Al₂O₃/TiO₂ inverse opals from electrosprayed self-assembled templates

• Arnau Coll,
• Sandra Bermejo,
• David Hernández and
• Luís Castañer

Beilstein J. Nanotechnol. 2018, 9, 216–223, doi:10.3762/bjnano.9.23

• , the reflectance of the fabricated samples has been measured over an area of 36 mm2 using a Fourier transform infrared (FTIR) spectrometer with an integrating sphere. We have conducted characterization measurements on the three steps of our process: (A) after step 1 in Figure 1a, (B) after step 3 in

• Figure 1c and (C) after step 4 in Figure 1d. The reflectance values as a function of the wavelength are shown in Figure 5. Looking to the plot corresponding to the measurement for step (A) related to the “polystyrene opal”, a broad peak of 81% reflectance located around 940 nm can be seen. The value of

• consistent with our measurements, and similar results are found elsewhere [37]. A secondary gap is also found centered at 470 nm wavelength. The measurements performed for step (B) that corresponds to the Al2O3 inverse opal are shown in Figure 5. A 72% reflectance peak centered at 686 nm and a secondary peak

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

• data in Figure 3, the transmittance achieves a level of 0.18, which is quite good regarding the absorbance of the microscope polarizers (ca. 65% of the incident non-polarized light) and reflectance of the chromium electrodes. While searching a fast and light efficient LC cell design, we have also

Facile synthesis of silver/silver thiocyanate (Ag@AgSCN) plasmonic nanostructures with enhanced photocatalytic performance

• Xinfu Zhao,
• Dairong Chen,
• Abdul Qayum,
• Bo Chen and
• Xiuling Jiao

Beilstein J. Nanotechnol. 2017, 8, 2781–2789, doi:10.3762/bjnano.8.277

• irradiated for 3 h, indicating the slow reduction of AgSCN under UV irradiation. UV–vis diffuse reflectance spectra of M0, M1, M2, M3, M4, and M5 are shown in Figure 2a. Here, the characteristic absorption of AgSCN appears at 200–350 nm and that from the surface plasmon resonance of Ag particles is above 350

• ) diffuse reflectance spectra (DRS) were recorded on an Agilent Cary 100 UV–vis spectrophotometer coupled to an integrating sphere with BaSO4 as reference. X-ray photoelectron spectra (XPS) were recorded on a Perkin-Elmer PHI-5300 ESCA spectrometer with a pass energy of 35.75 eV and an Al Kα line excitation

• -Elmer Lambda-35 UV–vis spectrometer. (a) XRD patterns of Ag@AgSCN nanostructures with different molar ratios of Ag to AgSCN. An (b) SEM image and (c) SAED pattern of the Ag@AgSCN nanostructure (sample M2). (a) UV–vis diffuse reflectance spectra of M0, M1, M2, M3, M4, M5. (b) Kubelka–Munk plots of M0 and

CdSe nanorod/TiO₂ nanoparticle heterojunctions with enhanced solar- and visible-light photocatalytic activity

• Fakher Laatar,
• Hatem Moussa,
• Halima Alem,
• Lavinia Balan,
• Emilien Girot,
• Ghouti Medjahdi,
• Hatem Ezzaouia and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2017, 8, 2741–2752, doi:10.3762/bjnano.8.273

• UV–visible spectrophotometer. Diffuse reflectance spectra (DRS) were recorded on a Shimadzu 2600 UV−visible spectrophotometer. BaSO4 powder was used as a standard for baseline measurements and spectra were recorded in a range of 250–1400 nm. Raman spectra were recorded using an Xplora spectrometer

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

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

• -illumination-mode optical microscopy images provides a rapid method to estimate the thickness of the exfoliated flakes at first glance. A quantitative analysis of the optical contrast spectra by means of micro-reflectance allows one to determine the refractive index of franckeite over a broad range of the

• values because they are the most common SiO2 thicknesses in the research of graphene and other 2D materials. Prior to the study of the optical properties of the franckeite nanosheets, we experimentally verify the thickness of the SiO2 capping layers of each employed substrate by means of reflectance

• determination. We use micro-reflectance spectroscopy to quantitatively characterize the optical contrast of franckeite flakes of different thicknesses transferred to SiO2/Si substrates [25][26]. The sample is illuminated in epi-illumination mode with the white light coming from the tungsten halogen lamp of a

Hydrothermal synthesis of ZnO quantum dot/KNb₃O₈ nanosheet photocatalysts for reducing carbon dioxide to methanol

• Xiao Shao,
• Weiyue Xin and
• Xiaohong Yin

Beilstein J. Nanotechnol. 2017, 8, 2264–2270, doi:10.3762/bjnano.8.226

• images were obtained with a Tecnai G2 F20 instrument. The UV–vis diffuse reflectance spectra were captured by a Shimadzu UV–2550 UV–vis spectrophotometer using BaSO4 as a reference in the wavelength region of 200–800 nm. Photoluminescence (PL) spectra were measured at room temperature on a Renishaw 1000

• reflectance spectra for different amounts of ZnO quantum dots loaded onto KNb3O8 nanosheets are illustrated in Figure 7. The steep absorption edge of the pure KNb3O8 nanosheets occurred around 343 nm under UV light owing to its large intrinsic band gap. When increasing the ZnO quantum dot loading, the sample

• % ZnO quantum dot/KNb3O8 nanosheet composite photocatalyst. (a) UV–vis diffuse reflectance spectra of the ZnO quantum dot/KNb3O8 nanosheet composite photocatalysts; (b) (αhv)1/2 versus the photon energy of the ZnO quantum dot/KNb3O8 nanosheet composite photocatalysts. Yield of methanol using KNb3O8

Bi-layer sandwich film for antibacterial catheters

• Gerhard Franz,
• Florian Schamberger,
• Hamideh Heidari Zare,
• Sara Felicitas Bröskamp and
• Dieter Jocham

Beilstein J. Nanotechnol. 2017, 8, 1982–2001, doi:10.3762/bjnano.8.199

• deposited layer (1,500 μm vs 0.3 μm), this method is hardly applicable. But recording the broad-band reflectance of the capillary will lead to success. We applied the spectrometer F20e from Filmetrics (Unterhaching, Germany) using a light spot with a diameter d of 30 μm. For a radius r of the capillary of

Growth and characterization of textured well-faceted ZnO on planar Si(100), planar Si(111), and textured Si(100) substrates for solar cell applications

• Chin-Yi Tsai,
• Jyong-Di Lai,
• Shih-Wei Feng,
• Chien-Jung Huang,
• Chien-Hsun Chen,
• Fann-Wei Yang,
• Hsiang-Chen Wang and
• Li-Wei Tu

Beilstein J. Nanotechnol. 2017, 8, 1939–1945, doi:10.3762/bjnano.8.194

• , and CL as well. The reflectance spectra of these three samples show that the antireflection function provided by theses samples mostly results from the nanometer-scaled texture of the ZnO films, while the micrometer-scaled texture of the Si substrate has a limited contribution. The results of this

• almost fully agrees with the CL intensity. Reflectance spectra The reflectance spectra of the three samples were measured, as shown in Figure 8. It shows that the difference in the reflectance spectra between the ZnOp(100) and ZnOp(111) samples is insignificant. The ZnOt(100) sample has smaller

• reflectance due to the additional texture provided by the micrometer-sized pyramid structure of the texture Si(100) substrate. Therefore, it could be concluded that the antireflection function provided by theses samples mostly results from the nanometer-sized texture of the ZnO films while the micrometer

Application of visible-light photosensitization to form alkyl-radical-derived thin films on gold

• Rashanique D. Quarels,
• Xianglin Zhai,
• Neepa Kuruppu,
• Jenny K. Hedlund,
• Ashley A. Ellsworth,
• Amy V. Walker,
• Jayne C. Garno and
• Justin R. Ragains

Beilstein J. Nanotechnol. 2017, 8, 1863–1877, doi:10.3762/bjnano.8.187

• irradiation all proved necessary for the deposition of robust films that could survive nanoshaving. In addition to characterizations with AFM, grazing angle infrared reflectance–absorbance spectroscopy (IRRAS), X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (TOF SIMS

• tips with an average spring constant of 0.6 N/m (Bruker Instruments, Camarillo, CA, USA). Digital images were processed with Gwyddion (v 2.30) software [53]. Grazing angle infrared reflectance absorbance spectroscopy (IRRAS): IRRAS spectra were recorded using a Bruker Tensor 27 instrument equipped with

Optical techniques for cervical neoplasia detection

• Tatiana Novikova

Beilstein J. Nanotechnol. 2017, 8, 1844–1862, doi:10.3762/bjnano.8.186

• biochemical properties of tissues. The different methods, including spectroscopic (diffuse reflectance spectroscopy, induced fluorescence and autofluorescence spectroscopy, Raman spectroscopy) and imaging techniques (confocal microscopy, optical coherence tomography, Mueller matrix imaging polarimetry

• such as diffuse reflectance spectroscopy, fluorescence spectroscopy, Raman spectroscopy, in vivo confocal microscopy, optical coherence tomography and multi-wavelength imaging Mueller polarimetry, as well as the combination of different techniques have been explored to improve the detection of cervical

• neoplasia. The results of these studies as well as current trends to miniaturization of diagnostic instruments will be discussed further. Optical spectroscopy and imaging In vivo diffuse reflectance optical spectroscopy (DRS) exploits the fact that abnormal zones of the cervical epithelium illuminated with

Uptake and intracellular accumulation of diamond nanoparticles – a metabolic and cytotoxic study

• Antonín Brož,
• Lucie Bačáková,
• Pavla Štenclová,
• Alexander Kromka and
• Štěpán Potocký

Beilstein J. Nanotechnol. 2017, 8, 1649–1657, doi:10.3762/bjnano.8.165

• prior to the grazing angle reflectance FTIR measurements. The optical absorbance was calculated in standard absorbance units as A = −log(R/R0), where R is the spectrum measured with NDs and R0 is the reference (background) spectrum recorded using the clean Au mirror before the NDs were applied. In all

Oxidative stabilization of polyacrylonitrile nanofibers and carbon nanofibers containing graphene oxide (GO): a spectroscopic and electrochemical study

• İlknur Gergin,
• Ezgi Ismar and
• A. Sezai Sarac

Beilstein J. Nanotechnol. 2017, 8, 1616–1628, doi:10.3762/bjnano.8.161

• morphological characterizations of the webs are carried out by using attenuated total reflectance Fourier transform infrared spectroscopy and Raman spectroscopy, scanning electron microscopy, atomic force microscopy and transmission electron microscopy. Mechanical tests are performed with a dynamic mechanical

• carbonization was performed at 900 °C for 1 h under nitrogen atmosphere. Characterization Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and Raman spectroscopy were used to record the characteristic peaks of the oxidized and carbonized nanofibers. Mechanical properties of

• reflectance Fourier transform infrared spectroscopy (ATR-FTIR) (Perkin Elmer, Spectrum One, with a Universal ATR attachment with a diamond and ZnSe crystal). The microstructure of the carbonized nanofiber webs was investigated by Raman spectroscopy (DXR Raman spectrometer, Thermo Scientific, at 532 nm). 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

Low-temperature CO oxidation over Cu/Pt co-doped ZrO₂ nanoparticles synthesized by solution combustion

• Amit Singhania and
• Shipra Mital Gupta

Beilstein J. Nanotechnol. 2017, 8, 1546–1552, doi:10.3762/bjnano.8.156

• ambient atmosphere. Raman spectra (100–750 cm−1) were obtained on a Horiba JY LabRAM HR 800 Raman spectrometer coupled with microscope in reflectance mode with 514 nm excitation laser sources and a spectral resolution of 0.3 cm−1. The amount of Cu and Pt in co-doped ZrO2 catalysts was confirmed using a

Oxidative chemical vapor deposition of polyaniline thin films

• Yuriy Y. Smolin,
• Masoud Soroush and
• Kenneth K. S. Lau

Beilstein J. Nanotechnol. 2017, 8, 1266–1276, doi:10.3762/bjnano.8.128

• a Thermo Nicolet 6700 spectrometer in transmission mode using an MCT/A detector at a resolution of 4 cm−1 and averaged over 128 scans. An FTIR spectrum of aniline monomer was also acquired in attenuated total reflectance (ATR) mode. Top-down SEM images were taken using a Zeiss Supra 50VP with the in

A top-down approach for fabricating three-dimensional closed hollow nanostructures with permeable thin metal walls

• Carlos Angulo Barrios and
• Víctor Canalejas-Tejero

Beilstein J. Nanotechnol. 2017, 8, 1231–1237, doi:10.3762/bjnano.8.124

• . This hollow metal configuration features optical resonance as revealed by spectral reflectance measurements and numerical simulations. The fabricated nanocages were demonstrated as a refractometric sensor with a measured bulk sensitivity of 327 nm/refractive index unit (RIU). The pattern design

• of arrays of closed cylindrical nanocages of Al on a Si substrate. In addition, relevant optical and sensing properties of the hollow configuration are studied by reflectance measurements and simulations. Results and Discussion Scanning electron microscope (SEM) photographs in Figure 1 illustrate the

• measured spectral reflectance of a 600 nm period, square lattice of SU-8 nanopillars fabricated on an Al-coated Si substrate (blue curve), the same structure after the deposition of a 40 nm thick Al film (red curve), and the latter structure after an oxygen-plasma treatment (black curve). As analyzed in a

ZnO nanoparticles sensitized by CuInZn_xS_2+x quantum dots as highly efficient solar light driven photocatalysts

• Florian Donat,
• Serge Corbel,
• Halima Alem,
• Steve Pontvianne,
• Lavinia Balan,
• Ghouti Medjahdi and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2017, 8, 1080–1093, doi:10.3762/bjnano.8.110

• spectrophotometer. The photoluminescence (PL) spectra were recorded on a Horiba Fluoromax-4 Jobin Yvon spectrofluorimeter. The diffuse reflectance spectra (DRS) were recorded on a Shimadzu 2600 UV–vis spectrophotometer. BaSO4 powder was used as a standard for baseline measurements and spectra were recorded in a

• photocatalyst. Supporting Information The Supporting Information contains UV–vis absorption, photoluminescence emission and diffuse reflectance spectra, Tauc plots, EDS analysis, XPS spectra, plots of ln(C0/C), an XRD pattern and an SEM image of the reused catalyst and the photocatalytic experiments in air

Optical response of heterogeneous polymer layers containing silver nanostructures

• Miriam Carlberg,
• Florent Pourcin,
• Olivier Margeat,
• Judikaël Le Rouzo,
• Gérard Berginc,
• Rose-Marie Sauvage,
• Jörg Ackermann and
• Ludovic Escoubas

Beilstein J. Nanotechnol. 2017, 8, 1065–1072, doi:10.3762/bjnano.8.108

• , transfer matrix method (TMM) calculations of the reflectance were compared with reflectance measurements carried out on a spectrophotometer (Lambda 950, PerkinElmer). It should be noted that the complex refractive index is , where n is the frequency-dependent real refractive index, and k is the frequency

• indices were then used to calculate the reflectance using a TMM calculation. The calculated reflectance was compared to the measured reflectance (Figure 3) in order to validate the mathematical laws used to model the thin film layer. With the fit quality optimized, the comparison between the measured and

• calculated reflectance is necessary to verify the physical validity of the fit. The two curves follow the same tendency. The slight discrepancy in the reflectance spectra could be attributed to the measurement or to diffusion phenomena induced by the NPs, which is not taken into account in our ellipsometry

High photocatalytic activity of Fe₂O₃/TiO₂ nanocomposites prepared by photodeposition for degradation of 2,4-dichlorophenoxyacetic acid

• Shu Chin Lee,
• Hendrik O. Lintang and
• Leny Yuliati

Beilstein J. Nanotechnol. 2017, 8, 915–926, doi:10.3762/bjnano.8.93

• the Fe(III) complex at 400 °C [5]. This is in contrast to the one prepared by the sol–gel method that showed an obviously reduced Eg value as the Fe ions were incorporated into the TiO2 lattice [7][19]. Diffuse reflectance (DR) UV–vis spectra and Tauc plots of the nanocomposites prepared by the

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

Investigation of the photocatalytic efficiency of tantalum alkoxy carboxylate-derived Ta₂O₅ nanoparticles in rhodamine B removal

• Subia Ambreen,
• Mohammad Danish,
• Narendra D. Pandey and
• Ashutosh Pandey

Beilstein J. Nanotechnol. 2017, 8, 604–613, doi:10.3762/bjnano.8.65

• . The distribution of particles is more uniform in the nanoparticles derived from carboxylato alkoxides than in those derived from alkoxides. UV–vis spectroscopy The optical properties of synthesized Ta2O5 nanoparticles were studied by UV–vis diffuse reflectance spectroscopy (DRS). The synthesized Ta2O5

• Ta2O5 synthesized from (a) Ta(On-Bu)4(OOCCH2Cl), (b) Ta(On-Bu)4(OOCCHCl2) and (c) Ta(On-Bu)4(OOCCCl3). Solid-state diffuse reflectance UV–vis spectrum and extrapolation of the band gap energy of Ta2O5 nanoparticles prepared from Ta(OEt)5. Degradation of RhB by Ta2O5 nanoparticles synthesized from (a) Ta

Graphene functionalised by laser-ablated V₂O₅ for a highly sensitive NH₃ sensor

• Margus Kodu,
• Artjom Berholts,
• Tauno Kahro,
• Mati Kook,
• Peeter Ritslaid,
• Helina Seemen,
• Tea Avarmaa,
• Harry Alles and
• Raivo Jaaniso

Beilstein J. Nanotechnol. 2017, 8, 571–578, doi:10.3762/bjnano.8.61

• observed as the result of the reaction of NH3 with two V2O5 adsorption sites, one with a surface OH group, forming positively charged NH4+, and the other with oxygen vacancy, forming species denoted as “coordinated NH3”. At the same time, the intensity of the V5+=O related band in the infrared reflectance

Thin SnO_x films for surface plasmon resonance enhanced ellipsometric gas sensing (SPREE)

• Daniel Fischer,
• Andreas Hertwig,
• Uwe Beck,
• Volkmar Lohse,
• Detlef Negendank,
• Martin Kormunda and
• Norbert Esser

Beilstein J. Nanotechnol. 2017, 8, 522–529, doi:10.3762/bjnano.8.56

• complex reflectance ratio ρ after irradiation of a sample with linear polarized light is measured. For a simple two-media dielectric interface, the complex reflectance ratio is given by [26][27] with rp,s as the Fresnel coefficent and δp,s as the phase for the p- and s-polarization state. tanΨ and Δ are

• intermediate layer is gold, the effect of the surface plasmon resonance has to be taken into account for the description of the reflection coefficients. Because this phenomenon effects mostly the reflection coefficient of the p-polarized part Rp, the SPR effect can be described by the reflectance = |Rp|2

• . Close to the surface plasmon resonance, the reflectance can be written as with kx0 as the component of the wave vector of the incident light in the direction of the surface plasmon propagation and kSP = + iΓ∞ as the wave vector of a surface plasmon on an interface of two semi-infinite media according

Fiber optic sensors based on hybrid phenyl-silica xerogel films to detect n-hexane: determination of the isosteric enthalpy of adsorption

• Jesús C. Echeverría,
• Ignacio Calleja,
• Paula Moriones and
• Julián J. Garrido

Beilstein J. Nanotechnol. 2017, 8, 475–484, doi:10.3762/bjnano.8.51

• , controlled porous texture that includes a specific surface area and average pore size distribution, and tunable surface chemistry. In the case of fiber optic reflectance sensors (FORSs), these sensitive films vary their optical properties upon interaction with the analyte, thereby resulting in a change in

• xerogel film covering the tip of the optical fiber, which acts as an optical cavity for which the fiber–xerogel provides the first interface and the xerogel–vapor provides the second interface. The reflectance of this sensing element may be expressed as follows [7][8][9]: In this equation, the

• the reflectance at the fiber–film interface and the sensor output signal. Furthermore, the reflectance is independent of temperature. The response of fiber optic sensors operating on reflection relies on the complex refractive index of the film and on the adsorption properties, which are related to