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Anti‐reflection (AR) characteristics on the display surface and light outcoupling efficiency are significant factors for controlling external and internal light in organic light‐emitting diodes (OLEDs), respectively. This paper presents the fabrication of moth‐eye nanostructured parylene‐C films that simultaneously achieve optimized AR characteristics and enhanced OLED performance. AR performance is optimized by varying the nanostructure dimensions, resulting in a nanostructured film with a reflectance of <1%. Furthermore, applying this nanostructured film to OLEDs improved the light outcoupling efficiency by 40% compared with the reference device. Therefore, employing nanostructured parylene‐C films to enhance the optical characteristics of OLEDs is proposed. [ABSTRACT FROM AUTHOR]

Epoxy-acrylate (EA) core–shell nanoparticles have gained significant attention recently due to their dual unique properties as heterogeneous materials, particularly in coating applications. However, the effect of epoxy (EP) concentration in core layer on mechanical properties is still limited, and the mechanism of how it affects the film's performance is not well understood. In this study, we investigate the effect of varying EP concentration in the core layer on the mechanical properties of nanostructured films containing EA core–shell nanoparticles. The core–shell nanoparticles were synthesized through multistage seeded emulsion polymerization. The transmission electron microscopy (TEM) images revealed similar particle morphology and size in all EA nanoparticles. Differential scanning calorimetry (DSC) analysis confirmed the successful synthesis of core–shell particle morphology with two glass transition temperature (Tg) values (~12 °C and ~ 60 °C) observed for the core and shell layers, respectively. We observed an increase in the Tg values of the shell layer with higher EP content in the core layer. The use of EP-based copolymers raised the Tg values of the shell layer, significantly affecting the film formation behavior and their mechanical properties through interlayer crosslinking. Tensile modulus values for the films ranged from 200 to 500 MPa, marking the highest modulus reported for cast films of EA nanostructured films. Our findings reveal a straightforward and versatile method for producing high-modulus EA nanostructured films with customizable mechanical properties, making the model ideal for enhancing wood coating performance. [ABSTRACT FROM AUTHOR]

Abstract Anti‐reflection (AR) characteristics on the display surface and light outcoupling efficiency are significant factors for controlling external and internal light in organic light‐emitting diodes (OLEDs), respectively. This paper presents the fabrication of moth‐eye nanostructured parylene‐C films that simultaneously achieve optimized AR characteristics and enhanced OLED performance. AR performance is optimized by varying the nanostructure dimensions, resulting in a nanostructured film with a reflectance of

Copper-doped cadmium sulfide (CdS:Cu) nanocrystalline thin films were coated on glass substrates with different Cu concentrations (0 wt.%, 3 wt.%, and 6 wt.%) using the sol–gel spin coating technique. X-ray diffraction (XRD) spectrometry, scanning electron microscope (SEM), and energy-dispersive X-ray (EDX) analysis were used to analyze the average crystallite size, surface morphology, and chemical analysis of prepared thin films in 3 and 6 wt.% of Cu concentrations. According to the XRD results and SEM micrographs, nanocrystalline grains of doped thin films have an almost regular geometric shape, which become slightly larger by increasing Cu concentration from 3 to 6 wt.%. The optical and electrical characteristics of all three films were examined by spectroscopy ellipsometry (SE) technique in the wavelength range between 300 and 900 nm. Based on the SE results, the thin film prepared with 0 wt.% Cu concentration showed a higher refractive index, extinction coefficient, and absorbance compared to the other Cu-doped thin films. The CdS:Cu thin films with 3 and 6 wt.% Cu concentrations demonstrated significantly higher transparency than pure ones (0 wt.% Cu doped), making them particularly suitable for different optoelectronic applications. Moreover, the optical band gap energy (Eg) values were evaluated. It can be concluded that the pure film has the largest band gap energy, and Cu doping reduces the Eg values. The spin-coated 6 wt.% CdS:Cu thin film showed high transparency (67.83%), good homogeneity, and a substantial Eg value (2.6 eV), making it ideal for photocatalytic and photovoltaic applications. [ABSTRACT FROM AUTHOR]

Early diagnosis of cattle diseases such as mastitis caused by Staphylococcus aureus (S. aureus) can be made effective if on-site detection methods with portable instruments are available. In this work, we fabricated immunosensors based on a layer-by-layer (LbL) film of chitosan and carbon nanotubes coated with a layer of antibodies to detect S. aureus. Using electrical and electrochemical impedance spectroscopies, detection was possible in buffer solutions and in milk with limits of detection which could be as low as 2.6 CFU/mL for milk, sufficient to detect mastitis at early stages. This high sensitivity is ascribed to the specific interactions involving the antibodies, as demonstrated with polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS). The selectivity of the immunosensor was verified by distinguishing S. aureus-containing samples from possible interferents found in milk, for which the interactive document mapping (IDMAP) was employed. Because the interferents affected the spectra, in spite of this distinguishability, we treated the data with a machine learning technique with decision tree models. A multidimensional calibration space was then obtained with rules that permit interpretability and predictability in detecting S. aureus in matrices with high variability as in milk.

The characteristic energies of elementary excitations and collective modes in many quantum materials lie mostly in the terahertz (THz) frequency range, which provides a wide space for the development of THz optical materials and devices. In particular, topological Weyl semimetal Mn3Sn is a noncollinear antiferromagnet with anomalous THz properties, which is strongly affected by thermal energy and external magnetic fields. Despite the explosive growth of the research on magnetic Weyl semimetals recently, its nanoscale structure for applications in THz optical devices remains to be explored. Here, we fabricated nanostructured Mn3+0.53Sn films with different crystal orientations, driven by Ostwald Ripening (OR) on (0001) c-Al2O3. A huge anisotropic THz response manifested a firm link between the optical properties of Weyl antiferromagnet Mn3Sn and its contrivable spin structures. The topological properties of Mn3Sn are robustly protected in its nanostructures. This work can provide a new horizon for the fabrication of a nanostructured magnetic Weyl alloy and for its potential applications in subwavelength high-performance THz devices. [ABSTRACT FROM AUTHOR]

A nanostructured gas sensors made of the Fe2O3:ZnO (60 : 40 wt %) composition were fabricated. The SEM image of the gas sensitive film showed that the particle sizes in the film are ranged from 20–50 nm. The gas sensitivity characteristics of the Fe2O3:ZnO sensor to hydrogen were studied at various operating temperatures (50–250°C) and in the presence of various hydrogen concentrations (75–2000 ppm) in the ambient air. The investigated Fe2O3:ZnO sensor showed sensitivity to hydrogen starting from a temperature of 50°C, and the maximum response was observed at an operating temperature of 100°C, at which the response exceeded 5000. The optimal combination of sensor gas sensitivity parameters was observed at an operating temperature of 200°C. [ABSTRACT FROM AUTHOR]

We report a feasible and high-throughput method for high-quality W-doped VO2 nanostructured epitaxial films on r-sapphire substrate fabrication. Single-phase, smooth vanadium dioxide thin films with uniform distribution of tungsten (up to 2.3%) are formed using the solvothermal process from ethylene glycol/water V4+ and W6+ solutions. Compositional analysis by X-ray photoelectron and energy-dispersive X-ray spectroscopy (XPS and EDX, respectively); structural analysis (X-ray diffraction, Raman spectroscopy, selected area electron diffraction (SAED)); and detailed analysis of the surface morphology and substrate–film interface using scanning electron microscopy, atomic force microscopy, and high-resolution transmission electron microscopy (SEM, AFM, HRTEM, respectively) confirm the formation of nanoscale (50–60 nm) epitaxial W:VO2 (M1) on r-sapphire with epitaxial relationships (100)-VO2∥(101̅2)-Al2O3 and [010]-VO2∥[011̅0]-Al2O3. The nanostructured films demonstrate excellent terahertz (THz) transmission properties: a phase transition temperature of 31 °C, a huge THz modulation depth of over 60%, and broad bandwidth (≥2 THz) operation. Hence, they can be efficiently used as active material for tunable THz manipulation devices. [ABSTRACT FROM AUTHOR]

In this work, the temperature dependent gas sensing properties of tin-doped zinc oxide (ZnO:Sn) nanostructured films are investigated in detail. The two different contents of Sn in ZnO:Sn samples (0.1 and 0.4 at% Sn) and rapid thermal annealing (RTA) at 725 ºC were used, in order to find out the optimal conditions for the highest gas sensing properties, i.e. higher gas response, selectivity and lowest operating temperature. Generally, the Sn-doped ZnO nanostructured films showed high selectivity to volatile organic compounds (VOCs) vapors, such as ethanol, acetone, 2-propanol and n-butanol, compared to different reducing gases such as H2, NH3 and CH4. The optimal operating temperature for all films is 250 – 300 ºC and the optimal content of Sn is 0.4 at%. The as-grown films showed higher gas response compared to RTA treated ones. The gas sensing mechanism was proposed and discussed in detail.

The application of various hydrophobic/superhydrophobic coatings on the surface of metals has become the hot topic of the recent studies. The corrosion protection effectiveness and environmental issues are two important factors that should be taken into consideration when developing advanced surface coatings. Recently, the rare-earth elements (i.e., samarium) and biopolymers (i.e., polydopamine) have attracted much attention in the metals' corrosion control field. The Sm(NO 3) 3 containing solution was sprayed to the steel (St-12) sheets. Then, the Sm-modified plates were post-modified by polydopamine biopolymers that were synthesized by the self-polymerization (using tris (hydroxymethyl) aminomethane as a buffer), and oxidant-induced (using CuSO 4 as an oxidant) approaches. The structural analysis was carried out by different techniques such as contact angle (CA) test. Moreover, the electrochemical impedance spectroscopy (EIS) and polarization tests were performed to investigate the anti-corrosion performance of various samples. The CA test results revealed that by applying the nanostructured Sm-based film, the surface of the metal becomes near superhydrophobic (CA > 140°). EIS results evidenced the significant impact of the post-treatment of the Sm-treated samples by polydopamine (PDA) nanoparticles (NPs) on its corrosion protection ability enhancement. Also, the polarization test results confirmed that all treatments could retard the corrosion of steel via a mixed-type inhibition mechanism. [ABSTRACT FROM AUTHOR]

A technology was developed for manufacturing solid-state semiconductor sensor sensitive to hydrogen peroxide vapors. Gas sensitive nanostructured films made of doped metal oxide SnO2 were manufactured by the high-frequency magnetron sputtering method. The chemical composition of prepared SnO2 targets was analyzed and the thickness of the deposited doped metal oxide film was measured. The morphology of the deposited Co-doped SnO2 film was studied by scanning electron microscopy. The gas sensing characteristics to the different concentrations of hydrogen peroxide vapors at various operating temperatures were also studied. The Co-doped SnO2 sensor showed enough sensitivity to very low concentration of hydrogen peroxide vapors (875 ppb) at the operating temperature of 100 °C. The SnO2 based sensor can be successfully used in medical diagnostic apparatus for determining low concentration of hydrogen peroxide vapors in exhaled air. [ABSTRACT FROM AUTHOR]

Liquid dielectrics are widely used in high-voltage transformers owing to their excellent insulation properties. Space charge injected from electrodes can damage power systems. It is believed that space charge dynamics are related to the electrodes surface closely. In this study, surface modifications of copper and stainless-steel electrodes deposited by SiO2 and TiO2 nanostructured films with radio frequency magnetron sputtering were investigated. The films were characterized. The effects of the films on the breakdown voltage and space charge dynamics characteristics of the propylene carbonate were studied. These results indicate that when a TiO2 nanostructured film was deposited on the stainless-steel electrode, the breakdown voltage of the propylene carbonate increased by 7.3%, and when SiO2 and TiO2 films were deposited on the copper electrode, the increases were 7.4% and 10.2%, respectively. Furthermore, the amount of charge injection of the stainless-steel electrode was lower than that of the copper electrode, and the nanostructured films markedly suppressed the space charge. Both the TiO2 and SiO2 nanostructured films sputtered on the electrode surface changed the barrier height of the solid–liquid interface and reduced the depth and amount of charge injection. Compared with a sputtered SiO2 film, the TiO2 film had a better space charge suppression effect. [ABSTRACT FROM AUTHOR]

In this paper, devices fabricated with a diode-like structure (electrode/polymer/electrode) from spin-coated and nanostructured (Langmuir-Schaefer) films of polythiophene derivatives were characterized by impedance spectroscopy and studied by theoretical fitting to reach a better understanding of the physical processes in the devices. The materials used for this research were the polyalkylthiophene (P3AT) derivatives poly(3-butylthiophene) (P3BT), poly(3-hexylthiophene) (P3HT), poly(3-octylthiophene) (P3OT) and poly(3-decylthiophene) (P3DT). Electrical measurements were performed from 1 Hz to 1 MHz (100 mV ac) while increasing the dc bias in the range from 0 to 2.5 V. The fittings of the experimental results were performed using equivalent circuits. By plotting the theoretical and experimental spectra on a single graph, it was possible to obtain information related to the film morphology, interfacial effects, resistance, capacitance and conductivity of the polymer, thereby enhancing the understanding of this particular type of device. Among the P3AT films, those grown by the Langmuir-Schaefer technique showed higher electrical conductivity, with the only exception being that of P3BT.

Recent advances in nanocellulose technology have enabled production of materials for various applications with attractive properties. The aim of this work was to analyze the nanofibrillated cellulose of Eucalyptus sp. obtained by different grinding intensities. Delignified Eucalyptus sp. kraft pulp was used to obtain the nanofibrillated cellulose in the mechanical grinding process, with 2, 10 and 20 passes. Images were captured by scanning and transmission electron microscopy to observe cellulose structures. For each mechanical treatment, three films were produced, which were used to evaluate the crystallinity index. Viscosity measurement evaluated the influence of mechanical treatment on nanofibrillated cellulose. Microscopic analysis showed that the mechanical process promoted fiber defibrillation, resulting in the exposure of microfibrils in all treatments evaluated. Differences were not verified in the conformation and dimensions of the structures for the different numbers of passes, and the nanofibrils presented average diameter of approximately 30 nm. The mechanical process to obtain the nanofibrillated cellulose reduced of the crystallinity index and the viscosity of the nanofibrillated cellulose compared to cellulose before processing. The average particle size declined with rising number of grinder passes. [ABSTRACT FROM AUTHOR]

Colloidal nanoparticles (NPs) have been recently spotlighted as building blocks for various nanostructured devices. Their collective properties have been exhibited by arranging them on a substrate to form assembled NPs. In particular, electrophoretic deposition (EPD) is an emerging fabrication method for such nanostructured films. To maximize the benefits of this method, further studies are required to fully elucidate the key parameters that influence the NP deposition. Herein, two key parameters are examined, namely: (i) the aging of colloidal NPs and (ii) the charge formation by surface ligands. The aging of Cu2-xS NPs changes the charge states, thus leading to different NP deposition behaviors. The SEM images of NP films, dynamic light scattering, and zeta potential results demonstrated that the charge control and restoration of interparticle interactions for aged NPs were achieved via simple ligand engineering. The charge control of colloidal NPs was found to be more dominant than the influence of aging, which can alter the surface charges of the NPs. The present results thus reveal that the charge formation on the colloidal NPs, which depends on the surface ligands, is an important controllable parameter in EPD.

Possessing a large surface-to-volume ratio is significant to the sensitive gas detection of semiconductor nanostructures. Here, we propose a fast-response ammonia gas sensor based on porous nanostructured zinc oxide (ZnO) film, which is fabricated through physical vapor deposition and subsequent thermal annealing. In general, an extremely thin silver (Ag) layer (1, 3, 5 nm) and a 100 nm ZnO film are sequentially deposited on the SiO2/Si substrate by a magnetron sputtering method. The porous nanostructure of ZnO film is formed after thermal annealing contributed by the diffusion of Ag among ZnO crystal grains and the expansion of the ZnO film. Different thicknesses of the Ag layer help the formation of different sizes and quantities of hollows uniformly distributed in the ZnO film, which is demonstrated to hold superior gas sensing abilities than the compact ZnO film. The responses of the different porous ZnO films were also investigated in the ammonia concentration range of 10 to 300 ppm. Experimental results demonstrate that the ZnO/Ag(3 nm) sensor possesses a good electrical resistance variation of 85.74% after exposing the sample to 300 ppm ammonia gas for 310 s. Interestingly, a fast response of 61.18% in 60 s for 300 ppm ammonia gas has been achieved from the ZnO/Ag(5 nm) sensor, which costs only 6 s for the response increase to 10%. Therefore, this controllable, porous, nanostructured ZnO film maintaining a sensitive gas response, fabricated by the physical deposition approach, will be of great interest to the gas-sensing community.

Abstract A simple and cost-effective fabrication of the Zn-doped α-Fe 2 O 3 thin film as a photocathode for solar hydrogen generation was proposed in this study. Transparent Zn-doped α-Fe 2 O 3 films were prepared by a spin-coating process using nontoxic iron chloride as the iron precursor and zinc chloride as an acceptor dopant, and the thermal treatment at 550 °C in air subsequently followed up. X-ray diffraction and Raman spectroscopic characterizations suggest the α-phase to the Zn-doped hematite film, indicating that the incorporation of Zn into the Fe 2 O 3 host lattice is carried out in the absence of phase transition. X-ray photoelectron spectroscopic study otherwise demonstrates the substitution of Fe3+ for Zn2+ in the Zn-doped α-Fe 2 O 3 specimens. Mott-Schottky analysis shows that the Zn dopant functions as the hole acceptor and the carrier density is dictated by the concentration of the zinc precursor. Significantly, a notable cathodic photocurrent of −0.1 mA cm−2 is delivered by the Zn-doped α-Fe 2 O 3 photocathode with a doping level of 10% in the photoelectrochemical measurement. Last but not least, the doping effect on the photo-activity of hematite is systematically investigated that in turn works as the blueprint for materials design in the solar application. Graphical abstract Image 1 Highlights • Zn-doped Fe 2 O 3 films were synthesized by a spin-coating process followed by annealing. • Substitution of Zn ions in the Fe 2 O 3 can be confirmed by XPS and Raman spectra. • High PEC activity of Zn-doped Fe 2 O 3 film was achieved the photocurrent of −0.1 mAcm−2. [ABSTRACT FROM AUTHOR]

Abstract: The influence of the yttrium concentration on the structure of coatings prepared via the high-frequency magnetron sputtering of a metal target is investigated. The results of coating deposition in pure argon and a mixed (Ar + O2), reactive medium are discussed. It is demonstrated that a nonequilibrium body-centered-cubic solid solution based on zirconium with an extended homogeneous region (up to 16 at % Y) is formed under the condition that a target is sputtered in pure argon. During reactive-coating deposition, the formation of cubic or tetragonal zirconium dioxide is generated depending on the yttrium concentration. The tetragonal structure is created if the yttrium concentration is 8 at %. It is found that the obtained tetragonal zirconium dioxide is thermally stable both in terms of structure and in morphology upon heat treatment in air at 1100°C for 11 h. [ABSTRACT FROM AUTHOR]

Nanostructured SnO(x) films were obtained by molecular beam epitaxy (MBE). The morphology, structure, and optical properties of obtained films annealed in the temperature range of 200 °C–1000 °C were studied. The reflection high-energy electron diffraction during the film deposition by the MBE method and the x-ray phase analysis showed that the initial films are in the polycrystalline phase. A single orthorhombic SnO _2 phase was obtained for the first time after annealing the SnO(x) film in the air at a temperature of about 500 °C. The sharp change in the optical constants near the temperature of 500 °C was established using ellipsometry. The pronounced absorption edge appears in the short-wave region at temperatures above 500 °C and it disappears at lower temperatures. The film thickness changed non-monotonically during the annealing in the air. At first, it grows from 45 nm to 65 nm (active oxidation to 500 °C), and then (above 600 °C) it begins to decrease. The annealing at temperatures of 500 °C–1000 °C leads to the film compaction, since the film thickness decreases to 50 nm, but the refractive index increases by 10%–15%. Optical constants track the progress of film phase and morphological changes.

The biocidal effect of ZnO nanostructured films was studied using Escherichia coli ATCC 43897. The ZnO nanoparticles were synthesized in diethylene glycol by using zinc acetate forced hydrolysis. X-ray diffraction analysis confirmed the formation of single wurtzite-type ZnO phase with a crystallite size of 20.59 nm. Transmission electron microscopy observations revealed spherical-shaped particles in the nanoscale regime with a mean particle size of 21.96 nm. It was found that the addition of trioctylphosphine during synthesis favored much improved dispersion of ZnO nanoparticles, with smaller particle size; that is, 16.28 nm. Meanwhile, ZnO film grown onto glass substrate by spin-coating revealed single phase with the formation of aggregates (≈700) having mushroom-like morphology formed of very fine particles in the nanoscale regime. The as-deposited nanostructured films exhibited a hydrophilic character. The classical bacteriological and electrochemical impedance spectroscopy measurements enabled the biocidal effect of ZnO nanostructured films with 94% inactivation efficiency after 90 min of contact time. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to examine thermal damage and a sticking problem in the tissue after the use of a minimally invasive electrosurgical device with a nanostructured surface treatment that uses a femtosecond laser pulse (FLP) technique. To safely use an electrosurgical device in clinical surgery, it is important to decrease thermal damage to surrounding tissues. The surface characteristics and morphology of the FLP layer were evaluated using optical microscopy, scanning electron microscopy, and transmission electron microscopy; element analysis was performed using energy-dispersive X-ray spectroscopy, grazing incidence X-ray diffraction, and X-ray photoelectron spectroscopy. In the animal model, monopolar electrosurgical devices were used to create lesions in the legs of 30 adult rats. Animals were sacrificed for investigations at 0, 3, 7, 14, and 28 days postoperatively. Results indicated that the thermal damage and sticking situations were reduced significantly when a minimally invasive electrosurgical instrument with an FLP layer was used. Temperatures decreased while film thickness increased. Thermographic data revealed that surgical temperatures in an animal model were significantly lower in the FLP electrosurgical device compared with that in the untreated one. Furthermore, the FLP device created a relatively small area of thermal damage. As already mentioned, the biomedical nanostructured layer reduced thermal damage and promoted the antisticking property with the use of a minimally invasive electrosurgical device. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 865-873, 2017. [ABSTRACT FROM AUTHOR]

Understanding the interaction of water molecules with TiO 2 surface is vitally important in practical purposes. Hence, this study is focused on studying the temperature-dependent effect of water on the 5 nm-thick TiO 2 film by molecular dynamics (MD) approach. A non-reactive force field proposed by Matsui–Akaogi is applied to simulate the bulk and surface properties of TiO 2 anatase, while a developed ReaxFF reactive force field is used to predict the molecular and dissociative adsorption configurations of water molecules on the anatase (001) and (101) surfaces. The density profiles of the mentioned system provided molecular insights into the multilayer-adsorbed water on the TiO 2 surfaces at different temperatures, T . The structural properties of water, TiO 2 (anatase) and their interface were studied through the radial distribution functions of the related atomic pairs over the range 273 ≤ T ≤ 373 K. At T ≤ 313 K, strong hydrogen bonds (HBs) are found in the near-surface water molecules because of the strong liquid-surface integrations. At T ≥ 353 K, strong HBs are formed in the near-surface water molecules, while weak HBs are created on the upper layers of water because of liquid-gas interface. The reactive MD simulations showed dissociative adsorption of water molecules on the (101) surface are higher than that on the (001). This property is in good agreement with the literature data. [ABSTRACT FROM AUTHOR]

Dopamine (DA) is a crucial neurotransmitter involved in the hormonal, nervous, and vascular systems being considered as an index to diagnose neurodegenerative diseases, including Parkinson's and Alzheimer's disease. Herein, we demonstrate the quantitative sensing of DA using the peak shift in surface-enhanced Raman scattering (SERS) of 4-mercaptophenylboronic acid (4-MPBA), resulting from the concentration of DA. To enable the signal enhancement of Raman scattering, Ag nanostructure was built with one-step gas-flow sputtering. 4-MPBA was then introduced using vapor-based deposition, acting as a reporter molecule for bonding with DA. The gradual peak-shift from 1075.6 cm−1 to 1084.7 cm−1 was observed with the increasing concentration of DA from 1 pM to 100nM. The numerical simulation revealed that DA bonding induced a constrained vibrational mode corresponding to 1084.7 cm−1 instead of a C–S-coupled C-ring in-plane bending mode of 4-MPBA corresponding to 1075.6 cm−1. Proposed SERS sensors depicted reliable DA detection in human serum and good selectivity against other analytes, including glucose, creatinine, and uric acid. [Display omitted] • Dopamine is quantitatively detected with 4-MPBA deposited Ag nanostructure using SERS. • The SERS peak of 4-MPBA is gradually shifted in proportion with DA concentration. • Constrained vibration mode resulting from binding with DA induce the shift of SERS peak. • DFT calculation supports that the vibration of 4-MPBA is constrained by binding with DA. • SERS-based dopamine sensor shows good reliability and selectivity in human serum. [ABSTRACT FROM AUTHOR]

• Nanostructured indium tin oxide films were formed on preheated substrates. • Impact of substrate temperature on the antireflective properties was studied. • Nanostructured films were described by one- or two-phase models. • Control of film structural features allows one to optimize desired film properties. The influence of substrate temperature on the morphology of indium tin oxide films deposited by magnetron sputtering and electron beam evaporation is demonstrated. It is found that during magnetron sputtering, the degree of film structuring increases with a rise in the substrate temperature. Based on the X-ray phase analysis of the samples, the structured films are described in terms of two phases: the first of which is an untextured sublayer with the properties corresponding to the material obtained at room temperature; the second one is textured elongated crystals with a large cell parameter, a large crystallite size, and without microstrains. The structural features and optical characteristics of studied films are compared with the structured film obtained by electron beam evaporation. The study of transmission and reflection spectra of the obtained films show that the film deposited at a temperature of 400°C are characterized by the antireflection effect over a wide range of wavelengths. [ABSTRACT FROM AUTHOR]

Conducting polymers (CPs) are commonly explored in electrochromic devices (ECDs) because of their designable compound structure, rich color, fast switching speed, flexibility and high coloration efficiency. However, the preparation of large-size nanostructured electrochromic polymer (ECP) films is still a great challenge. Herein, we present a facile and efficient strategy to construct neat large-size nanostructured ECP films without molecular design. Polyterthiophene (PTTh), poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(2,2′-bithiophene) (PBTh) are selected as the model polymers due to their good EC behaviors. The PTTh hollow microspheres, PEDOT and PBTh nanoparticles (NPs) were prepared by in situ chemical oxidative polymerization without templates, and then were made into stable dispersions, which were processed into films by spray-coating method. The obtained films were further assembled into the ECDs. We investigated the structure, morphology and electrochemical properties of PTTh, PEDOT and PBTh films, and EC performance of corresponding ECDs. The results indicate that the uniform and loose PTTh film possesses 3D porous structure composed of many hollow microspheres, while the PEDOT and PBTh films consist of many NPs. These films exhibit good electrochemical performance. The ECD based on PEDOT film achieves an optical contrast of 29%, coloration efficiency of 217 cm2/C, and its coloration time and bleaching time are 3.48 and 0.09 s, respectively. This study suggests that in situ chemical oxidative polymerization preparation of ECP microspheres or NPs might be a facile strategy for fabricating neat large-size ECP films, and its preparation process is easily conducted, showing great potential applications in conducting polymer-based ECDs. The PTTh hollow microspheres, PEDOT and PBTh NPs were prepared by in situ chemical oxidative polymerization without templates, and then were made into stable dispersions, which were processed into films by spray-coating method. A larger device (active area: 10 × 8.5 cm2) based on PEDOT/ITO was assembled. The device can undergo reversible color changes under an applied voltage of ±3.0 V within 4 s, and displays a uniform colour switch. This work provides a simple and efficient strategy for fabricating the large-size conducting polymer-based ECDs. [Display omitted] •A facile and efficient strategy was proposed to construct neat large-size ECP films without molecular design. •The obtained ECP films composed of many hollow microspheres or nanoparticles possessed good electrochemical performance. •The larger ECD (active area: 10 × 8.5 cm2) based on PEDOT/ITO was assembled, displaying a uniform colour switch within 4 s. •The relationship of microstructure and surface morphology of ECP films to their EC properties was revealed. [ABSTRACT FROM AUTHOR]

Recently, fabrication of hydrophobic materials with application in oil spill cleanup becomes a new research focus. Herein, we report the preparation of superhydrophobic and superoleophilic steel mesh covered with nanostructured organic film for oil and organic solvents collection from water surface. The superhydrophobic mesh was fabricated by a simple deposition of carbon soot (CS) nanospheres on the steel mesh using candle combustion flam, followed by vapour phase deposition of polypyrrole (ppy). Finally the surface was modified with stearic acid (SA). The topological structure and surface wettability of the prepared mesh were characterized by SEM, FT-IR, Raman spectra and contact angle measurements. The prepared hydrophobic mesh was shaped as a miniature boat which can float on water surface and absorbs various oils from water surface very fast. Additionally, the miniature boat could be reused for many times in the oil-water separating process without decreases of its separation ability. The results illustrate that the prepared hydrophobic mesh is, low cost and can be used for facile and rapid collection of oil and other organic solvent from water surface. [ABSTRACT FROM AUTHOR]

This work demonstrates that very thin and optically transparent nanocomposite films can be conveniently applied on surface materials, displaying potent antibacterial properties without affecting the aesthetics of the underlying material. In our approach we propose new composite materials, which ensure the surface protection by inactivating the bacteria before a biofilm can be formed. The films contain very small loadings of TiO 2 , graphene, or fullerene, and can easily be applied on large surfaces using conventional brushes or air-brushes. These nanocomposite films are very promising candidates for the preservation of statues, mosaics, floors, buildings, and other objects that are exposed to challenging environmental conditions such as Architectonical Heritage or building materials (materials featuring stone, pigments, bronze, granite, marble, and glass). [ABSTRACT FROM AUTHOR]

Reliable gas sensors operating at room temperature are in demand for monitoring the environment for hazardous pollutants, such as ammonia (NH 3 ) gas that may become toxic to humans and animals above a threshold concentration. In this paper we report on the combination of three materials, namely polyaniline (PANI), graphene oxide (GO) and zinc oxide (ZnO), to produce hybrid layer-by-layer (LbL) films used for sensing NH 3 with impedance spectroscopy measurements. The deposition of tetralayered PANI/GO/PANI/ZnO LbL films was confirmed with UV–vis. absorption and Raman spectroscopies, while atomic force microscopy (AFM) served to investigate film morphology. Exposure of these LbL films to NH 3 caused film roughness to vary, in an effect that depended on the number of tetralayers. Because of synergy in the materials properties, the films with 3 tetralayers were found to be the most adequate for detecting NH 3 in the range from 25 ppm to 500 ppm with a response time of 30 s. These figures of merit are adequate for monitoring working environments regarding gas exposure, and highlight the usefulness of the control of film architecture provided by the LbL technique. [ABSTRACT FROM AUTHOR]

A new scalable-up approach to the nanostructured films with high quality non-iridescent blue color was demonstrated by cast of soft shell/hard core latex spheres synthesized via RAFT emulsion polymerization. A series of PnBA soft shell/PSt hard core latex nanospheres with different core/shell structures were synthesized via RAFT emulsion polymerization. In contrast to conventional colloidal photonic crystals, the nanostructured films possessed relatively high tensile mechanical properties resulting from the dense structures and non-iridescent structural blue color because of random phase structures. It was found that the color quality of the nanostructured films was highly dependent on the size, shape and separation degree of the dispersed phase. Unexpectedly, the irregular-shape dispersed phase around 120 nm in size and sharp phase interface were found to significantly improve the quality of blue color. When films are too thick (>0.25 mm), the color saturation would be affected, which could be partly eliminated by adding carbon black. [ABSTRACT FROM AUTHOR]

The new mathematical model of nanoparticle deposition and correlated nanostructured film growth has been developed. It is shown that the Brownian diffusion determines the final deposition rate but thermophoresis can drastically enhance it. Qualitative estimations and simulation results of nanostructured film growth are presented. For relatively small nanoparticles, some morphological parameters of the film are calculated. [ABSTRACT FROM AUTHOR]

Electrodeposition was used to fabricate nanostructured films of Ti-containing hematite for application to the photoelectrochemical (PEC) splitting of water. The morphology and microstructure of Ti-doped hematite were examined with a scanning electron microscope, X-ray diffraction, Raman spectra and X-ray photoelectron spectra. Optical absorption spectra indicated an enhanced light absorbance in Ti-doped hematite. This Ti doping increased the carrier concentration about ten-fold, confirmed with a Mott-Schottky analysis. The prepared Ti-doped hematite showed a photocurrent enhanced four-fold relative to pristine hematite. Synchrotron-based soft X-ray absorption spectra clearly revealed that a local Fe 2 TiO 5 structure in hematite formed a heterojunction, which decreased the accumulation of photogenerated holes and improved the performance. [ABSTRACT FROM AUTHOR]

Timely screening of lung cancer represents a challenging task for early diagnosis and treatment, which calls for reliable, low-cost, and noninvasive detection tools. One type of promising tools for early-stage cancer detection is breath analyzers or sensors that detect breath volatile organic compounds (VOCs) as biomarkers in exhaled breaths. However, a major challenge is the lack of effective integration of the different sensor system components toward the desired portability, sensitivity, selectivity, and durability for many of the current breath sensors. In this report, we demonstrate herein a portable and wireless breath sensor testing system integrated with sensor electronics, breath sampling, data processing, and sensor arrays derived from nanoparticle-structured chemiresistive sensing interfaces for detection of VOCs relevant to lung cancer biomarkers in human breaths. In addition to showing the sensor viability for the targeted application by theoretical simulations of chemiresistive sensor array responses to the simulated VOCs in human breaths, the sensor system was tested experimentally with different combinations of VOCs and human breath samples spiked with lung cancer-specific VOCs. The sensor array exhibits high sensitivity to lung cancer VOC biomarkers and mixtures, with a limit of detection as low as 6 ppb. The results from testing the sensor array system in detecting breath samples with simulated lung cancer VOC constituents have demonstrated an excellent recognition rate in discriminating healthy human breath samples and those with lung cancer VOCs. The recognition statistics were analyzed, showing the potential viability and optimization toward achieving the desired sensitivity, selectivity, and accuracy in the breath screening of lung cancer.

The purpose of the present study was to examine the extent of thermal injury in the brain after the use of a minimally invasive electrosurgical device with a nanostructured copper-doped diamond-like carbon (DLC-Cu) surface coating. To effectively utilize an electrosurgical device in clinical surgery, it is important to decrease the thermal injury to the adjacent tissues. The surface characteristics and morphology of DLC-Cu thin film was evaluated using a contact angle goniometer, scanning electron microscopy, and atomic force microscopy. Three-dimensional biomedical brain models were reconstructed using magnetic resonance images to simulate the electrosurgical procedure. Results indicated that the temperature was reduced significantly when a minimally invasive electrosurgical device with a DLC-Cu thin film coating (DLC-Cu-SS) was used. Temperatures decreased with the use of devices with increasing film thickness. Thermographic data revealed that surgical temperatures in an animal model were significantly lower with the DLC-Cu-SS electrosurgical device compared to an untreated device. Furthermore, the DLC-Cu-SS device created a relatively small region of injury and lateral thermal range. As described above, the biomedical nanostructured film reduced excessive thermal injury with the use of a minimally invasive electrosurgical device in the brain. [ABSTRACT FROM AUTHOR]

• A mist spin spray method was developed to fabricate nanostructured CuO thin films. • CuO thin films without impurities were fabricated at a low temperature of 90 °C. • The resulting CuO thin films showed sufficiently strong adhesion to substrates. • The film morphology could be modified by changing the precursor solutions. • Higher optical band gaps corresponded to smaller grain sizes in the films. A solution-based process, termed the mist spin spray method, was developed to fabricate nanostructured CuO thin films on seed-free glass substrates. In this method, a copper amine complex solution and a NaOH solution are separately atomized by ultrasonication to generate mists. These mists are subsequently sprayed onto a substrate heated to 90 °C and fixed on a rotating platform to grow crystalline CuO thin films at atmospheric pressure. This one-step method enables the generation of phase-pure, dense and crack-free CuO thin films below 100 °C. CuO thin films approximately 30 nm in thickness exhibited good adhesion to glass substrates, and the concentrations of NH 3 and NaOH in the initial solutions were found to affect both the film morphology and optical band gap. Specimens prepared using higher NH 3 and NaOH concentrations had larger grain sizes, while those fabricated using a low NaOH concentration showed a porous structure. A higher optical band gap was found to correlate with smaller grain sizes in the films. [ABSTRACT FROM AUTHOR]