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Three-dimensional polymer printing is becoming more popular due to its effectiveness in creating components of any geometric design. Polymer materials can be used at low temperatures but are weaker than other functional materials. Polyetheretherketone (PEEK) is a thermoplastic with outstanding mechanical properties that can tolerate high temperatures. A high-temperature fused deposition modeling machine manufactured PEEK specimens in this experiment to find the ideal printing parameters S1, S2, S3, and S4 were made using varying printing speeds and layer thicknesses. The polymer sample's exterior surface was analyzed using FESEM, while physical characterization was conducted through X-ray diffraction analysis and water contact angle measurement. The strength of each sample in the relevant variables was determined using mechanical testing, such as tensile and compression tests. It was found that specimen S3 having a layer thickness of 0.15 mm and printing speed of 20 mm/s showed a high tensile and compressive strength value of about 78 and 144 MPa respectively than the other three samples. In addition, the fractured tensile samples were analyzed with scanning electron microscopy to discover the factors that contributed to the disparity in the values of their strengths. [ABSTRACT FROM AUTHOR]

Building integrated photovoltaic (BIPV) modules with color-cover glasses have been developed to overcome design limitations in building applications. Although several current studies have presented informative outcomes through experimental analysis, understanding the long-term operating performance of color BIPV modules is still insufficient, especially when considering the transmittance features of the color-cover glass. Therefore, this study evaluates the operational performance of color BIPV modules based on comparative analysis under outdoor experimental conditions. A typical BIPV module (i.e., a non-color BIPV module) and color BIPV modules are used for this comparative analysis. The transmittance characteristics of general low-iron tempered glass (LTG) and LTG with the color coating are considered to evaluate the effect of performance degradation according to the transmittance reduction by the color coating. The thickness differences of the coating layer make different color patterns of gray, blue, and orange. In addition, the color modules are installed on the inclined (30°) and the vertical (90°) plane to assess power performance on different angle positions. Compared to the ratio of transmittance reduction (RTR) by the color coating and the percentage of efficiency reduction (RER) by the color-cover glass, the RER is less than the RTR. The RER of operational efficiency for blue and orange modules is similar to the RER in STC. Still, the RER of the gray module’s operational efficiency is about 5% greater than RER in STC. , the voltage and current characteristics for the gray module using operational data are analyzed to investigate the effect of color differences on the power efficiency. Based on the result, it was confirmed that the active efficiency reduction of the gray module is expected from the decrease in the current.

The current research focuses on sol-gel derived synthesis and RF sputter deposition of molybdenum disulphide (MoS2) over polycrystalline Si solar cell. Various coating layers were obtained under different sputter deposition at regular intervals. The influence of MoS2 sputter coating on optical, thermal chemical structural properties was examined through various characterisation techniques. 30 minutes coated solar cell reported maximum light transmittance of 95 % in the visible spectrum and minimum electrical resistivity of 2 × 10-3ohm-cm. 30 minutes coated solar cell exhibited maximum power conversion efficiency (PCE) of 19.19 % (open source) and 21.01 % (controlled source). Thermal imaging data reveal that the optimal coating layer experiences a minimum temperature of 33.9 °C and 49.9 °C. From experimental results, sputter deposited MoS2 Si solar cells experience minimum light reflectance and enhanced cell performance.

In mining industries, the prime concern is to overcome the challenges of using conical cutting bits for excavating hard and abrasive rocks. In this research, a speculative investigation was performed to measure the efficiency of rock cutting and identify the wear behavior of aluminum titanium nitride-coated conical cutting bits. A newly designed and customized shaping machine is used with a triaxial force dynamometer to cut the rock samples linearly and to calculate their associated powers. Coated conical bits have a maximum hardness range of 2,291 to 2,459 HV, and uncoated conical bits possess minimum hardness range of 1,945 to 1,948 HV. Two rock samples of fine-grained sandstone with UCS of 83.77 and 97.00 MPa are used in this study. Various cutting ranges were investigated and the best range of cutting parameters are identified between the variables, such as cutting forces and extracted volume of rock, cutting effectiveness, specific energy produced while cutting, and bit wear. The percentage decrease in wear rate of a coated conical bit compared with an uncoated conical bit is 40.36%, 52.28%, and 53.30% for Rock 1 and 42.67%, 54.76%, and 60.90% for Rock 2 under varying depths of cut. The worn surface has been significantly investigated through scanning electron microscopy and energy dispersive X-ray analysis. The output of this study helps in extending the application of a surface miner for excavating harder rocks in mines. [ABSTRACT FROM AUTHOR]

The current research focuses on sol-gel derived synthesis and RF sputter deposition of molybdenum disulphide (MoS2) over polycrystalline Si solar cell. Various coating layers were obtained under different sputter deposition at regular intervals. The influence of MoS2 sputter coating on optical, thermal chemical structural properties was examined through various characterisation techniques. 30 minutes coated solar cell reported maximum light transmittance of 95 % in the visible spectrum and minimum electrical resistivity of 2 × 10-3ohm-cm. 30 minutes coated solar cell exhibited maximum power conversion efficiency (PCE) of 19.19 % (open source) and 21.01 % (controlled source). Thermal imaging data reveal that the optimal coating layer experiences a minimum temperature of 33.9 °C and 49.9 °C. From experimental results, sputter deposited MoS2 Si solar cells experience minimum light reflectance and enhanced cell performance. [ABSTRACT FROM AUTHOR]

Polymer-metal nanocomposite thin films are versatile materials that exploit the mutualistic impact of the unique attributes of the polymer and metal nanoparticle components, enabling applications in various areas including photonics, sensing and catalysis. Sputtering followed by thermal annealing can produce metal or semiconductor nanoparticle thin films on suitable substrates. We present an optimized protocol for the fabrication of polymer-metal nanocomposite thin films, involving spin-coating of the polymer (poly(vinyl alcohol), polyaniline) film and the sputter-anneal process to form metal (silver) nanoparticles in the polymer matrix. Silver nanoparticle films and the polymer-silver nanocomposite films fabricated are characterized using UV-visible spectroscopy, electron microscopy and X-ray photoelectron spectroscopy. The polymer thin film influences significantly, the size and distribution of the nanoparticles formed within. Poly(vinyl alcohol) film is found to enable the formation of a uniform distribution of relatively small silver nanoparticles, with the annealing carried out at lower temperatures than that commonly used in the sputter-anneal procedure. Significantly, mild oxidation of the bare silver nanoparticles that occur during the annealing process is inhibited by the polymer environment. The nanocomposite formation is shown to bestow stability on the nanoparticles, against aggregation under external stimuli like the electron beam, and temporal changes under ambient atmosphere. Synopsis: Ag-polymer nanocomposite thin films are fabricated by the sputter-anneal process and the specific utility of the polymer matrix in the formation of uniform distribution and stabilization of the small nanoparticles demonstrated. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate whether boron nitride (BN) and BN--chromium (BN--Cr) coatings applied with the sputtering method would change the characteristics of hardness and discoloration of the ceramic veneer surface. Materials and Methods: In this experimental study, thirty disc-shaped cores (10 mm in diameter and 0.8 mm in thickness) were prepared. Three different ceramic systems, IPS Empress (E) (Ivoclar Vivadent, Schaan, Liechntenstein), IPS e.max Press (EP) (Ivoclar Vivadent, Schaan, Liechntenstein), and Turkom Cera (T) (Turcom-Ceramic SDN-BHD, Kuala Lumpur, Malaysia), were tested, each with n = 10. The specimens were divided into two subgroups (n = 5) according to the coating on the veneering ceramic: BN or BN--Cr. The Vickers hardness and color differences (ΔE) values were measured before and after coating. Surface analysis was performed with X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopic. The Wilcoxon signed-rank test was performed to compare hardness values. The Kruskal--Wallis test was performed to compare ΔE values among all groups. The post hoc tests was used after Kruskal--Wallis, with level of statistical significance set at P ≤ 0.05. Results: BN--Cr coating statistically significantly increased the hardness of all types of ceramics (P < 0.05). BN coating did not change the hardness statistically significantly (P > 0.05). The mean ΔE values indicated clinically noticeable (over the limit of 3.7) color change in all groups except for the EP-BN and T-BN groups. Conclusion: Although BN--Cr coating in this thickness had a negative effect on color, it increased the hardness of the ceramics and could be useful in the palatal region. [ABSTRACT FROM AUTHOR]

Scanning electron microscopy (SEM) remains distinct in its ability to allow topographical visualization of structures. Key elements to consider for successful examination of biological specimens include appropriate preparative and imaging techniques. Chemical processing induces structural artifacts during specimen preparation, and several factors need to be considered when selecting fixation protocols to reduce these effects while retaining structures of interest. Particular care for proper dehydration of specimens is essential to minimize shrinkage and is necessary for placement under the high-vacuum environment required for routine operation of standard SEMs. Choice of substrate for mounting and coating specimens can reduce artifacts known as charging, and a basic understanding of microscope settings can optimize parameters to achieve desired results. This article describes fundamental techniques and tips for routine specimen preparation for a variety of biological specimens, preservation of labile or fragile structures, immune-labeling strategies, and microscope imaging parameters for optimal examination by SEM. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Chemical preparative techniques for preservation of biological specimens for examination by SEM Alternate Protocol 1: Practical considerations for the preparation of soft tissues Alternate Protocol 2: Removal of debris from the exoskeleton of invertebrates Alternate Protocol 3: Fixation of colonies grown on agar plates Alternate Protocol 4: Stabilization of polysaccharide structures with alcian blue and lysine Alternate Protocol 5: Preparation of non-adherent particulates in solution for SEM Support Protocol 1: Application of thin layer of adhesive on substrate to improve adherence Support Protocol 2: Poly-L-lysine coating specimen substrates for improved adherence Support Protocol 3: Microwave processing of biological specimens for examination by SEM Basic Protocol 2: Critical point drying of specimens Alternate Protocol 6: Chemical alternative to critical point drying Basic Protocol 3: Sputter coating Alternate Protocol 7: Improved bulk conductivity through "OTOTO" Basic Protocol 4: Immune-labeling strategies Alternate Protocol 8: Immune-labeling internal antigens with small gold probes Alternate protocol 9: Quantum dot or fluoronanogold preparations for correlative techniques Basic Protocol 5: Exposure of internal structures by mechanical fracturing Basic Protocol 6: Exposure of internal structures of tissues by fracturing with liquid nitrogen Basic Protocol 7: Anaglyph production from stereo pairs to produce 3D images., (Published 2024. This article is a U.S. Government work and is in the public domain in the USA. Current Protocols published by Wiley Periodicals LLC.)

Cellulose nanocrystals (CNCs) are prepared for transmission electron microscopy (TEM) using positive or negative stains in an effort to increase the contrast between the specimen and background. When imaging CNCs, conventional stains have been shown to induce particle aggregation and produce artifacts. In this study, we report on methods used to image CNCs. To increase contrast and decrease artifacts and aggregation, sputter coating was used to coat the samples. CNCs were loaded onto copper grids and sputter coated with one of four different metals: iridium, carbon, gold, and titanium. The final layer was deposited at 5 nm to ensure surface homogeneity. The thin layer of conductive metal atoms deposited onto the specimen surface significantly increased contrast and improved image quality. The results presented here demonstrate the advantages of using sputter coating for imaging of highly crystalline cellulose materials with TEM. [ABSTRACT FROM AUTHOR]

Erbium oxide (erbia/Er2O3) is one of the leading candidate coating types to address the issues of tritium permeation reduction and Magnetohydrodynamic (MHD) drag reduction in fusion reactor with liquid Lead–Lithium (Pb–Li) or molten salt Flibe (2LiF+BeF2) as the coolant and breeder materials. The electrical resistivity, hydrogen/deuterium permeation reduction property, liquid metal corrosion, radiation effects and deposition techniques are major areas of research on erbia coating. Though it is having a single stable phase of cubic structure up to 2300°C, it is known to develop metastable monoclinic phase especially in sputter coating methods. We grow erbia by reactive magnetron sputter coating method and study the phase formation, electrical, microstructural and optical dielectric properties. The effects of erbium metal pre-layer deposition, post annealing in oxygen rich vacuum and oxygen to argon gas feed ratio are studied keeping other parameters constant. The film grows in mixed phase of cubic and monoclinic structures when erbium metal pre-layer is deposited on the P91 steel substrate and in pure monoclinic phase in absence of the pre-layer. Post annealing seems to partially convert monoclinic into cubic phase in the mixed phase coating. Better crystallization and slightly more surface roughness is observed in the sample processed with higher oxygen to argon ratio. DC resistivity is found in 1015Ω*cm range and it is marginally more in the sample processed with more oxygen. The spectroscopic ellipsometry on these films to obtain optical dielectric properties gives encouraging results in terms of close match of the thickness and roughness values with those obtained from SEM and AFM respectively. Systematic study of optical dielectric property suggests a trend consistent with DC resistivity.

Background: The aim of this study was to investigate whether boron nitride (BN) and BN–chromium (BN–Cr) coatings applied with the sputtering method would change the characteristics of hardness and discoloration of the ceramic veneer surface. Materials and Methods: In this experimental study, thirty disc-shaped cores (10 mm in diameter and 0.8 mm in thickness) were prepared. Three different ceramic systems, IPS Empress (E) (Ivoclar Vivadent, Schaan, Liechntenstein), IPS e.max Press (EP) (Ivoclar Vivadent, Schaan, Liechntenstein), and Turkom Cera (T) (Turcom-Ceramic SDN-BHD, Kuala Lumpur, Malaysia), were tested, each with n = 10. The specimens were divided into two subgroups (n = 5) according to the coating on the veneering ceramic: BN or BN–Cr. The Vickers hardness and color differences (ΔE) values were measured before and after coating. Surface analysis was performed with X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopic. The Wilcoxon signed-rank test was performed to compare hardness values. The Kruskal–Wallis test was performed to compare ΔE values among all groups. The post hoc tests was used after Kruskal–Wallis, with level of statistical significance set at P ≤ 0.05. Results: BN–Cr coating statistically significantly increased the hardness of all types of ceramics (P < 0.05). BN coating did not change the hardness statistically significantly (P > 0.05). The mean ΔE values indicated clinically noticeable (over the limit of 3.7) color change in all groups except for the EP-BN and T-BN groups. Conclusion: Although BN–Cr coating in this thickness had a negative effect on color, it increased the hardness of the ceramics and could be useful in the palatal region.

Recent critical issues regarding next-generation energy storage systems concern the cost-effective production of lightweight, safe and flexible supercapacitors yielding high performances, such as high energy and power densities as well as a long cycle life. Thus, current research efforts are concentrated on the development of high-performance advance electrode materials with high capacitance and excellent stability and solid electrolytes that confer flexibility and safety features. In this work, emphasis is placed on the binder-free, needle-like nanostructured Mn/MnOx layers grown onto graphite-foil deposited by reactive sputtering technique and to the polymer gel embedded ionic electrolytes, which are to be employed as new flexible pseudocapacitive supercapacitor components. Microstructural, morphological and compositional analysis of the layers has been investigated by X-ray diffractometer (XRD), Field Emission Scanning Electron Microscope (FE–SEM) and X-ray photoelectron spectroscopy (XPS). A flexible lightweight symmetric pouch-cell solid-state supercapacitor device is fabricated by sandwiching a PPC-embedded ionic liquid ethyl-methylimidazolium bis (trifluoromethylsulfonyl) imide (EMIM)(TFSI) polymer gel electrolyte (PGE) between two Mn/MnOx@Graphite-foil electrodes and tested to exhibit promising supercapacitive behaviour with a wide stable electrochemical potential window (up to 2.2 V) and long-cycle stability. This pouch-cell supercapacitor device offers a maximum areal capacitance of 11.71 mF/cm2@ 0.03 mA/cm2 with maximum areal energy density (Ea) of 7.87 mWh/cm2 and areal power density (Pa) of 1099.64 mW/cm2, as well as low resistance, flexibility and good cycling stability. This supercapacitor device is also environmentally safe and could be operated under a relatively wide potential window without significant degradation of capacitance performance compared to other reported values. Overall, these rationally designed flexible symmetric all-solid-state supercapacitors signify a new promising and emerging candidate for component integrated storage of renewable energy harvested current.

Nanoparticles are efficient matrices in laser desorption/ionization (LDI) mass spectrometry (MS), especially for the profiling or imaging of small molecules. Recently, solvent-free physical vapor desorption (PVD), or sputter coating, was adopted as a homogenous method to rapidly apply metal nanoparticles (NPs) in situ to samples prior to LDI MS or MS imaging analysis. However, there has been no systematic study comparing different metal targets for the analysis of a variety of small molecule metabolites. Here, we present a screening and optimization of various sputter-coated metals, including Ag, Au, Cu, Pt, Ni, and Ti, for LDI analysis of small molecules in both positive and negative ion modes. Optimized sputter coating is then applied to high-spatial resolution LDI mass spectrometry imaging (MSI) of maize root and seed cross-sections. Noble metals, Ag, Au, and Pt, are found to be much more efficient than transition metals and organic matrices for most small metabolites. Sputter-coated metals are efficient for neutral lipids, such as triacylglycerols and diacylglycerols, but are very inefficient for most phospholipids.ᅟ [ABSTRACT FROM AUTHOR]

Zirconium carbide (ZrC) films are deposited onto polyester fabric through magnetron sputtering. The deposited films are then examined by using field scanning electron microscopy and energy dispersive X-ray spectroscopy. The photothermal conversion property, film thickness, infrared reflectance and transmittance, and thermal conductivity are also evaluated. The results show that the highest far-infrared emissivity of polyester fabric deposited with ZrC is 0.9379. The ZrC deposited samples showed a small increase in thermal conductivity with a difference of 0.0611W/m·K, and a higher photothermal conversion efficiency with a temperature increase of 27.5 °C in 100 s, when the thickness of the ZrC film is 1920 nm. These therefore indicate that coating fabrics with ZrC through magnetron sputtering is an environmentally friendly means to produce textiles with photo-thermal conversion and heat insulation properties. [ABSTRACT FROM AUTHOR]

With capacitive fingerprint readers being increasingly used for access control as well as for smartphone unlock and payments, there is a growing interest among metrology agencies (e.g., the National Institute of Standards and Technology) to develop standard artifacts (targets) and procedures for repeatable evaluation of capacitive readers. We present our design and fabrication procedures to create conductive 3D targets (gold fingers) for capacitive readers. Wearable 3D targets with known feature markings (e.g., fingerprint ridge flow and ridge spacing) are first fabricated using a high-resolution 3D printer. A sputter coating process is subsequently used to deposit a thin layer (~300 nm) of conductive materials (titanium and gold) on 3D printed targets. The wearable gold finger targets are used to evaluate a PIV-certified single-finger capacitive reader as well as small-area capacitive readers embedded in smartphones and access control terminals. In additional, we show that a simple procedure to create 3D printed spoofs with conductive carbon coating is able to successfully spoof a PIV-certified single-finger capacitive reader as well as a capacitive reader embedded in an access control terminal. [ABSTRACT FROM PUBLISHER]

Different unmodified and modified semiconductor photocatalysts were used for the complete decolorization of an unbuffered crystal violet solution. The decolorization efficiency of commercially available ZnO and TiO2 (anatase nanopowder) was compared with those of newly prepared goldmodified ZnOs (Au/ZnOs). Two Au/ZnOs were prepared from pure ZnO powder through deposition of gold by direct current (DC) sputtering. The morphological characterization of the Au/ZnOs was done with the aid of scanning electron microscopy. ZnO-based catalysts show significantly higher decolorization power in comparison with TiO2. Au/ZnOs show slightly higher activity than unmodified ZnO. [ABSTRACT FROM AUTHOR]

In this study, unsupported platinum and platinum-cobalt ultra-thin catalyst layers with varying metal loadings were prepared by a sequential magnetron sputtering technique. The deposited catalyst layers were characterized using X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), X-ray diffraction, cyclic voltammetry, and rotating disk electrode methods. Ultra-low Pt loadings, in the range of 6-22 µg cm, were used to examine the kinetic properties of the deposited catalyst layers. The results revealed that the highest electrochemically active surface area, 89.7 m g, was obtained for Pt:Co (1:3) nanocatalyst with an optimum Pt loading of 10 µg cm. The XPS and UPS results indicated that the catalyst layers prepared at elevated temperatures contained a high degree of Pt-Co interaction. It was seen that the incorporation of Co atoms into the Pt lattice improved the oxygen reduction reaction (ORR) activity of the catalysts at certain Pt:Co concentrations and sputtering temperatures. Among all catalyst layers, the highest mass and specific current density values (793.08 A $${\text{g}}_{\text{Pt}}^{ - 1}$$ and 1163.18 µA cm, respectively) were obtained from the electrode with 10 µg cm Pt loading prepared at 300 °C. Although the introduction of Co atoms in the catalyst layer did not result in a systematic enhancement in the ORR performance, the Pt:Co (1:1) composition deposited at 300 °C had the highest ORR performance with a mass activity of 571.17 A $${\text{g}}_{\text{Pt}}^{ - 1}$$ and a specific activity of 835.59 µA cm among the all Co-containing catalysts. Our results indicated that heat treatment, surface structure, and composition have profound effects on the performance of the catalyst layers. Graphical Abstract : [ABSTRACT FROM AUTHOR]

Aluminum doped zinc oxide (AZO) film was deposited onto a polyester fabric by magnetron sputtering. The coated fabric samples were then systematically investigated by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy and Fourier transform infrared spectroscopy. The thickness of the AZO film on fabric samples was also evaluated, as well as the water repellency, ultraviolet protection factor (UPF) and infrared emissivity. The results showed that the AZO coated fabric presented higher water repellency with a contact angle (CA) of 146° and substantial reduction of ultraviolet transmittance with a UPF value of 362. The infrared emissivity of the AZO coated polyester fabric was reduced to 0.916 in comparison to the untreated fabric of 0.979, when the thickness of the AZO coating was 450 nm. [ABSTRACT FROM AUTHOR]

PA6 nanofibers were electrospun successfully and sputter coated with gold and palladium to create functional nanofibrous membranes that possess electromagnetic shielding ability. Properties of the electrospinning solutions were analyzed in terms of viscosity, conductivity and pH values. Coating thicknesses of the nanofibrous membranes were determined as 50 nm and 100 nm. Morphology of the nanofibrous membranes were observed by SEM analysis. Elemental composition of the specimens was explored by using Energy Dispersive Spectroscopy. Results revealed that defect free and uniform nanofibers were obtained, and the diameters of the fibers were changed after coating. Tensile strength and elongation measurements confirmed that the mechanical characteristics of the nanofibrous membranes were merely altered after coating. Electromagnetic Shielding Effectiveness (EMSE) of the nanofibers was determined according to the ASTM D4935-10 protocol by using coaxial transmission line measurement technique in the frequency range of 15–3000 MHz. It was observed that 100 nm coated membrane performed better EMSE than uncoated and 50 nm coated nanofibrous membranes. [ABSTRACT FROM AUTHOR]

We demonstrate a pathway for fully roll-to-roll (R2R) prepared organic solar cells in a normal geometry with a R2R sputtered aluminium top electrode. Initial attempts utilizing a stack geometry without an electron transport layer (ETL) failed to obtain working devices. By applying aluminium zinc oxide (AZO) as an ETL, and optimizing the AZO thickness, working printed OPV devices with an efficiency of 0.58% were obtained. Further optimization of the donor:acceptor ratio in the active layer increased the efficiency to 0.90%. This work demonstrates that normal geometry organic solar cells using a metal top contact can be produced using large scale production techniques. [ABSTRACT FROM AUTHOR]

A new method is reported to grow polycrystalline germanium (Ge) on silicon (Si) at low temperatures by direct current magnetron sputtering. The method is based on first sputtering a nanometre scale thickness Si layer on a Si substrate, followed by sputtering a Ge layer of the desired thickness. Using this approach, polycrystalline Ge has been deposited on Si substrate at 300°C, the lowest reported process temperature for polycrystalline Ge on Si by sputter coating. Characterisation by X‐ray diffraction and Raman spectroscopy showed polycrystalline Ge in the presence of a Si interfacial layer. In the absence of the interfacial Si layer, amorphous Ge was obtained under the same process conditions. These observations indicate that depositing a Si interfacial layer helps in improving the Ge film quality in low‐temperature deposition conditions. The approach developed here makes it possible to achieve post‐CMOS integration in applications that have low thermal budget, such as flexible electronics based on Si/Ge devices. The increased process flexibility offered by this method is also expected to enable new applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Blisters are observed in Au sputter-coating on Ni-based single crystal superalloy. • Their diameters increase, but diameter-to-height ratios don't, with film thickness. • They prefer to form on the γ-matrix rather than the γ′-precipitate or Si substrate. • DFT calculations indicate a higher tendency of moisture adsorption on γ than on γ′. • Mechanical modelling shows blistering is driven by pocket of energy concentration. Au thin films, up to h ≈ 90 nm thick, have been deposited by direct current sputtering at room temperature to address the effect of coating thickness on film blistering that occurred on Ni-based single crystal (NBSC) superalloy rather than on Si. Transmission electron microscopy provides evidence that the blisters nucleated at the Au/NBSC interface. Statistically, the diameters of the blisters increases while their density decreases with the increase in h ; however, the height-to-diameter ratios of the blisters measured from the film surface are rather constant and independent of h. When h is increased from ≤63 nm to ∼90 nm, the size distribution of the blisters turns from a single mode to a bimodal along with an emergence of larger circular blisters and edge-like ones. Mechanical modelling and density-function calculations provide evidence that the formation of blisters is driven by pockets of energy concentration while the nucleation site is influenced by surface absorbents of the substrate. [ABSTRACT FROM AUTHOR]

The potential for organic electronic technologies to produce low-cost energy at large scales is often cited as the most attractive feature of these materials. Such aspirations depend on the ability of materials to be printed from solution at high speeds across large areas using roll-to-roll (R2R) processing. However, progressing the technology from the laboratory environment into the industrial manufacturing arena is highly challenging. Closing the gap between exciting laboratory scale insights and the industrial scale potential requires a new focus on upscaling existing technology. Some recent progress in this area is discussed, concentrating on the need to pursue research across several different scales simultaneously in order to most effectively optimize large-scale fabrication efforts. These discussions are placed in the context of a design philosophy that combines printing, coating, and vacuum-based procedures. The challenges associated with selecting, and subsequently synthesizing, the optimal materials for device construction at large scales are considered. Case histories that highlight the unique challenges encountered during printing, coating, and sputtering at the R2R scale are presented. Developing testing and characterization procedures that can interrogate organic photovoltaic device (OPV) structures in real time is also discussed, and the opportunity for new tools to probe device photophysics is highlighted. The collection of innovative approaches to R2R fabrication challenges discussed here highlights the exciting progress toward efficient OPV modules becoming a commercial reality. [ABSTRACT FROM PUBLISHER]

Profiling and imaging of cholesterol and its precursors by mass spectrometry (MS) are important in a number of cholesterol biosynthesis disorders, such as in Smith-Lemli-Opitz syndrome (SLOS), where 7-dehydrocholesterol (7-DHC) is accumulated in affected individuals. SLOS is caused by defects in the enzyme that reduces 7-DHC to cholesterol. However, analysis of sterols is challenging because these hydrophobic olefins are difficult to ionize for MS detection. We report here sputtered silver matrix-assisted laser desorption/ionization (MALDI)-ion mobility-MS (IM-MS) analysis of cholesterol and 7-DHC. In comparison with liquid-based AgNO and colloidal Ag nanoparticle (AgNP), sputtered silver NP (10-25 nm) provided the lowest limits-of-detection based on the silver coordinated [cholesterol + Ag] and [7-DHC + Ag] signals while minimizing dehydrogenation products ([M + Ag-2H]). When analyzing human fibroblasts that were directly grown on poly-L-lysine-coated ITO glass plates with this technique, in situ, the 7-DHC/cholesterol ratios for both control and SLOS human fibroblasts are readily obtained. The m/z of 491 (specific for [7-DHC + Ag]) and 495 (specific for [cholesterol + Ag]) were subsequently imaged using MALDI-IM-MS. MS images were co-registered with optical images of the cells for metabolic ratio determination. From these comparisons, ratios of 7-DHC/cholesterol for SLOS human fibroblasts are distinctly higher than in control human fibroblasts. Thus, this strategy demonstrates the utility for diagnosing/assaying the severity of cholesterol biosynthesis disorders in vitro. Graphical Abstract [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

We report the demonstration of sputter-coated aluminum contacts directly onto P3HT:PCBM organic photovoltaic devices using a R2R process without detrimentally influencing the performance of the devices. The final sputtered devices do not require any protective buffer layers to produce efficient performance. Depth profiling analysis of sputtered films using X-ray photoelectron spectroscopy (XPS) indicated the presence of a 5-6 nm insulating oxide layer generated at the cathode interface for all sputtering target power densities greater than 1.4 W cm−2. The aluminum penetration into the P3HT:PCBM film was found to be consistent with the depth of this oxide layer, suggesting that aluminum penetration into the organic film is not the primary reason for performance limitations in sputtered devices. Introduction of thermally evaporated aluminum buffer layers prior to deposition of sputtered aluminum cathodes demonstrated that the performance of devices after annealing matched those of reference devices prepared with no sputtering for a buffer layer thickness of only 20 nm. Further analysis of the device J- -V curves revealed an S-shaped kink prior to annealing, indicating that the major reason for the poor performance in sputtered devices was the introduction of a charge extraction barrier at the cathode, which was subsequently removed upon annealing. Rigorous removal of oxygen from the sputtering chamber prior to aluminum deposition onto the P3HT:PCBM active layer was subsequently observed to produce a device with an efficiency close to that of the thermally evaporated reference device without the requirement for evaporated buffer layers. The results presented here highlight a pathway towards an alternative R2R cathode fabrication technique that allows the highly efficient aluminum cathodes employed in small-scale devices to be transferred onto large-scale, flexible, and low-cost R2R printed organic electronic devices. [ABSTRACT FROM AUTHOR]

This study evaluated the quantity and quality of newly formed vertical bone induced by sputtered hydroxyapatite-coated titanium implants compared with sandblasted acid-etched implants after dura mater elevation. Hydroxyapatite-coated and non-coated implants (n = 20/group) were used and divided equally into two groups. All implants were randomly placed into rabbit calvarial bone (four implants for each animal) emerging from the inferior cortical layer, displacing the dura mater 3 mm below the original bone. Animals were sacrificed at 4 (n = 5) and 8 (n = 5) weeks post-surgery. Vertical bone height and area were analyzed histologically and radiographically below the original bone. Vertical bone formation was observed in both groups. At 4 and 8 weeks, vertical bone height reached a significantly higher level in the hydroxyapatite compared with the non-coated group (p < 0.05). Vertical bone area was significantly larger in the hydroxyapatite compared with the non-coated group at 4 and 8 weeks (p < 0.05). This study indicates that vertical bone formation can be induced by dura mater elevation and sputtered hydroxyapatite coating can enhance vertical bone formation. [ABSTRACT FROM AUTHOR]

This work describes that bacterial cellulose was successively modified by copper/zinc nanoparticles with the help of direct current and radio frequency magnetron sputter-coating method for electromagnetic interference shielding to enhance its hydrophobic, mechanical, and conductive properties. The surface morphology and properties of bacterial cellulose/copper/zinc nanocomposite were analyzed by various testing methods (X-ray photoelectron spectroscopy, X-ray diffraction) and instruments to analyze smooth deposition of metallic nanoparticles. The conductive and shielding effects were examined by a four-point probe and vector analyzer. The mechanical properties were investigated by a uniaxial testing machine. The combined structure of bacterial cellulose, copper, and zinc nanoparticles (Zn–Np) improves the surface hydrophobicity, mechanical strength, as well as electromagnetic interference shielding effectiveness, while zinc nanoparticles act as a protective layer over the surface of bacterial cellulose/copper nanocomposite. So, the findings revealed that the bacterial cellulose/copper/zinc nanocomposite has excellent hydrophobic (θ ; 143.7°), good mechanical (T.F; 39.67 MPa, elongation; 13.1%, Y.M; 5.90 MPa), conductive (50 W; 0.0323 S/m), and electromagnetic interference shielding (28.54 dB) properties. [ABSTRACT FROM AUTHOR]

Abstract: Silver-coated poly(lactide) (PLA) films were prepared by using a vacuum sputter coating method and their film properties were investigated. Smooth-surfaced flexible and free-standing silver-coated PLA films were obtained after coating for 2 min and 10 min. The silver-coated PLA film coated for 2 min was translucent, while that coated for 10 min was opaque with shiny metallic luster. The water vapor barrier and oxygen gas barrier properties decreased significantly (p < 0.05) as time of coating increased, while surface hydrophobicity increased significantly without sacrificing the tensile properties after silver-coating. Film properties, such as optical, film thickness, basis weight, thermal stability, tensile, and gas barrier properties were influenced by the coating time. Noise problem caused by brittleness of the PLA film has been partly mitigated to provide value-added application in the food packaging industry. [Copyright &y& Elsevier]

Ceramic fibers were functionalized by the sputter coating of copper in this study. The surface and interface structures of the functionalized ceramic fibers were investigated by atomic force microscopy (AFM) and environmental scanning electron microscopy (ESEM). The observations by AFM revealed the formation of nanoclusters on the fiber surface. The coated layer of the sputtered copper was also confirmed by the ESEM examination, equipped with an energy-dispersive X-ray analysis. It was also found that the electrical resistance of the ceramic fibers decreased with increased coating thickness. The interfacial bonding between fibrous substrate and sputter-coated copper was investigated and discussed by peel-off tests in this study. The mechanism of the interfacial adhesion between copper and fiber substrate was also discussed. [ABSTRACT FROM AUTHOR]

Abstract: A dynamic acetonitrile | aqueous electrolyte phase boundary in contact with platinised Teflon working electrodes is investigated. High concentrations of salt in the aqueous phase (2M NaCl and 0.1M NaClO4) ensure immiscibility and the polar nature of acetonitrile aids the formation of a well-behaved triple phase boundary reaction zone. The one-electron oxidation of tert-butylferrocene in the organic phase without intentionally added electrolyte is studied. The limiting current for the flowing triple phase boundary process is shown to be essentially volume flow rate independent. The process is accompanied by the transfer of perchlorate from the aqueous into the organic phase and the flux of anions is shown to be approximately constant along the dynamic acetonitrile | aqueous electrolyte | platinum line interface. A high rate of conversion (close to 100%) is achieved at slow volume flow rates and at longer platinum electrodes. [Copyright &y& Elsevier]

Gold-doped titanium dioxide (TiO2:Au) nanofibers were prepared by a combination of an electrospinning method and sputtering technology and characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that the morphologies of Au-deposited TiO2 nanofibers can be well controlled by the sputtering time. The photocatalytic decomposition of acetaldehyde on TiO2:Au nanofibers was investigated at room temperature. The photocatalytic effect of the TiO2 nanofiber was improved by using the Au-doped titania nanofibers catalyst and increased as the Au depositing time was increased from 40 s to 3 min. The photocatalytic removal rate of acetaldehyde remained above 94% on the TiO2:Au nanofibers (2 min) catalyst under ultraviolet (UV) irradiation for 70 min, 1.7 times that of pure TiO2 fibers. [ABSTRACT FROM AUTHOR]

Abstract: The surface properties of polymer nanofibers are of importance in various applications. In this work, electrospun polyamide nanofibers were used as substrates for creating functional nanostructures on the nanofiber surfaces. The surface functionalization of polymer nanofibers was made by reactive sputtering of zinc (Zn). The surface structures of the sputter-coated nanofibers were examined by atomic force microscopy (AFM) and environmental scanning electron microscopy (ESEM). AFM results revealed the formation of functional coatings on the nanofiber surface. A full energy dispersive X-ray analysis (EDX) mounted on the ESEM confirmed the chemical compositions of the nanofiber surfaces. The electrical conductivity and light transmittance of the functional nanofibers were also investigated. The results indicated that the nanofibers deposited with zinc films significantly improved the surface conductivity and the reactive sputter coating of zinc oxide obviously enhanced the ultra-violet absorption. [Copyright &y& Elsevier]

Abstract: In the present work, Fe-montmorillonite was synthesized by hydrothermal method, and then was modified by cetyltrimethyl ammonium bromide (CTAB). The polyamide6 (PA6) nanofibers and PA6/organic-modified Fe-montmorillonite (Fe-OMT) nanocomposite fibers were firstly prepared by a facile compounding process with electrospinning, and then coated by silicon nanoparticles (Si) using magnetron sputter technique. The High-resolution transmission electron microscopy (HRTEM) image indicated that the silicate clay layers were well dispersed within the nanocomposite fibers and aligned almost along the axis of the nanofibers. The influences of the Si sputter coating on structures, surface morphology, thermal and flammability properties of PA6 nanocomposite fibers were characterized by Scanning electron microscope (SEM), Energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Atomic force microscope (AFM), Thermogravimetric analyses (TGA) and Micro Combustion Calorimeter (MCC), respectively. The SEM images showed that the diameters of nanocomposite fibers were decreased with the loadings of the Fe-OMT, and the Si thin film with nanoparticles were well coated on the surface of homogeneous and cylindrical nanofibers. The EDX analyses confirmed the presences of the Fe-OMT and Si nanoparticles on the nanofibers. The XPS spectra reflected the chemical features of the deposited nanostructures. The AFM observations revealed a remarkable difference in the surface morphology of nanocomposite fibers after sputter coating. The TGA analyses indicated the barrier effects of silicate clay layers, catalysis effect of Fe3+ and synergistic effects between the Fe-OMT and Si improved thermal stability properties of the coated nanocomposite fibers. It was found from the MCC tests that the peak of heat release rate (PHRR) of the coated nanocomposite fibers decreased significantly, contributing to the improved flame retardant properties. [Copyright &y& Elsevier]

Abstract: In the present work, the pure polyamide6 (PA6) nanofiber and PA6/organically modified montmorillonite (O-MMT) composite nanofiber were firstly prepared by a facile compounding process with electrospinning, and then coated by nanosize Fe2O3 using magnetron sputter technique. The effects of Fe2O3 sputter coating on structures, surface morphology and thermal stability were characterized by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), atomic force microscope (AFM) and thermogravimetric analyses (TGA), respectively. The SEM images showed that the diameters of composite nanofiber were decreased with the loadings of O-MMT and the nanosize Fe2O3 is well coated on the surface of the homogeneous and cylindrical nanofibers. The XPS spectra reflected the chemical features of the deposited nanostructures. The EDX confirmed the presence of the O-MMT and Fe2O3 in the fibers. The AFM observation revealed that there was a remarkable difference in the surface morphology of composite nanofiber before and after sputter coating. The TGA analysis indicated the barrier effects of silicate clay layers and catalysis effects of Fe2O3 improved thermal stability properties of the composite nanofiber. [Copyright &y& Elsevier]

Fibrous textiles have been increasingly used in a variety of industries. In these applications, the surface properties of textile materials play a very important role. The surface properties of textile materials can be modified by various techniques. Copper (Cu) nanocomposite textiles are prepared by magnetron sputter coating. The nanocomposite textiles with different thickness of coatings are investigated by atomic force microscope (AFM), energy-dispersive X-ray analysis, and opto-electrical tests. The AFM observations reveal the growth of the Cu nanostructures formed on the fiber surface as the sputtering time increases. The surface conductivity of the textiles coated with Cu nanostructures shows a significant increase compared to the uncoated ones. The increased coating thickness leads to better electrical conductivity. The coated textiles also show considerable improvement in UV and visible light shielding, examined by UV/Vis spectrometer. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of indium tin oxide (ITO) were deposited onto plastic web (PET) by reactive DC magnetron sputtering from a ceramic target of In2O3/SnO2 (90:10). The layer thickness and partial pressure of H2O were varied. After coating, the PET was heated up to 175 °C by various annealing steps. The films were then examined by XRD, SEM, UV/VIS/NIR spectroscopy, and optical light microscopy. The sheet resistivity was also measured. With a low H2O partial pressure of 3.2·10−5 Pa, polycrystalline ITO layers were deposited. At a higher H2O partial pressure of 3.06·10−3 Pa, the ITO layers were grown with an amorphous structure. Shrinkage of the PET substrate during the annealing process initiated severe cracking in the ITO layer. The magnitude of crack formation was found to depend on three parameters; annealing temperature, layer structure, and layer thickness. Moreover, crack formation decreased the ITO film quality by increasing the sheet resistance. [Copyright &y& Elsevier]

A sputter-coated gold film, of variable thickness, was used to protect the near surface region structure of an AlAs–InAs superlattice from damage during transmission electron microscope (TEM) specimen preparation using a focused ion beam (FIB) miller. This coating was applied before the deposition of any platinum protective film in the FIB. The extent of any damage in this specimen was investigated by TEM. Where the gold film was either locally absent or of low thickness (<15 nm), ion beam damage of this near surface region was evident. It was concluded that the deposition of platinum in the FIB may lead to surface modification of TEM specimens and that the application of a gold layer at least 60 nm in thickness should be made prior to any FIB processing. [Copyright &y& Elsevier]