For the dielectric constant we consider a minimum value of ε = 4.5, which is the real part of the dielectric function at the lowest photon energy (1.3 eV) used in our ellipsometry experiment (see Figure 2). As a maximum value for the dielectric constant we used ε = 13, which was previously

Cathode lens spectromicroscopy: methodology and applications

• T. O. Menteş,
• G. Zamborlini,
• A. Sala and
• A. Locatelli

Beilstein J. Nanotechnol. 2014, 5, 1873–1886, doi:10.3762/bjnano.5.198

• simplified sketch of an XPEEM setup is given in Figure 1a. Similar to LEEM, it is based on the cathode lens, which accelerates the photoelectrons to an energy of several keV and directs them towards the imaging column of the instrument. The low photon energy of the conventional photon sources readily

• secondary photoelectrons are collected in XPEEM as a close approximation to the total photoelectron yield measurement. The local XAS spectra are obtained by acquiring image sequences as a function of the photon energy, which can then be processed in order to extract the intensity variation within any region

• function. When the photon energy is tuned to the Fe absorption threshold (middle panel), the elongated Fe nanowires become much brighter, whereas the regions in between barely change intensity. The spectrum seen in the plot in Figure 3a is extracted from an individual nanowire. Magnetic imaging. X-ray

An insight into the mechanism of charge-transfer of hybrid polymer:ternary/quaternary chalcopyrite colloidal nanocrystals

• Parul Chawla,
• Son Singh and
• Shailesh Narain Sharma

Beilstein J. Nanotechnol. 2014, 5, 1235–1244, doi:10.3762/bjnano.5.137

• in Figure 3C(a–c), which shows the enhancement of the optical bandgap (as calculated from the Tauc’s plot involving the absorption coefficient, α and the photon energy hν) from CISe to CZTSe. The bandgap values of pristine CISe, CIGSe and CZTSe are ≈1.03 eV, 1.1 eV and 1.15 eV, respectively (Figure