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A hybrid supercapacitor/battery device is proposed by integrating Na3V2(PO4)2F3 and multi‐walled carbon nanotubes as the battery electrode and carbon nanofiber as a supercapacitor electrode. The device made via the slurry casting of electrode material on foldable thin nickel foils leads to a robust, mechanically flexible sodium‐ion capacitor/battery (supercapattery) as a hybrid energy storage system. The device exhibits a specific capacitance of 136 F g−1 with a corresponding specific capacity of 95 C g−1 at a potential scan rate of 1 mV s−1, a maximum working voltage of 0.70 V, and a power density of 15 kW kg−1 at 2.50 Wh kg−1. Mechanical flexibility tests show practically unperturbed electrochemical properties at significant bending angles of up to 160°, indicating excellent robustness during large‐scale device deformation. The current study offers new avenues to develop energy storage systems for next‐generation portable and wearable energy storage devices that can be integrated into a variety of platforms. [ABSTRACT FROM AUTHOR]

In this Letter, low-temperature (400 °C) chemical vapor deposition-grown boron nitride (BN) was investigated as the gate dielectric for AlGaN/GaN metal–insulator–semiconductor high electron mobility transistors (MISHEMTs) on a Si substrate. Comprehensive characterizations using x-ray photoelectron spectroscopy, reflection electron energy loss spectroscopy, atomic force microscope, high-resolution transmission electron microscopy, and time-of-flight secondary ion mass spectrometry were conducted to analyze the deposited BN dielectric. Compared with conventional Schottky-gate HEMTs, the MISHEMTs exhibited significantly enhanced performance with 3 orders of magnitude lower reverse gate leakage current, a lower off-state current of 1 × 10−7 mA/mm, a higher on/off current ratio of 108, and lower on-resistance of 5.40 Ω mm. The frequency-dependent conductance measurement was performed to analyze the BN/HEMT interface, unveiling a low interface trap state density (Dit) on the order of 5 × 1011–6 × 1011 cm−2 eV−1. This work shows the effectiveness of low-temperature BN dielectrics and their potential for advancing GaN MISHEMTs toward high-performance power and RF electronics applications. [ABSTRACT FROM AUTHOR]

Cellulose modification often employs chemical processes to tailor its properties and functionalities to fit the demands of a wide range of applications, maximizing its potential as a versatile and sustainable material. From both synthetic and environmental standpoints, one of the ultimate goals is to achieve significant modifications to enhance the end properties of the cellulose while minimizing the number of modified building blocks. The current study demonstrates that a synthetic glucose derivative, 6‐deoxy‐6‐fluoro‐glucose (6F‐Glc), fed into the fertilized cotton ovules, resulted in the accumulation of fluorine inside the cotton fibers with no apparent alteration to their morphology or development. These fibers exhibited a degree of substitution of 0.006, which is 170 times lower than that reported for chemical methods for cellulose modification. However, the physical characterization of the modified fibers showed a surprisingly large impact of this low‐level modification on the cellulose structure (e.g., hydrogen bonding network rearrangement) and a modest increase in the mechanical properties of the fibers. The obtained results exemplify the use of biological systems to introduce low quantities of new functionalities while maximizing the impact on fiber properties. [ABSTRACT FROM AUTHOR]

Surface morphology, in addition to hydrophobic and electrostatic effects, can alter how proteins interact with solid surfaces. Understanding the heterogeneous dynamics of protein adsorption on surfaces with varying roughness is experimentally challenging. In this work, we use single-molecule fluorescence microscopy to study the adsorption of α-lactalbumin protein on the glass substrate covered with a self-assembled monolayer (SAM) with varying surface concentrations. Two distinct interaction mechanisms are observed: localized adsorption/desorption and continuous-time random walk (CTRW). We investigate the origin of these two populations by simultaneous single-molecule imaging of substrates with both bare glass and SAM-covered regions. SAM-covered areas of substrates are found to promote CTRW, whereas glass surfaces promote localized motion. Contact angle measurements and atomic force microscopy imaging show that increasing SAM concentration results in both increasing hydrophobicity and surface roughness. These properties lead to two opposing effects: increasing hydrophobicity promotes longer protein flights, but increasing surface roughness suppresses protein dynamics resulting in shorter residence times. Our studies suggest that controlling hydrophobicity and roughness, in addition to electrostatics, as independent parameters could provide a means to tune desirable or undesirable protein interactions with surfaces. [ABSTRACT FROM AUTHOR]

Quasi‐2D hybrid halide perovskites have drawn considerable attention due to their improved stability and facile tunability compared to 3D perovskites. The expansiveness of possibilities has thus far been limited by the difficulty in incorporating large ligands into thin‐film devices. Here, a bulky bi‐thiophene 2T ligand is focused on to develop a solvent system around creating strongly vertically‐aligned (2T)2(MA)6Pb7I22 (n = 7) quasi‐2D perovskite films. By starting with a poorly coordinating solvent (gamma‐butyrolactone) and adding a small amount of dimethylsulfoxide and methanol, it is found that vertical orientation and z‐uniformity is greatly improved. These are carefully examined and verified using grazing‐incidence wide‐angle X‐ray scattering analysis and advanced optical characterizations. These films are incorporated into champion solar cells that achieve a power conversion efficiency of 13.3%, with a short‐circuit current density of 18.9 mA cm‐2, an open‐circuit voltage of 0.96 V, and a fill factor of 73.8%. Furthermore, the quasi‐2D absorbing layers show excellent stability in moisture, remaining unchanged after hundreds of hours. In addition, 2T is compared with the more common ligands butylammonium and phenylethylammonium in this solvent system to develop heuristics and deeper understanding of how to incorporate large ligands into stable photovoltaic devices. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate intermediate treatments between sodium hypochlorite and chlorhexidine gluconate irrigations for the prevention of a toxic brown precipitate in root canal therapy. Materials and Methods: Thirty‐nine premolars were irrigated with 6% sodium hypochlorite and divided into either: No intermediate treatment; Dry paper points; three different irrigations with 17% ethylenediaminetetraacetic acid, deionized water, or 5% sodium thiosulfate. 2% chlorhexidine gluconate was the final irrigant in all groups. Sectioned teeth were analyzed for brown precipitate intensity and area using stereomicroscopy and components related to para‐chloroaniline using Time‐of‐Flight Secondary Ion Mass Spectrometry (ToF‐SIMS). Results: Stereomicroscopy showed that 5% STS significantly reduced brown precipitate intensity and area as compared with no intermediate irrigation (p <.05, Chi‐square, generalized linear model, and Tukey's multiple comparison tests). Utilizing ToF‐SIMS, 5% sodium thiosulfate was most effective in reducing the components representing para‐chloroaniline and chlorhexidine gluconate. Conclusion: The 5% sodium thiosulfate was most effective among other intermediate treatments, assessed by stereomicroscopy and ToF‐SIMS. [ABSTRACT FROM AUTHOR]

We report a method to prepare core–shell zeolite beta (*BEA) with an aluminous core and an epitaxial Si‐rich shell. This method capitalizes on the inherent defects in *BEA crystals to simultaneously passivate acid sites on external surfaces and increase intracrystalline mesoporosity through facile post‐hydrothermal synthesis modification in alkaline media. This process creates more hydrophobic materials by reducing silanol defects and enriching the shell in silica via a combination of dealumination and the relocation of silica from the core to the shell during intracrystalline mesopore formation. The catalytic consequences of *BEA core–shells relative to conventional analogues were tested using the biomass conversion of levulinic acid and n‐butanol to n‐butyl levulinate as a benchmark reaction. Our findings reveal that siliceous shells and intracrystalline mesopores synergistically enhance the performance of *BEA catalysts. [ABSTRACT FROM AUTHOR]

This paper presents work on the heteroepitaxy of salts, specifically fluorides, on semiconductors and heteroepitaxy of semiconductors on salts. Fluorides layers are deposited on commercial Gallium Arsenide (GaAs) wafers followed by the heteroepitaxial growth of GaAs using metal‐organic chemical vapor deposition (MOCVD). The fluoride layers consist of 2 lattice‐engineered layers of alkaline‐earth compounds to match with GaAs, and are used to sandwich another alkaline‐earth compound with higher water‐solubility as a sacrificial layer. The triple fluoride layers enable liftoff of free‐standing semiconductor films which can be further transferred to desirable substrates. 2D‐X‐ray Diffraction (2D‐XRD) measurements confirm epitaxial growth of both the fluorides and the subsequently grown GaAs films. Single junction (SJ) solar cell devices based on thus prepared films show a power conversion efficiency (PCE) of 10.3% under 1 sun illumination. After the completion of device fabrications, the GaAs film is lifted off from the substrate by a novel water‐assisted epitaxial liftoff (H2O‐ELO) technique and transferred to a cheaper substrate. The original GaAs wafer is recycled and reused twice. Devices based on reused substrates show no significant degradation in performance. The semiconductor‐salt‐semiconductor scheme has great implications in high‐performance, flexible, and large‐area electronics. [ABSTRACT FROM AUTHOR]

Aim: To investigate (1) the cytotoxic potential of the brown precipitate (BP) formed with sodium hypochlorite (NaOCl) and chlorhexidine gluconate (CHX), using both a small animal model of Caenorhabditis elegans (C. elegans) and cultured human gingival fibroblasts; and (2) the chemical composition of BP using Time‐of‐Flight Secondary Ion Mass Spectrometry (ToF‐SIMS). Methodology: Brown precipitate was obtained by mixing equal volumes of 6% NaOCl and 2% CHX and separating the BP from clear supernatant by centrifugation. The brown precipitate was weighed and solubilized in dimethyl sulfoxide for cytotoxicity experiments. The cytotoxic effect of BP was assessed using C. elegans larvae and primary immortalized human gingival fibroblasts‐hTERT (hTERT‐hNOF) cells. Various dilutions of BP (25 ng/µL–150 ng/µL), supernatant (0.15% v/v), NaOCl (1:100–1:1000 dilutions of 6% NaOCl) or CHX (1:500–1:1000 dilutions of 2% CHX) along with vehicle control (0.5% v/v ethanol and 0.15% v/v DMSO) or untreated control (growth medium) were tested on C. elegans larvae and hTERT‐hNOF cells. Viability was assessed in C. elegans larvae using stereomicroscopy and in hTERT‐hNOF cells using dehydrogenase‐based colorimetric assay. ToF‐SIMS was used to assess the chemical composition of BP in comparison with CHX and para‐chloroaniline (PCA). The C. elegans and cell line data were analysed using Log‐Rank test and Student's t‐test, respectively (p <.05). Results: BP‐75 ng/µL and BP‐150 ng/µL were significantly more toxic to C. elegans larvae than the untreated, vehicle, supernatant or CHX treatment groups (p <.0001). Similarly, in hTERT‐hNOF cells, BP‐50 ng/µL, BP‐75 ng/µL and BP‐150 ng/µL induced significant cytotoxicity within 2 h compared with untreated, vehicle, supernatant and CHX treatments (p <.05). ToF‐SIMS analysis of BP revealed ion composition characteristic of both CHX and the carcinogen PCA. Conclusions: Brown precipitate was toxic in both C. elegans larvae and hTERT‐hNOF cells. The ToF‐SIMS analysis of BP revealed ions characteristic of CHX and PCA that could account for the toxicities observed in C. elegans larvae and human gingival fibroblasts. Because of the insoluble and toxic nature of BP, consecutive use of CHX and NaOCl irrigants should be avoided in root canal treatment. [ABSTRACT FROM AUTHOR]

This article presents results on flexible high-temperature polycrystalline silicon (FHTPS) thin-film transistor (TFT) fabricated on metal foils. Metal foils eliminate processing temperature constraints which are rather stringent on flexible TFT devices fabricated on plastics and allow high-temperature post-crystallization annealing (PCA). The source/drain (S/D) area of the devices was doped by diffusion with a spin-coated solid source at high temperatures and this process also functioned as PCA to improve the quality of the active undoped area. Solid-phase crystallized TFTs with diffused S/D at 800 °C demonstrate saturation mobility ($\mu _{SAT}$) of 103 cm2/ $\text{V}\cdot \text{s}$ , an ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ratio of close to 106, a subthreshold swing (SS) of 498 mV/dec, and a threshold voltage (${V}_{TH}$) of 4.9 V. Technology computer-aided design (TCAD) simulations reveal that parasitic resistance accounts for most of the performance variations of devices diffused at different temperatures when the devices are turned on, and defect density is dominant in the subthreshold and the off regimes. The performance of the fabricated devices suffered only slight changes after 10 000 cycles of bending with 7 mm radius showing their mechanical robustness. [ABSTRACT FROM AUTHOR]

Structural coloration frequently originates from the interaction of light with multilayers of thin films in living organisms. One example where structural colors are created by multilayers is the jewel beetle, Chrysochroa fulgidissima, which has highly iridescent green elytra with longitudinal red stripes. We examine the structure, chemical information, and physical properties of the epicuticle of the jewel beetle by using atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nanoindentation, and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS). AFM and SEM were used to analyze the surface structures of the green elytra and red stripes of the jewel beetle's wing. SEM and TEM images obtained from the cross‐sectioned cuticle samples of green and red areas indicated that the color arises from interference reflectors and reflectors consist of successive repeating layers of different electronic densities. Nanoindentation results showed that the green area of the elytron possesses a higher hardness and reduced modulus compared with the red area. To analyze the surface of the elytra and to compare multilayers of the green area with those of the red area, mass spectra and depth profiles were acquired by ToF‐SIMS with C60 and Ar cluster ion beams. The epicuticle consists of several layers with alternating high and low abundances of inorganic and organic fragment ions, with approximately 16 layers in the green and 12 layers in the red area. Therefore, ToF‐SIMS combined with other analytical techniques indicate that multilayer reflection is a major mechanism of the jewel beetle's iridescence causing structural coloration. [ABSTRACT FROM AUTHOR]

Organic photovoltaic (OPV) devices offer a number of unique advantages over conventional single crystal silicon solar cells, such as simple and low‐cost fabrication, significantly reduced weight, high flexibility, and semitransparency. However, OPV devices exhibit poor durability to mechanical deformations. Here, the use of an elastic semi‐interpenetrating network is studied to improve the mechanical durability of the active layer of OPV devices based on the high‐performance poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl‐3‐fluoro)thiophen‐2‐yl)‐benzo[1,2‐b:4,5‐b′]dithiophene))‐alt‐(5,5‐(1′,3′‐di‐2‐thienyl‐5′,7′‐bis(2‐ethylhexyl)benzo[1′,2′‐c:4′,5′‐c′]dithiophene‐4,8‐dione)]:2,2′‐[[6,6,12,12‐tetrakis(4‐hexylphenyl)‐6,12‐dihydrodithieno[2,3‐d:2′,3′‐d′]‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐2,8‐diyl]bis[methylidyne(3‐oxo‐1H‐indene‐2,1(3H)‐diylidene)]]bis[propanedinitrile] donor:acceptor blend (PBDBT‐2F:ITIC). The elastic interpenetrating network is synthesized in situ through the UV photoinitiated crosslinking of thiol–ene additives in the active layer. The effects of strain as a function of bending on the network‐stabilized active layer structure are systematically investigated. The elastic interpenetrating network suppresses crack formation and improves durability to high‐curvature and repeated bending deformations. Performance measurements show that network‐stabilized devices outperform pristine devices above a critical bending strain and number of bending deformations. The photovoltaic performance in general decreases with the increase in the network content, and the best performing devices are obtained using network forming reagents that are most compatible with the donor:acceptor system. This work describes an effective route to flexible devices using semi‐interpenetrating polymer networks and provides insight into the design of the networks to maximize photovoltaic performance. [ABSTRACT FROM AUTHOR]