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The demand for the development of high-capacity, safe, and long-life secondary batteries and the interest in all-solid-state batteries are increasing. The cycle performance of solid-state batteries is limited by interfacial phenomena at the electrolyte–anode interface hindering the ion diffusions. A multifunctional aluminum oxide (specifically, Al2O3) coating was created for application on silicon-based anodes in all-solid-state lithium-ion batteries. In an all-solid-state lithium-ion battery, the electrochemical properties of Al2O3 coating were enhanced. The coating was applied to provide stable artificial solid electrolyte interphase (SEI) layers on the silicon-based anodes. Al2O3 layers not only promote the diffusion of Li+ through the Li–Al–O, but their intrinsically low electronic conductivity also limits the transmission of electrons at the contact between the anode and the electrolyte. A Si alloy–polyacrylonitrile anode was prepared using Al2O3 coating as an artificial SEI layer by radio-frequency (RF) plasma. Radio-frequency sputtering was used to create a simple and economical Al2O3 coating. The cycle properties of silicon-based anodes were enhanced by the addition of the thin amorphous aluminum oxide layer (i.e., Al2O3 coating). After 100 charge–discharge cycles, the half-cell with the Al2O3 layer delivered a discharge capacity of 502.08 mAh g−1 and a capacity retention ratio of 58.86%. After 100 cycles, the sample without the Al2O3 layer had a discharge capacity of 278.48 mAh g−1 and capacity retention of 34.34%. Cells with an Al2O3 -coated anode retained high capacity after 100 cycles. Thus, the Al2O3 -coated Si-based anodes were cycled successfully in all-solid-state half-cells to produce functional high-performance lithium-ion batteries. In this study, we employed the vacuum deposition method, radio-frequency sputtering, to deposit very thin layer of aluminum oxide on the surface of fully fabricated anodes for improved cycling properties of all solid-state battery. This layer of aluminum oxide was confirmed using advanced elemental analysis techniques. The aluminum oxide layer with 1-min coating had much-improved cycling characteristics compared with those of the sample with no coatings. Previous studies have used theoretical calculations to report that an aluminum oxide coating layer improves the stability characteristics for sulfide-based solid electrolytes. In this paper, the actual stability improvement of the sulfide-based solid electrolyte was demonstrated in terms of much improved cycling characteristics throughout the cycling test. The appropriate amount of aluminum oxide coating decreases the decomposition of solid electrolyte and also decreases the consumption of Li ions during lithiation and delithiation. This surface modification technique can be utilized to improve the cycling stability of solid-state batteries, which is one of the critical factors for the early adoption of solid-state batteries for electric vehicle applications. [ABSTRACT FROM AUTHOR]

In the field of waterproofing concrete structures, the use of self-adhesive waterproofing sheets has become a popular technique for ensuring long-term waterproofing performance. One important characteristic of such sheet materials is maintaining their stable adhesion strength over an extended period. Adhesion testing serves as a crucial method for assessing the long-term adhesion performance. However, a standardized test method, including equipment and criteria, for directly measuring the adhesion strength of waterproofing sheets applied to onsite concrete walls has not yet been established. Therefore, reliance on laboratory evaluation results has been the only option thus far. In this study, a field-applicable adhesion measurement device was developed in an effort to provide a quality control method for self-adhesive waterproofing sheets and to demonstrate the validity of a standardized evaluation method utilizing this device. The developed adhesion measurement device was designed based on the principle of the peel-out test in compliance with the requirements outlined KS F 4934, where the test specimen backing plate can slide into a 1:1 ratio at the same distance as the rise of the tension jig when the tension jig is raised at a 45° angle. By utilizing this device, the adhesion strength values of self-adhesive waterproofing materials applied in the field were compared with those obtained using a laboratory universal testing machine (Salem, MA, USA) (UTM) on the test specimens. Comparative analysis yielded that the standard deviation of the results varied for the tested waterproofing materials, and the overall standard deviation for the UTM measurements was 0.17, while it was 0.18 for the portable field measurement equipment. The results of the comparison indicated that when limited to the scope of the KS measurement method specifications, the possibility for a wider scope of usage can be made possible with more data and studies. [ABSTRACT FROM AUTHOR]

In this study, the relationship between viscosity of synthetic polymer rubberized gel (SPRG) used for waterproofing and adhesive strength on varying degrees of wetted surfaces is examined. First, SPRG specimens of different ratios of viscosity modifiers were prepared (3% to 10%, interval of 1% per specimen type). These specimens were installed onto substrate surfaces of varying degrees of humidity ratio (0%, 10%, 20%, 30%, 50%, 70% and 100%). Upon following the standard installation procedure of the SPRG specimens, standard pull-off tests were conducted. Results of the test showed that a consistent relationship exists between the viscosity of synthetic polymer rubberized gel (SPRG) and its adhesive strength on different degrees of wetted surfaces. Linear regression analysis and subsequent calculation of the respective coefficient of determination leads to the result that viscosity is a relevant factor for achieving stable adhesion when it comes to the usage of SPRG waterproofing. The findings of this study could have significant implications for the development and application of adhesive gel waterproofing materials in various industries. [ABSTRACT FROM AUTHOR]

An in-situ analysis of local strain accommodation on transformation induced plasticity (TRIP) aided multi-phase steel was performed with a correlative application of characterization techniques such as digital image correlation (DIC), electron backscatter diffraction (EBSD), and micro-mechanical testing. The local strain on the complex microstructure of the multi-phase steel was measured during a tensile test using an innovative DIC method (which does not employ artificial patterns), in conjunction with a scanning electron microscope. The constituent phases of the examined surface were identified by postprocessing implemented on the EBSD maps. This was further verified by nano-indentation, consequently enabling systematic and quantitative analyses of the strain partitioning between the phases. Soft acicular ferrite accommodated the largest strain with sites of intense strain localization around the hard, neighboring martensite. The retained austenite transformed gradually into martensite because of the applied strain and caused strain localization in the neighboring acicular ferrite. This verified that DIC method proposed in this study enables precise and effective data collection at the interfaces between different phases that could have certainly been blocked by the DIC patterns in the conventional method. [ABSTRACT FROM AUTHOR]

Facility walls with high relative humidity, such as bathrooms or kitchens installed with tiles by spot-bonding methods, become far more prone to defect or adhesion failure when using large or heavy tiles and insufficient application area of adhesive but is still continued to be practiced due to their low costs in the material. Most importantly, if this practice is to be continued, the changes in adhesion strength of the tiles based on different adhesive application areas of adhesives must be clarified such that the very least secure application can be achieved even by using spot-bonding methods. In this regard, an experiment was conducted in this study where tile-adhered specimens with different adhesive-applied area ratios (AR) of 60 ± 2%, 80 ± 2%, and 100% were prepared. Tile adhesion strength was subsequently measured, after sectioning the entire surface of the tile into 40 pieces. Experimental results showed that the adhesion strength above the standard criteria could be achieved for about 75% of the entire tile with AR 100% conditioning, followed by 30% of the entire tile with AR 80 ± 2% conditioning, and 20% of the entire tile for AR 60 ± 2% conditioning. Further analysis showed that with AR 80 ± 2% and AR 60 ± 2% conditions, the overall adhesion strength decreased by the range of about 59–67% compared to the AR 100% application conditions. The results of the study intended to provide an analytical basis of guidelines and risks with the potential usage of spot-bonding and should only be used if AR 100% application is planned. [ABSTRACT FROM AUTHOR]

We present a technique for measuring the interfacial fracture energy, Γi, between a hard thin film and a soft substrate. A periodic array of hard thin islands is fabricated on a soft substrate, which is then subjected to uniaxial tension under an optical microscope. When the applied strain reaches a critical value, delamination between the islands and the substrate starts from the edge of the islands. As the strain is increased, the interfacial cracks grow in a stable fashion. At a given applied strain, the width of the delaminated region is a unique function of the interfacial fracture energy. We have calculated the energy release rate driving the delamination as a function of delamination width, island size, island thickness, and applied strain. For a given materials system, this relationship allows determination of the interfacial fracture energy from a measurement of the delamination width. The technique is demonstrated by measuring the interfacial fracture energy of plasma-enhanced chemical vapor deposition SiNx islands on a polyimide substrate. We anticipate that this technique will find application in the flexible electronics industry where hard islands on soft substrates are a common architecture to protect active devices from fracture. [ABSTRACT FROM AUTHOR]

Advances in modern electronic technologies have been driven toward combining the continued miniaturization of device components and their deterministic integration onto unconventional platforms. This effort aims at achieving electronic devices of various form factors with exotic functionalities, which has been foreseen to be impossible with any traditional approaches. Amongst a variety of 'futuristic' technologies, mechanically reconfigurable devices which can be reversibly stretched, twisted, and folded under severe mechanical deformation and harsh operational conditions offer an enormous amount of unprecedented opportunities. Traditional device manufacturing schemes have relied on three-dimensional silicon (Si)-based wafers, which are intrinsically bulky and rigid, requiring highly complicated and unstainable fabrication steps for the inclusion of such mechanical deformability. This fundamental challenge invokes innovations in materials design and processing, triggering to explore a new type of electronic materials that can intrinsically possess superior materials properties even at extremely small length-scales. Recently discovered two-dimensional (2D) transition metal dichalcogenides (TMDs) offer a rich set of unparalleled properties in a wide range of optical, electrical, and mechanical aspects unattainable with Si. Moreover, they offer uniquely suited advantages for mechanically reconfigurable electronics owing to their extremely large mechanical tolerance and small thickness coupled with van der Waals attraction-enabled relaxed assembly requirement. In this review, we report an extensive overview of up-to-date progress in exploring 2D TMD layers for mechanically reconfigurable electronic devices, particularly focusing on large-area devices by noting their technological and practical relevance. We systematically overview the material property suitability of 2D TMD layers for reconfigurable electronics and their fabrication and integration strategies as well as proof-of-concept demonstrations available in the literature. We also discuss current technical challenges associated with developing high-performance 2D TMD-based devices and offer forward-looking perspectives for this emerging technology. [ABSTRACT FROM AUTHOR]

Applications of nano-sized cellulose, such as use in tissue bio-scaffolds and drug delivery, have gained much attention in medical research. However, there are only a few studies reporting the skin toxicity of nano-sized cellulose. Here, we investigated the skin toxicity of plasma-induced nanostructured cellulose (PINC) in vitro and in vivo. Morphology of the PINC as well as that of human foreskin fibroblast (Hs27) and immortalized human keratinocyte (HaCaT) cell lines cultured on PINC were analyzed by scanning electron microscopy. The in vitro cytotoxicity of the material was evaluated using Hs27 and HaCaT cell lines and a reconstructed human epidermis model. For in vivo skin toxicity testing, after attaching the PINC to the dorsal skin of Sprague–Dawley rats, skin irritation was evaluated visually and histologically. Our results showed no cytotoxicity of PINC, which did not induce apoptosis or necrosis in either type of cells tested. PINC also did not stimulate irritation on rats in vivo, and no significant inflammatory responses were observed by histological analysis. These results indicate that PINC has no significant skin toxicity in vitro or in vivo. The absence of skin toxicity in PINC suggests that it can be used for skin-related applications without any harm. [ABSTRACT FROM AUTHOR]

We perform in-situ uniaxial tensile tests on polyimide substrates with patterned ceramic islands. The islands fail by either channel cracking or debonding from the substrate, depending on island size and thickness. To understand why different failure modes occur, we have analyzed the fracture and debonding of stiff islands on deformable substrates. Using finite element simulations, we find that the maximum tensile strain in the islands increases with island size, but decreases with island thickness. The maximum energy release rate for island/substrate debonding, in contrast, increases with both island size and thickness. Assuming that the islands do not fracture if the maximum tensile strain in the islands is lower than a critical value and that no debonding occurs if the maximum energy release rate is smaller than the interfacial toughness, the critical substrate strains for island fracture and debonding can be calculated. If the islands are thick and small, the critical debonding strain is small, and the islands fail by debonding. If the islands are large and thin, the critical fracture strain is small, and the islands fail by channel cracking. When the two critical strains are similar, debonding and cracking are expected to co-exist. Experimental observations confirm these findings. [ABSTRACT FROM AUTHOR]

Tetrahedral amorphous carbon (ta-C) film was prepared by the filtered vacuum arc process with Ar background gas. The residual compressive stress of the film decreased significantly as the Ar flow rate increased, whereas negligible change in the mechanical properties was observed. Structure analysis by Raman spectroscopy, near edge x-ray absorption fine structure, and electron spin resonance spectra revealed a close relationship between the residual compressive stress and the bond distortion that invokes paramagnetic defects or unpaired π electrons. These results demonstrate that the stress reduction can occur by relaxation of the distorted or twisted atomic bonds at the same fraction of sp3 hybridized bonds, which enhances the stability of the ta-C coating without deterioration in the advantageous properties. The effect of Ar background gas is discussed in terms of the increased ion population of low kinetic energy in the plasma beam. [ABSTRACT FROM AUTHOR]

Leakage in below-grade concrete structures are repaired using various types of grout-injection materials, but the selection of optimal material types with a consideration of the environmental degradation factors are not conducted. Different degradation factors can act on the waterproofing membranes or grout-injection materials simultaneously. Especially in the early stages of installation, the injected grout materials in the cracks for leakage repair or for reforming damaged waterproofing layers are subject to complex forms of degradation factors. In such cases, physical property changes to the materials can reduce the waterproofing performance of the grout-injection materials. In this study, a technical evaluation regime is proposed for selecting the optimal repair material to be used in underground concrete structure leakage cracks. In this study, six environmental degradation factors (thermal stress, chemical corrosion, erosion due to ground water flow, hydrostatic pressure, substrate movement, and humidity on concrete surface) are identified. Corresponding evaluation methods based on the ISO TS 16774 test method series were used for each factor to assess the performance evaluation of four different types of grout-injection materials (acrylic resin, epoxy resin, polyurethane foam, and synthetic polymerized rubber gel). Based on the test results, a new comprehensive evaluation regime is presented that allows a quantitative performance comparison between each type of grout-injection material. [ABSTRACT FROM AUTHOR]

In this paper, we studied the intergranular interaction in realistically shaped grains which have convex vacuum surface. The convex surface is evaluated by utilizing the SURFACE EVOLVER, a software package for grain growth simulation. Various shapes of grains are obtained by changing the wetting angles between the top surface and the grain boundaries. From finite element micromagnetic simulations, which are used to simulate the magnetization reversal in the simple granular structure, it is found that the exchange field decreases with increasing wetting angle. We studied the effect of the intergranular exchange and the magnetostatic interactions individually. In order to study the intergranular exchange coupling effect quantitatively, an analytic energy surface model for the exchange coupled system is developed. The results agree very well with those of micromagnetic simulation. Magnetostatic interactions reduce the exchange field by making the antiparallel state more favorable than the parallel. [ABSTRACT FROM AUTHOR]

As opposed to asphalt emulsion waterproofing membrane, Synthetic Rubber Polymer Gel (SPRG) waterproofing materials are not heated prior to installation in concrete structures. SPRG materials are typically required to undergo a screw-mixing process to temporarily reduce the high viscosity and facilitate membrane installation on a concrete surface. However, there is no standard regulation on the duration of screw-mixing time during SPRG construction. Reported construction cases indicate that SPRG are left under constant screw mixing and are reused after hours or days of rest without being replaced with fresh products. When installed in this condition, SPRGs are subject to waterproofing performance degradation. In this study, SPRG viscosity properties are measured after five different screw-mixing procedures (no screw mixing, 10, 20, 30 and 60 min) and are set to rest in storage (2 h, 1, 2, 3, and 7 days). Specimens prepared under the respective screw mixing and storage times are evaluated for their changes in waterproofing properties through a series of ISO TS 16774 standard evaluation methods. A correlative comparison of the property evaluation results is presented to provide the changes to SPRG property and waterproofing performance. These results are then used to propose a general guideline for selecting optimal screw-mixing time with respect to maintaining adequate waterproofing performance and the viscosity recovery property of SPRG. [ABSTRACT FROM AUTHOR]

Abstract: Heterogeneously integrated 2D van der Waals (vdW) solids composed of compositionally distinct atomic layers are envisioned to exhibit exotic electrical/optical properties unattainable with their monocomponent counterparts. However, the underlying principle for their morphology‐controlled chemical vapor deposition (CVD) growth and its associated growth variables have not been clarified, leaving their projected technological opportunities far from being realized. Herein, by employing tungsten trioxide (WO3) nanowires as a model system that uniquely enables the detailed atomic‐scale inspections of 2D/2D interfaces, the CVD growth mechanism of 2D molybdenum/tungsten disulfide vdW vertical stacks is studied. By employing extensive transmission electron microscopy (TEM) characterization, an intriguing growth mode transition is identified in these materials, i.e., 2D/2D layer‐by‐layer horizontal epitaxy to 2D/3D vertical layer reorientation, and it is confirmed that it is driven by varying 2D layer numbers. Corroborating molecular dynamics simulations clarify that the internal strain accumulated during the course of 2D layers growth dictates the final growth mode, further supported by TEM strain map analysis. This study not only sheds a new insight on better understanding the growth principles for 2D vdW heterostructures but also offers important technical guidance on tailoring their functionalities toward exploring 2D/2D heterojunction devices. [ABSTRACT FROM AUTHOR]

Synthetic Polymer Rubber Gels (SPRG) are used in Composite Modified Bituminous Waterproofing (CMBW) systems for waterproofing in concrete structures. A problem with the current design of SPRG is that when the emulsion breaks, the segregated oil layer can percolate through concrete cracks and cause oil leakage. This study proposes a new evaluation method which assesses the practical performance of SPRG products by testing their susceptibility to filler content settlement and oil leakage. Eight SPRG products used in Korea were used to demonstrate this evaluation method. Each product was installed in a concrete substrate specimen with an artificial crack made in the specimen’s bottom substrate. The specimens were observed for 28 days, and mass of leaked oil, total duration of leakage, average rate of sedimentation, and rheological threshold of initial leakage point were examined as part of the evaluation criteria. [ABSTRACT FROM AUTHOR]

Pseudocapacitive materials offer an opportunity to bridge the energy storage gap between supercapacitor and battery technologies. Herein is chronicled the first report of pseudocapacitance in a system devoid of liquid electrolytes, using the cathode material LiTiS2. It is demonstrated that due to extreme crystallite reduction to less than 3 nm, additional charge storage is derived by reducing surface Ti3+ to Ti2+ at higher voltages and more reversibly than traditionally shown. Due to facile diffusion pathways in 3-fold coordinated lithium along the TiS2 surfaces, disordered LiTiS2 can be used as a singular cathode without conductive additives. The result is a system exhibiting nearly 300 mA h g−1 at a rate of C/2 for 1000 cycles. Whereas active materials in liquid cells typically have size limitations before irreversibilities appear, the high pseudocapacitance demonstrated in this report indicates that active materials used in the solid-state could benefit from size reduction. Hopefully, a new avenue of research stems from this work to investigate mixed conductor nano-domains for solid-state battery/capacitor hybrids. The prospect of a solid-state pseudocapacitor unlocks a series of new applications that offer long shelf life, high temperature capabilities, and enhanced safety. [ABSTRACT FROM AUTHOR]

We propose that the Ni2O3 phase is the conducting filament in a unipolar NiO resistive switching system. The NiO film was grown by pulsed laser deposition using platinum top and bottom electrodes. Electron diffraction and high-resolution transmission electron microscopy were used to explore the microstructure. This system had forming-free properties, which suggested that the filaments were introduced in the pristine state. The Ni2O3-phase nanostructures were connected and disconnected in the pristine- and OFF-state samples, respectively, which implied that the phase acted as the conducting channel. X-ray photoemission spectroscopy results showing Ni3+ bonding in the pristine-state film support the importance of the Ni2O3 phase in the switching. Observed Ni2O3 phase (indicated by the red line) in the low resistance state of a pristine sample. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of plasma-enhanced deposition of an organosilane and benzene on resin bonding to a dental zirconia ceramic. A total of 70 zirconia specimens, which were polished before sintering, were randomly divided into five groups according to surface treatments before applying a dental adhesive (each group, n = 14): group 1, no previous treatment (control); group 2, plasma deposition with tetramethylsilane ( TMS); group 3, plasma deposition with benzene; group 4, sequential plasma deposition with TMS and benzene; and group 5, a zirconia primer (Z-Prime Plus). A dental adhesive (Scotchbond Multi-Purpose adhesive) was applied to the surface-treated zirconia, and resin composite rods were built in to enable shear bond-strength testing. The sequential deposition of TMS and benzene showed the highest bond strength [22.7 ± 3.7 MPa (mean ± SD)], approximately twice that of Z-Prime Plus (10.3 ± 3.2 MPa). The plasma deposition with either TMS or benzene also significantly improved bond-strength values compared with the negative-control group, and their effects were not statistically different from that of Z-Prime Plus. Following plasma deposition with TMS, the introduction of silicon-oxygen-zirconium (Si-O-Zr) bonds on the zirconia surface was confirmed via X-ray photoelectron spectroscopy ( XPS) analysis. Transmission electron microscopy and energy dispersive X-ray spectroscopy showed that a silica-like layer and a polymerizable carbon-rich layer were formed through sequential deposition with TMS and benzene. [ABSTRACT FROM AUTHOR]

We have developed a fast solid state Li ion conductor composed of LiBH4 and SiO2 by means of interface engineering. A composite of LiBH4–SiO2 was simply synthesized by high energy ball-milling, and two types of SiO2 (MCM-41 and fumed silica) having different specific surface areas were used to evaluate the effect of the LiBH4/SiO2 interface on the ionic conductivity enhancement. The ionic conductivity of the ball-milled LiBH4–MCM-41 and LiBH4–fumed silica mixture is as high as 10−5 S cm−1 and 10−4 S cm−1 at room temperature, respectively. In particular, the conductivity of the latter is comparable to the LiBH4 melt-infiltrated into MCM-41. The conductivities of the LiBH4–fumed silica mixtures at different mixing ratios were analyzed employing a continuum percolation model, and the conductivity of the LiBH4/SiO2 interface layer is estimated to be 105 times higher than that of pure bulk LiBH4. The result highlights the importance of the interface and indicates that significant enhancement in ionic conductivity can be achieved via interface engineering. [ABSTRACT FROM AUTHOR]

A new concept of pairing an active material and a mixed conductor is explored as a solid-state battery electrode. By imbedding nano-FeS2 domains into an amorphous LiTiS2 matrix, a hybrid power-energy system is achieved while additionally improving upon many common solid electrode design flaws. High-resolution transmission electron microscopy is used to probe the active material/mixed conductor interface over the course of cycling. Arguably the most beneficial development is enhancement of charge transfer, manifesting in a significantly increased exchange current as captured in a Tafel analysis. By developing a solution to active material isolation and creating a more homogenous electrode design, cycling at a high rate of C/2 for 500 cycles is obtained. Additionally, the electrode can recover full capacity simply by reducing system rate. Capacity recovery implicates a lack of active material isolation, a common problem in solid-state batteries. [ABSTRACT FROM AUTHOR]

We fabricated ZnS/diamond-like carbon (DLC) core-shell heterostructure nanowire using a simple two-step process: the vapor-liquid-solid method combined with radio frequency plasma enhanced chemical vapor deposition (rf PECVD). As a core nanowire, ZnS nanowires with face-centered cubic structure were synthesized with a sputtered Au thin film, which exhibit a length and a diameter of ~10 μm and ~30–120 nm . After rf PECVD for DLC coating, The length and width of the dense ZnS/DLC core-shell nanowires were a range of ~10 μm  and 50–150 nm , respectively. In addition, ZnS/DLC core-shell nanowires were characterized with scanning transmission electron microscopy. From the results, the products have flat and uniform DLC coating layer on ZnS nanowire in spite of high residual stress induced by the high sp3 fraction. To further understanding of the DLC coating layer, Raman spectroscopy was employed with ZnS/DLC core-shell nanowires, which reveals two Raman bands at 1550 cm−1 (G peak) and 1330 cm−1 (D peak). Finally, we investigated the optical properties from ultraviolet to infrared wavelength region using ultraviolet-visible (UV-Vis) and Fourier transform infrared (FT-IR) spectrometry. Related to optical properties, ZnS/DLC core-shell nanowires exhibit relatively lower absorbance and higher IR transmittance than that of ZnS nanowires. [ABSTRACT FROM AUTHOR]

Non-thermal atmospheric pressure plasmas ( NT- APPs) have been shown to improve the bond strength of resin composites to demineralized dentin surfaces. Based on a wet-bonding philosophy, it is believed that a rewetting procedure is necessary after treatment with NT- APP because of its air-drying effect. This study investigated the effect of 'plasma-drying' on the bond strength of an etch-and-rinse adhesive to dentin by comparison with the wet-bonding technique. Dentin surfaces of human third molars were acid-etched and divided into four groups according to the adhesion procedure: wet bonding, plasma-drying, plasma-drying/rewetting, and dry bonding. In plasma treatment groups, the demineralized dentin surfaces were treated with a plasma plume generated using a pencil-type low-power plasma torch. After the adhesion procedures, resin composite/dentin-bonded specimens were subjected to a microtensile bond-strength test. The hybrid layer formation was characterized by micro-Raman spectroscopy and scanning electron microscopy. The plasma-drying group presented significantly higher bond strength than the wet-bonding and dry-bonding groups. Micro-Raman spectral analysis indicated that plasma-drying improved the penetration and polymerization efficacy of the adhesive. Plasma-drying could be a promising method to control the moisture of demineralized dentin surfaces and improve the penetration of adhesive and the mechanical property of the adhesive/dentin interface. [ABSTRACT FROM AUTHOR]

To date, most coating layers for electrode materials for Li-ion batteries have been fabricated using the sol–gel method or atomic layer deposition (ALD), which involve complicated processing steps and limited candidates for coating materials. With an emphasis on solving these issues, herein, a new coating methodology based on a sputtering system was developed, and sputtered zirconium oxide was coated on Li(Ni1/3Co1/3Mn1/3)O2 (L333) cathode powders. The continuous movement of the cathode powders during the coating procedure and the high kinetic energy from the sputtering process resulted in a highly uniform coating layer with multiple structures exhibiting a concentration and valence state gradient of Zr, i.e., surface (mainly Zr4+) and doped (mainly Zr2+) layers. The ZrOx-coated L333 powders exhibited an outstanding capacity retention (96.3% at the 200th cycle) and superior rate capability compared with the uncoated version in a coin cell with 1 M LiPF6 in EC : DEC liquid electrolyte. The ZrOx-coated L333 powders also exhibited an enhanced specific capacity in a solid state battery cell with a sulfide-based inorganic solid-state electrolyte. The improved electrochemical performance of ZrOx/L333 was attributed to the synergetic effect from the surface and doped layers: physical/chemical protection of the active material surface, enhancement of Li-ion diffusion kinetics, and stabilization of the interfaces. [ABSTRACT FROM AUTHOR]

Natural cubic‐FeS2 is embedded in a stabilized polyacrylonitrile (PAN) matrix. The PAN matrix confines the electroactive reduced species of FeS2 and captures intermediate polysulfide and elemental iron to prevent their dissolution into the electrolyte. The formation of orthorhombic‐FeS2 is observed at full charge, which is consistent with previous studies. [ABSTRACT FROM AUTHOR]

Dynamic recrystallization (DRX) of 99.9999% aluminum single crystal at room temperature was examined under frictionless deformation mode. To exclude the self-heating of the specimen due to applied high strain, a microcrack that localizes the stress at a very small region was intentionally introduced by controlled local necking. For the in situ observation of DRX, a specially designed in situ microdeformation device was positioned inside an electron backscattered diffraction system chamber. Recrystallized grains showed relatively random texture and preferred growth direction. The subgrains with low-angle grain boundaries formed by dynamic recovery transformed into small grains with high-angle grain boundaries, acting as nuclei for discontinuous dynamic recrystallization and growing by further deformation. The DRX in pure aluminum can take place under frictionless tensile deformation conditions at room temperature, and the stress localization and high purity are key issues for the DRX of aluminum at room temperature. [ABSTRACT FROM AUTHOR]

Cyclized‐polyacrylonitrile (cyclized‐PAN) is used as a conformal coating on nano‐Si for highly reversible anodes. Cyclization of PAN proceeds by limiting the pyrolysis to 300 °C such that the cyclized‐PAN maintains its polymeric properties while also providing sp2 π bonding for good electronic conductivity. Cyclized‐PAN is thus a conjugated polymer with good mechanical resiliency to accommodate Si's volumetric expansion and also good mixed conductivity. [ABSTRACT FROM AUTHOR]

We report that a solid-state battery architecture enables the reversible, four electron storage of fully utilized solvothermally synthesized cubic-FeS2 (pyrite). With a sulfide based glass electrolyte we successfully confine electro-active species and permit the safe use of a lithium metal anode. These FeS2/Li solid-state cells deliver a theoretical specific capacity of 894 mAh g−1 at 60 °C. We find that nanoparticles of orthorhombic-FeS2 (marcasite) are generated upon recharge at 30-60 °C which explains a coincident change in rate kinetics. [ABSTRACT FROM AUTHOR]

The evolution of ion-beam induced surface roughening of PMMA was investigated using an anode-layer ion beam source with O2, Ar, and their mixture. Use of the O2 ion beam created rough granular patterns on the surface of PMMA because O2 ions could break the CC backbone and subsequently combine with the broken C bonds, resulting in local cross-linking and aggregation. However, the Ar ion beam tended to reduce the surface roughness due to the decomposition of the oxygen-containing ester groups (OCH3 and OCO) and the increase of an overall cross-linking of the amorphous carbon layer, which played a role in etch resistance and suppression of polymer mobility as well as aggregation on the modified PMMA surface. By varying the ratio of Ar over O2, the surface morphology of PMMA was modified to exhibit features ranging from granular roughness to crater-like features. [ABSTRACT FROM AUTHOR]