Thickness-dependent photoelectrochemical properties of a semitransparent Co₃O₄ photocathode

• Malkeshkumar Patel and
• Joondong Kim

Beilstein J. Nanotechnol. 2018, 9, 2432–2442, doi:10.3762/bjnano.9.228

• photoelectrochemical cell properties. Figure 2a shows the thickness-dependent transmittance (T) and absorbance (A) spectra of the Co3O4 samples. Interestingly, all the Co3O4 samples exhibited fair absorbance with semitransparent optical properties. Absorbance dominates the shorter wavelengths (λ = 300–500 nm) with

• transmittance dominating at longer wavelengths from 600 nm to the infrared (IR). Two distinct transitions in both the T and A spectra of all Co3O4 samples are attributed to two bandgaps coexisting in the Co3O4 material. A 70 nm thick Co3O4 sample exhibited a higher T in the IR region than the other Co3O4

• out using a UV–visible spectrophotometer (Shimadzu, UV-2600) by recording the transmittance, absorbance, and reflection of the Co3O4 films in the range of 300–1100 nm. Photoelectrochemical cell measurements: Photoelectrochemical measurements were performed in a three-electrode cell with a potentiostat

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

Light extraction efficiency enhancement of flip-chip blue light-emitting diodes by anodic aluminum oxide

• Yi-Ru Huang,
• Yao-Ching Chiu,
• Kuan-Chieh Huang,
• Shao-Ying Ting,
• Po-Jui Chiang,
• Chih-Ming Lai,
• Chun-Ping Jen,
• Snow H. Tseng and
• Hsiang-Chen Wang

Beilstein J. Nanotechnol. 2018, 9, 1602–1612, doi:10.3762/bjnano.9.152

• transmittance of 440–450 nm. However, AAO80 has wider transmittance windows than other samples. Figure 10b shows that transmittance drastically decreases when Al is present in the sample structure. The thickness of Al in the form of Al2O3 is less than 10 nm. Figure 10c shows the modified absorption result for

• Al after the refractive index of the imaginary part (absorption) has been multiplied by 0.01, that is, the artificial absorption of Al has decreased by 100 times. In this condition, the transmittance of the modified Al absorption is still lower than without Al calculations. This type of calculation

• result indicates reasonable physics. Extremely low transmittance exists when the thickness of Al is approximately 790–590 nm. We redesigned the sample structure with different Al thicknesses in reference to the TEM results. We adjusted the thickness of Al2O3 as shown in Figure 11 to meet the different

Tailoring polarization and magnetization of absorbing terahertz metamaterials using a cut-wire sandwich structure

• Hadi Teguh Yudistira,
• Shuo Liu,
• Tie Jun Cui and
• Han Zhang

Beilstein J. Nanotechnol. 2018, 9, 1437–1447, doi:10.3762/bjnano.9.136

• Discussion The absorbance (A(ω)) of the material was calculated from the reflectance (R(ω)) and transmittance (T(ω)) by using the following equation: A(ω) = 1 − R(ω) − T(ω). Smith et al. [36] defined transmittance and reflectance as and Where t(ω), r(ω), n, k0, d and z are the transmissivity, reflectivity

• . Equation 3 can be simplified as Equation 4 shows that a high imaginary refractive index is required to achieve zero transmittance. To achieve high absorbance, the impedance of the metamaterial should match the air impedance and the imaginary part of the refractive index value should be high. The electrical

• × 1015 s−1. ω, ωp,Au and ΓAu are the angular frequency, angular plasma frequency of gold, and damping constant of gold, respectively. Figure 3 presents the reflectance–transmittance–absorbance (RTA) simulation result of cut-wire (Figure 3a), cross-shaped (Figure 3b) and star-shaped sandwich structures

Nanoporous silicon nitride-based membranes of controlled pore size, shape and areal density: Fabrication as well as electrophoretic and molecular filtering characterization

• Axel Seidenstücker,
• Stefan Beirle,
• Fabian Enderle,
• Paul Ziemann,
• Othmar Marti and
• Alfred Plettl

Beilstein J. Nanotechnol. 2018, 9, 1390–1398, doi:10.3762/bjnano.9.131

• ] is between the previous two. Thus, the observed transmittance through the membrane is expected. However, the reduced intensity rate and the shape of the intensity-versus-time curve indicating intermediate restriction steps confirm the general experience “that diffusion may be greatly restricted

Interplay between pairing and correlations in spin-polarized bound states

• Szczepan Głodzik,
• Aksel Kobiałka,
• Anna Gorczyca-Goraj,
• Andrzej Ptok,
• Grzegorz Górski,
• Maciej M. Maśka and
• Tadeusz Domański

Beilstein J. Nanotechnol. 2018, 9, 1370–1380, doi:10.3762/bjnano.9.129

• STM tip and the superconducting substrate, inducing a charge transport that, in a subgap regime () originates from the Andreev (particle to hole) scattering mechanism. The polarized Andreev current can be expressed by the Landauer–Büttiker formula where transmittance is defined as and The anomalous

Semi-automatic spray pyrolysis deposition of thin, transparent, titania films as blocking layers for dye-sensitized and perovskite solar cells

• Hana Krýsová,
• Josef Krýsa and
• Ladislav Kavan

Beilstein J. Nanotechnol. 2018, 9, 1135–1145, doi:10.3762/bjnano.9.105

• nm for FTO(A), but between 300 and 500 nm for FTO(B). Furthermore, FTO(B) is less transparent than FTO(A), whereby the optical transmittance in the range of wavelengths from 350 to 550 nm is by about 15–20% lower, which is consistent with the difference in the structure. The coherent domain size

Comparative study of antibacterial properties of polystyrene films with TiO_x and Cu nanoparticles fabricated using cluster beam technique

• Vladimir N. Popok,
• Cesarino M. Jeppesen,
• Peter Fojan,
• Anna Kuzminova,
• Jan Hanuš and
• Ondřej Kylián

Beilstein J. Nanotechnol. 2018, 9, 861–869, doi:10.3762/bjnano.9.80

• transmittance measurements presented in Supporting Information File 1. In-flight oxidation (type 3) results in an increase of the contribution of titanium oxide compounds. Namely, the band of TiO2 (IV) becomes the most intense one in the spectra (Figure 4b). The fraction of metallic compound is found to be less

Electron interaction with copper(II) carboxylate compounds

• Michal Lacko,
• Peter Papp,
• Iwona B. Szymańska,
• Edward Szłyk and
• Štefan Matejčík

Beilstein J. Nanotechnol. 2018, 9, 384–398, doi:10.3762/bjnano.9.38

• . High resolution measurements presented in the paper represent a peak FWHM ≈0.6 amu and for medium resolution ≈1.6 amu. Measurements with low and very low resolution yield FWHM of peaks ≈4.5 both, however with higher transmittance for the second one. (Regular m/Δm ratio can be hardly evaluated due to

Nematic liquid crystal alignment on subwavelength metal gratings

• Irina V. Kasyanova,
• Artur R. Geivandov,
• Vladimir V. Artemov,
• Maxim V. Gorkunov and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2018, 9, 42–47, doi:10.3762/bjnano.9.6

• , Russia 10.3762/bjnano.9.6 Abstract We have studied the alignment of a nematic liquid crystal (LC) material on aluminum subwavelength nanogratings as a function of the period, p, and the slit width to period ratio, w/p. A method, based on Fourier analysis of the transmittance spectra of the LC grating

• , which involves the ion-beam milling technique and assembly of the experimental liquid crystal cell. The second section is dedicated to data analysis, where besides polarized microscope observations, we apply the Fourier transform technique to the transmittance spectra in order to extract the effective

• crossed polarizers with the sample axis at 45° to the polarizer axis (P1 and P2, Figure 3a) all the gratings and reference squares are bright. They provide different phase retardation and transmittance spectra as observed by their different colors in Figure 3. Moreover, in some cases, different colors are

Study of the vertically aligned in-plane switching liquid crystal mode in microscale periodic electric fields

• Artur R. Geivandov,
• Mikhail I. Barnik,
• Irina V. Kasyanova and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2018, 9, 11–19, doi:10.3762/bjnano.9.2

• . From the oscillograms in Figure 2, the grayscale performance (transmittance vs voltage) plot shown in Figure 3 can be derived. Almost triple voltage is required to reach the saturation level for ZLI 1957/5 LC cell compared to E7. While the E7 LC cell is operable at driving voltage amplitudes lower than

• 6 V, the ZLI 1957/5 LC cell requires up to 20 V to reach the maximal transmittance. The maximal transmittance achieved in the of ZLI 1957/5 LC cell is a few percent higher than that in the E7 cell. There are three reasons for this phenomenon: The first reason is related to the higher refractive

• index modulation is higher in the E7 LC cell, which can result in higher light leakage into the first and higher diffraction orders. The impact of the diffraction can also explain the higher values of transmittance we obtained by numerical simulations (see below in Figure 12) in comparison with the

Enhanced photoelectrochemical water splitting performance using morphology-controlled BiVO₄ with W doping

• Xin Zhao and
• Zhong Chen

Beilstein J. Nanotechnol. 2017, 8, 2640–2647, doi:10.3762/bjnano.8.264

• nanostructured W-doped BiVO4 in comparison with the planar structure, two representative samples with planar and nanoporous structure, 0-water and 1-EG, were selected. Figure 4 shows the light absorption efficiency of the samples 0-water and 1-EG by measuring the light transmittance and reflectance [12]. The

• °. Elemental analysis was conducted by energy-dispersive X-ray spectroscopy (EDX) equipped on a field-emission scanning electron microscopy (FESEM, JEOL JSM-7600F). Light absorption was measured using a UV–visible spectrophotometer by measuring the reflectance and transmittance with an integrating sphere

The role of ligands in coinage-metal nanoparticles for electronics

• Ioannis Kanelidis and
• Tobias Kraus

Beilstein J. Nanotechnol. 2017, 8, 2625–2639, doi:10.3762/bjnano.8.263

• interface, and transferred to a substrate by using a Langmuir–Blodgett trough. The single-layer nanomembrane that formed on the water surface had excellent optical transmittance of 90–97% and an electrical resistance of 1.14 × 106 Ω/sq; it reacted to mechanical bending with a 14% increase in resistance

Refractive index sensing and surface-enhanced Raman spectroscopy using silver–gold layered bimetallic plasmonic crystals

• Somi Kang,
• Sean E. Lehman,
• Matthew V. Schulmerich,
• An-Phong Le,
• Tae-woo Lee,
• Stephen K. Gray,
• Rohit Bhargava and
• Ralph G. Nuzzo

Beilstein J. Nanotechnol. 2017, 8, 2492–2503, doi:10.3762/bjnano.8.249

• changes has been previously shown to be better for the full-3D PC structure as compared with the quasi-3D counterpart, the transmittance spectra for the former over a range of 355–1000 nm were collected as a function of time while PEG solutions of different concentration (from 1.4 to 5.6 wt %) were passed

• features at frequencies in the visible range (wavelengths spanning 600–800 nm). From the transmittance measurements made in air (shown in Figure 1e), we can further infer that the shifts of peak maxima that occur as a result of changes made in the metal overlayer composition are small if nanohole

• , corresponds to the case for the noted modes of benzenethiol where the PC provides maximal transmittance at wavelengths of 821 nm and 840 nm (the halfway point between λex and λRaman). The experimental transmission spectra of Au50 and Ag40Au10 quasi-3D PCs measured in air shown in Figure 4b qualitatively

Optical contrast and refractive index of natural van der Waals heterostructure nanosheets of franckeite

• Patricia Gant,
• Foad Ghasemi,
• David Maeso,
• Carmen Munuera,
• Elena López-Elvira,
• Riccardo Frisenda,
• David Pérez De Lara,
• Gabino Rubio-Bollinger,
• Mar Garcia-Hernandez and
• Andres Castellanos-Gomez

Beilstein J. Nanotechnol. 2017, 8, 2357–2362, doi:10.3762/bjnano.8.235

• of the exfoliated flakes can be obtained from the quantitative analysis of the transmission-mode images, acquired on the Gelfilm carrier substrate prior to the transfer. Figure 3 shows the transmittance extracted from the red, green and blue channel of the digital images where a monotonic thickness

• onto a 92 nm SiO2/Si substrate. Below (d) to (f) the colour chart shows a coarse guide to determine the thickness of franckeite flakes on 92 nm SiO2/Si substrates through their apparent colour. Thickness dependence of the transmittance acquired from transmission-mode optical images of franckeite flakes

High-stress study of bioinspired multifunctional PEDOT:PSS/nanoclay nanocomposites using AFM, SEM and numerical simulation

• Alfredo J. Diaz,
• Hanaul Noh,
• Tobias Meier and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 2069–2082, doi:10.3762/bjnano.8.207

• nacre-mimetics by designing an optically transparent and electron conductive coating based on PEDOT:PSS and nanoclays Laponite RD and Cloisite Na+. We carry out extensive characterization of the nanocomposite using transmittance spectra (transparency), conductive atomic force microscopy (conductivity

• characterized using optical transmittance spectroscopy. Nanocomposites prepared from Laponite RD (LAP) and Cloisite Na+ (montmorillonite, MTM) were also compared to the bare PEDOT:PSS to evaluate the change in transmittance caused by the addition of nanoclay. Figure 1a demonstrates the tunability of the

• nanocomposites’ transparency by changing the thickness. The samples are casted onto glass substrates and the grey dashed line represents the transmittance across the bare substrate. The trend shows that, as the thickness decreases, more light is transmitted, i.e., the transmittance approaches the value of the

Two-dimensional carbon-based nanocomposites for photocatalytic energy generation and environmental remediation applications

• Suneel Kumar,
• Ashish Kumar,
• Ashish Bahuguna,
• Vipul Sharma and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2017, 8, 1571–1600, doi:10.3762/bjnano.8.159

• high transparency, high elastic modulus (≈1 TPa), high mechanical strength (≈1060 GPa), and optical transmittance (≈97.7%) [44]. These superior properties of graphene make it a potential candidate for technological application such as such as optical electronics [45], photosensors [46] and

Growth, structure and stability of sputter-deposited MoS₂ thin films

• Reinhard Kaindl,
• Bernhard C. Bayer,
• Roland Resel,
• Thomas Müller,
• Viera Skakalova,
• Gerlinde Habler,
• Rainer Abart,
• Alexey S. Cherevan,
• Dominik Eder,
• Maxime Blatter,
• Fabian Fischer,
• Jannik C. Meyer,
• Dmitry K. Polyushkin and
• Wolfgang Waldhauser

Beilstein J. Nanotechnol. 2017, 8, 1115–1126, doi:10.3762/bjnano.8.113

• found to have a direct bandgap of ≈1.8 eV [8]. Relatively high mechanical flexibility, good optical transmittance, high current on/off ratios in field effect transistor (FET) geometries and reasonably good field effect mobilities make atomically thin MoS2 layers a promising candidate for flexible and

Study of the correlation between sensing performance and surface morphology of inkjet-printed aqueous graphene-based chemiresistors for NO₂ detection

• F. Villani,
• C. Schiattarella,
• T. Polichetti,
• R. Di Capua,
• F. Loffredo,
• B. Alfano,
• M. L. Miglietta,
• E. Massera,
• L. Verdoliva and
• G. Di Francia

Beilstein J. Nanotechnol. 2017, 8, 1023–1031, doi:10.3762/bjnano.8.103

• account the filter mass. UV–vis (200–850 nm) transmittance spectra of a diluted set of this dispersion have been performed by means of a Shimadzu UV-1800 UV–vis spectrophotometer. In all cases, UV–vis absorbance spectra have been measured that appeared flat and featureless [5]. The absorption coefficient

Nanoantenna-assisted plasmonic enhancement of IR absorption of vibrational modes of organic molecules

• Alexander G. Milekhin,
• Olga Cherkasova,
• Sergei A. Kuznetsov,
• Ilya A. Milekhin,
• Ekatherina E. Rodyakina,
• Alexander V. Latyshev,
• Sreetama Banerjee,
• Georgeta Salvan and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2017, 8, 975–981, doi:10.3762/bjnano.8.99

• , corresponding to only 145 molecules per antenna [20]. A similar approach is used for the terahertz (or far-IR) spectral range for which special nanoscale slot-antenna arrays were designed to determine glucose and fructose in solutions, including market beverages [21]. Terahertz transmittance measurements were

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

• excellent thermal (≈5000 W·m−1·K−1) [6] and electrical conductivity (up to 6000 S·cm−1) [7] and high theoretical specific surface area (2630 m2·g−1) [8]. Graphene is highly optically transparent (transmittance ≈97.7%) with absorption of <2.3% for visible light [9] and negligible reflectance (<0.1

• comparable sheet resistances and optical transmittance. A few drawbacks of Cu NW films, such as low oxidation resistance or weak adhesion to the substrate, can be compensated for by the addition of graphene. The resulting hybrid films have improved electrical conductivity as they provide 2D pathways for

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

• deflection spectroscopy (PDS), a technique for measuring weak optical absorption in thin films [14][28]. Unlike optical transmittance spectroscopy, PDS detects directly the amount of the absorbed light by measuring the heat generated by the optical absorption with the optical absorptance sensitivity down to

• influence of the optical scattering, which is important in the case of ZnO nanocolumns for which the transmittance spectra are significantly deteriorated by optical scattering. Cross-sectional (a) and top (b) view of densely packed ZnO NCs grown at 90 °C for 180 min (scale bar: 500 nm). High-resolution core

Fabrication of black-gold coatings by glancing angle deposition with sputtering

• Alan Vitrey,
• Rafael Alvarez,
• Alberto Palmero,
• María Ujué González and
• José Miguel García-Martín

Beilstein J. Nanotechnol. 2017, 8, 434–439, doi:10.3762/bjnano.8.46

• transmittance measurements have been performed using unpolarized light with almost normal incidence in the VIS–nIR range and an Andor Shamrock spectrometer. Results and Discussion Figure 2a shows a photograph of two samples prepared onto Si(001) substrates with 1 cm2 area: the one on the left was prepared with

• , whereas the nanostructured sample shows a much darker color. Their optical spectra are shown in Figure 5b. The transmittance (T) and the reflectance (R) have been measured directly, whereas the absorption (A) has been deduced taken into account that T + R + A = 1 (strictly speaking, in the nanostructured

• nanostructured Au sample prepared with σ = 85° (right). (b) Transmittance, reflectance and absorption spectra of those samples. Acknowledgements The authors thank MINECO (Projects MAT2014-59772-C2-1, MAT2015-69035-REDC) for financial support.

Optical and photocatalytic properties of TiO₂ nanoplumes

• Viviana Scuderi,
• Massimo Zimbone,
• Maria Miritello,
• Giuseppe Nicotra,
• Giuliana Impellizzeri and
• Vittorio Privitera

Beilstein J. Nanotechnol. 2017, 8, 190–195, doi:10.3762/bjnano.8.20

• , and as a consequence could favor the photocatalytic activity. In order to gain more insight into the realized structure, we performed transmittance (T) and reflectance (R) measurements in the range of 200–800 nm. The optical spectra are reported in Figure 4. The transmittance spectra (Figure 4a) show

• that the transmitted light by the samples is closely related to the thickness of the residual Ti layer and, consequently, to the etching time. In fact, for a fixed Ti starting thickness we observed a more efficient transmittance after longer etching times (compare the dashed-dotted with the dotted line

• constant, and the low-frequency dielectric constant tabulated for titanium. The refractive index of titanium is calculated by the square root of Equation 1 [26]: The refractive index of the TiO2 film was extracted by fitting both the reflectance and transmittance spectra of the Ti (430-190) sample, by

Nitrogen-doped twisted graphene grown on copper by atmospheric pressure CVD from a decane precursor

• Ivan V. Komissarov,
• Nikolai G. Kovalchuk,
• Vladimir A. Labunov,
• Ksenia V. Girel,
• Olga V. Korolik,
• Mikhail S. Tivanov,
• Algirdas Lazauskas,
• Mindaugas Andrulevičius,
• Tomas Tamulevičius,
• Viktoras Grigaliūnas,
• Šarunas Meškinis,
• Sigitas Tamulevičius and
• Serghej L. Prischepa

Beilstein J. Nanotechnol. 2017, 8, 145–158, doi:10.3762/bjnano.8.15

• procedure was applied. Finally, the transmittance was measured using the PROSCAN MC-121 spectrometer. Results The optical images of samples A and B on copper foil are shown in Figure 1a and Figure 1b, respectively. The surface of sample A contains randomly distributed hexagonally shaped spots (brighter

• (≈50%), which helps to evaluate and compare the structural properties of SLG and TG. However, for other sets of data, the fraction of double layer TG dominates. We also proved homogeneity directly by the light transmittance measurement of samples transferred on a glass substrate. The diameter of probed

• area was ≈0.5 cm. In Figure 12 we show the transmittance for sample B recorded in the 400–800 nm range. It follows that the transmittance at 550 nm is 94%. This value corresponds to a number of graphene layers between 2 (95.5%) and 3 (93.3%) [26]. It is worth mentioning that the twisted nature of