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

• was tested in water solution by monitoring the optical absorption changes in the presence of metal ions. A weak dependence of the peak wavelength as a function of the ion concentration was found. However, the large broadening of the SPR band and the high background of the absorption hindered the

• performed absorption measurements as a function of concentration of nickel ions. Figure 7a shows the optical absorption spectrum of the AgNP-3MPS solution with nickel for different ion concentrations in the range 1.0–0.1 ppm. Figure 7b presents the maximum wavelength of the absorption peak as a function of

Scanning probe microscopy studies on the adsorption of selected molecular dyes on titania

• Jakub S. Prauzner-Bechcicki,
• Lukasz Zajac,
• Piotr Olszowski,
• Res Jöhr,
• Antoine Hinaut,
• Thilo Glatzel,
• Bartosz Such,
• Ernst Meyer and
• Marek Szymonski

Beilstein J. Nanotechnol. 2016, 7, 1642–1653, doi:10.3762/bjnano.7.156

• low conversion efficiencies [1]. However, when the surface of a wide-band-gap material is covered with a sensitizer that absorbs light in the visible spectrum and enables charge transfer through the semiconductor–adsorbate interface, the situation changes dramatically. The optical absorption, and

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

• , electronic and photocatalytic properties have been investigated. Our results demonstrate that Ce-doping improves the optical absorption ability toward visible light wavelengths and thus the photocatalytic performances. ZnO:Ce rods allow the complete degradation of the Orange II dye in ca. 80 min under solar

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

• means of optical absorption and photoluminescence spectroscopy [25]. We have already reported elsewhere that the free-standing cubic HfO2 nanoparticles are luminescent on their own with characteristic emission in the blue-green region of the visible spectra. This may be attributed to surface defects

• nanotube structure, thus optical absorption and emission spectroscopy allow identification of the CNT chirality and diameter as well as quality in terms of nontubular carbon content and structural defects. The characterization of multiwalled CNTs, however, is challenging because of the involvement of

• several shells with different structure and typically higher defect concentration compared to single-walled CNTs. The optical absorption properties of the hybrid MWCNT:HfO2 nanocomposites deduced from the room temperature transmittance measurements of a colloidal suspension in ethanol are summarized in

Sandwich-like layer-by-layer assembly of gold nanoparticles with tunable SERS properties

• Zhicheng Liu,
• Lu Bai,
• Guizhe Zhao and
• Yaqing Liu

Beilstein J. Nanotechnol. 2016, 7, 1028–1032, doi:10.3762/bjnano.7.95

• sodium citrate solution was injected, as shown in Figure 1. The optical absorption peaks located at 520 and 532 nm indicate the strong surface plasmon resonance of the NPs. These uniform negatively charged citrate-protected Au NPs could be readily used in electrostatic LbL assembly. Typical sandwich-like

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

Selective photocatalytic reduction of CO₂ to methanol in CuO-loaded NaTaO₃ nanocubes in isopropanol

• Tianyu Xiang,
• Feng Xin,
• Jingshuai Chen,
• Yuwen Wang,
• Xiaohong Yin and
• Xiao Shao

Beilstein J. Nanotechnol. 2016, 7, 776–783, doi:10.3762/bjnano.7.69

• –precipitation mechanism, where the concentration of the NaOH solution played a crucial role on the morphology of the crystal. This was confirmed in our work. Figure 3 shows UV–vis diffuse reflectance spectra and optical absorption edges of NaTaO3 nanocubes prepared with different concentrations of NaOH. From

• isopropanol to methanol was also proposed and explained by band theory. XRD patterns of NaTaO3 nanocubes. SEM images of NaTaO3 nanocubes: (a) 1M-NaTaO3, (b) 2M-NaTaO3, (c) 3M-NaTaO3, and (d) 4M-NaTaO3. UV–vis diffuse reflectance spectra (a) and optical absorption band edges (b) of NaTaO3 nanocubes. XRD

Correlative infrared nanospectroscopic and nanomechanical imaging of block copolymer microdomains

• Benjamin Pollard and
• Markus B. Raschke

Beilstein J. Nanotechnol. 2016, 7, 605–612, doi:10.3762/bjnano.7.53

• the s-SNOM spectral phase in our analysis, which for weak molecular oscillators provides a good approximation of the spectral shape of the optical absorption or extinction coefficient [1]. Gaussian resonance curves are computationally fit to the spectra in order to extract peak position and

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

Efficiency improvement in the cantilever photothermal excitation method using a photothermal conversion layer

• Natsumi Inada,
• Hitoshi Asakawa,
• Taiki Kobayashi and
• Takeshi Fukuma

Beilstein J. Nanotechnol. 2016, 7, 409–417, doi:10.3762/bjnano.7.36

• cantilever geometry. As an alternative approach, the improvement of excitation efficiency using a short wavelength laser beam has been reported [27]. The high efficiency when using a short wavelength laser beam compared to a long wavelength laser beam is explained by the optical absorption characteristics of

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

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

• optical absorption and photocarrier recombination. The maximal IPCE values for the In2O3/CdS and ZnO/CdS heterostructures are attained at N ≈ 20, whereas for TiO2/CdS, the appropriate N value is an order of magnitude higher. The photocurrent and Raman spectroscopy studies of CdS nanoparticles revealed the

• , is non-monotonic and influenced by the competition of two processes: the increase in the optical absorption with N (i.e., with the amount of CdS) and the simultaneous enhancement of the recombination role due to the increased distance the photogenerated charge carriers must overcome. The number of N

• substrate, ensuring improved electron transfer from the NPs to the oxide matrix. For all types of WBGO substrates the dependence of IPCE (Y) on the number of SILAR cycles passes through a maximum (Figure 2d). The increase in IPCE in the range of small N is naturally related to the increase in optical

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

• ionic currents contribute to the absorption of the Ag2S QDs, which is affected by the pulse width waveforms. It could also be explained by an effect of nonlinear optical absorption that depends othe pump energy. This may reflect the dynamic behavior of gain or feedback mechanisms in the nonlinear

Current–voltage characteristics of manganite–titanite perovskite junctions

• Benedikt Ifland,
• Patrick Peretzki,
• Birte Kressdorf,
• Philipp Saring,
• Andreas Kelling,
• Michael Seibt and
• Christian Jooss

Beilstein J. Nanotechnol. 2015, 6, 1467–1484, doi:10.3762/bjnano.6.152

• , mixed halides. The constituents for manganite oxide are: A = rare earth, alkali metal, mixed composition, B = Mn, and X = O. The organic/inorganic halide perovskites exhibit good optical absorption and favorable electrical properties, thus offering the possibility for use in high efficiency solar cells

Electronic interaction in composites of a conjugated polymer and carbon nanotubes: first-principles calculation and photophysical approaches

• Florian Massuyeau,
• Jany Wéry,
• Jean-Luc Duvail,
• Serge Lefrant,
• Abu Yaya,
• Chris Ewels and
• Eric Faulques

Beilstein J. Nanotechnol. 2015, 6, 1138–1144, doi:10.3762/bjnano.6.115

• transfer between the polymer and the nanotubes is supported by examining steady-state PL energies of a series of composites films containing both metallic and SC nanotubes with x increasing from 0% to 64% compared to the optical absorption of SWNTs (Figure 5). We have substracted the absorption background

• of SWNTs which is due to the π plasmons. In this way, only the contribution of SC and metallic tubes is clearly displayed. These experiments show that there is substantial spectral overlap of PL and optical absorption of SWNTs which could, in principle, favor the occurrence of Förster energy transfer

Experimental determination of the light-trapping-induced absorption enhancement factor in DSSC photoanodes

• Serena Gagliardi and
• Mauro Falconieri

Beilstein J. Nanotechnol. 2015, 6, 886–892, doi:10.3762/bjnano.6.91

• , which therefore enhances the optical absorption. This approach describes a useful, functional characterization for the study of new morphologies of DSSC photoanodes. In fact, it can be applied both to simple structures and layered structures because it considers the photoanode as an effective layer and

Transformation of hydrogen titanate nanoribbons to TiO₂ nanoribbons and the influence of the transformation strategies on the photocatalytic performance

• Melita Rutar,
• Nejc Rozman,
• Matej Pregelj,
• Carla Bittencourt,
• Romana Cerc Korošec,
• Andrijana Sever Škapin,
• Aleš Mrzel,
• Srečo D. Škapin and
• Polona Umek

Beilstein J. Nanotechnol. 2015, 6, 831–844, doi:10.3762/bjnano.6.86

• light [23], compared with the undoped TiO2. The optical absorption spectrum of TN-580 (Figure S7, see Supporting Information File 1) shows that the sample absorbs light up to 500 nm, whereas TO-580 and CH-W do not. A comparison of the diffuse reflectance spectra of the N-doped TiO2 (not shown) reveals

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

• confirmed by powder X-ray diffraction in the 2θ range of 4 to 60° by using Philips X-ray diffractometer (7602 EA Almelo) with Cu Kα radiation (λ = 0.1542 nm). Optical absorption spectra were recorded by using a UV–vis spectrometer (Shimadzu-UV1650PC) in the wavelength range of 250 to 400 nm. The thermal

Palladium nanoparticles anchored to anatase TiO₂ for enhanced surface plasmon resonance-stimulated, visible-light-driven photocatalytic activity

• Kah Hon Leong,
• Hong Ye Chu,
• Shaliza Ibrahim and
• Pichiah Saravanan

Beilstein J. Nanotechnol. 2015, 6, 428–437, doi:10.3762/bjnano.6.43

• NPs can be distinguished by two peaks centered at binding energies of 334.3 eV and 340.0 eV, which are assigned to Pd 3d5/2, and Pd 3d3/2, respectively (Figure 6b) [48] and confirm the predominantly metallic form of the deposited noble metal. Optical absorption and photoluminescence The optical

Nanoporous Ge thin film production combining Ge sputtering and dopant implantation

• Jacques Perrin Toinin,
• Alain Portavoce,
• Khalid Hoummada,
• Michaël Texier,
• Maxime Bertoglio,
• Sandrine Bernardini,
• Marco Abbarchi and
• Lee Chow

Beilstein J. Nanotechnol. 2015, 6, 336–342, doi:10.3762/bjnano.6.32

• wavelengths (red–green). Si and Ge are indirect gap materials, requiring phonon scattering for optical absorption/emission to take place. However, Q-size effects present in porous semiconductors can promote optical transitions without the need of phonons by breaking the momentum conservation rules and/or by

Low-cost plasmonic solar cells prepared by chemical spray pyrolysis

• Erki Kärber,
• Atanas Katerski,
• Ilona Oja Acik,
• Valdek Mikli,
• Arvo Mere,
• Ilmo Sildos and
• Malle Krunks

Beilstein J. Nanotechnol. 2014, 5, 2398–2402, doi:10.3762/bjnano.5.249

• depth. However, longer wavelengths penetrate deeper into the absorber (or are transmitted) and hence can fully utilize the presence the Au-NPs on the rear side of the absorber. In addition, Au is also an excellent reflector for wavelengths greater than 600 nm. Furthermore, an increase in the optical

• absorption can be expected in the red/infrared region for the sprayed CIS/Au-NP composite layers, as previously shown [9][17]. The increase in the EQE is attributed to the increased CuInS2 coverage with Au-NPs when using a larger volume of the Au precursor solution [9]. The mean diameter of the individual

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

• to the optical transitions in amorphous TiO2 leading to enhanced optical absorption and, thus, generation of electron–hole pairs for photocatalysis (Figure 6a,b) [50]. Furthermore, plasmonic dye-sensitized solar cells based on Au@TiO2 nanostructures show remarkably enhanced power conversion

Hybrid spin-crossover nanostructures

• Carlos M. Quintero,
• Gautier Félix,
• Iurii Suleimanov,
• José Sánchez Costa,
• Gábor Molnár,
• Lionel Salmon,
• William Nicolazzi and
• Azzedine Bousseksou

Beilstein J. Nanotechnol. 2014, 5, 2230–2239, doi:10.3762/bjnano.5.232

• field around the metallic nanostructures can be successfully coupled to the molecular spin state changes brought on by the Fe centers of the SCO film. The LSPR technique was sensitive enough to detect the thermal spin transitions in thin films of up to 60 nm with a conventional optical absorption setup

Silicon and germanium nanocrystals: properties and characterization

• Ivana Capan,
• Alexandra Carvalho and
• José Coutinho

Beilstein J. Nanotechnol. 2014, 5, 1787–1794, doi:10.3762/bjnano.5.189

• surface groups was found to increase the electron binding energy of P, As and Sb, and to decrease the hole binding energy of B, Al, Ga and In [67]. Chlorine-covered Si NCs were found to have higher electron affinity, higher ionization energy and a lower optical absorption energy threshold than hydrogen

Growth evolution and phase transition from chalcocite to digenite in nanocrystalline copper sulfide: Morphological, optical and electrical properties

• Priscilla Vasthi Quintana-Ramirez,
• Ma. Concepción Arenas-Arrocena,
• José Santos-Cruz,
• Marina Vega-González,
• Omar Martínez-Alvarez,
• Víctor Manuel Castaño-Meneses,
• Laura Susana Acosta-Torres and
• Javier de la Fuente-Hernández

Beilstein J. Nanotechnol. 2014, 5, 1542–1552, doi:10.3762/bjnano.5.166

• is clear, that the deficiencies of copper generate a displacement or shift of the optical absorption, which is consistent to the transition of the phases. The energy band gaps of the samples were computed by the Tauc plot for direct transition (Figure 5). The indirect plot (inset) did not present a

• thin films from an aqueous solution [25][37]. On the other hand, the direct Eg values of the CuxS samples prepared in the organic solvent are in the range of 1.57–1.87 eV. These values are adequate for an optical absorption in the visible region, which makes the samples very promising materials for