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MXenes, the largest family of 2D transition metal carbides/nitrides, have emerged as promising materials for various applications due to their exceptionally fascinating properties. In this study, the potential of MXenes is investigated in plasmonic applications, particularly focusing on surface‐enhanced Raman scattering (SERS) and broadband photodetection. The study explored a broader range of light‐matter interactions based on edge plasmons that emerge at sub‐monolayer coverage of MXene, while existing studies have primarily focused on thicknesses exceeding tens of nanometers. Additionally, by incorporating MXenes onto 3D trench nanostructures, To maximize their plasmonic properties is aimed by enhancing the manifestation of edge plasmons, leading to intensified light amplification. The fabricated opto‐electronic devices exhibit remarkable sensitivity in SERS detection, achieving a detection limit as low as ≈0.1 nm for the target dye molecule, significantly surpassing typical thresholds for non‐metal‐based detection. Additionally, the enhancement factor exceeds that of commercially available Au‐based SERS substrates. Furthermore, MXene‐based photodetectors demonstrate competitive photoresponsivity and response time, particularly toward the near‐infrared (NIR) wavelength bands, which are challenging to achieve with MXene‐based photodetectors. Through a comprehensive analysis, including electric field calculations, the mechanisms driving the observed enhancements are unveiled, primarily attributing them to edge plasmons. [ABSTRACT FROM AUTHOR]

Portable and personalized artificial intelligence (AI)‐driven sensors mimicking human olfactory and gustatory systems have immense potential for the large‐scale deployment and autonomous monitoring systems of Internet of Things (IoT) devices. In this study, an artificial Q‐grader comprising surface‐engineered zinc oxide (ZnO) thin films is developed as the artificial nose, tongue, and AI‐based statistical data analysis as the artificial brain for identifying both aroma and flavor chemicals in coffee beans. A poly(vinylidene fluoride‐co‐hexafluoropropylene)/ZnO thin film transistor (TFT)‐based liquid sensor is the artificial tongue, and an Au, Ag, or Pd nanoparticles/ZnO nanohybrid gas sensor is the artificial nose. In order to classify the flavor of coffee beans (acetic acid (sourness), ethyl butyrate and 2‐furanmethanol (sweetness), caffeine (bitterness)) and the origin of coffee beans (Papua New Guinea, Brazil, Ethiopia, and Colombia‐decaffeine), rational combination of TFT transfer and dynamic response curves capture the liquids and gases‐dependent electrical transport behavior and principal component analysis (PCA)‐assisted machine learning (ML) is implemented. A PCA‐assisted ML model distinguished the four target flavors with >92% prediction accuracy. ML‐based regression model predicts the flavor chemical concentrations with >99% accuracy. Also, the classification model successfully distinguished four different types of coffee‐bean with 100% accuracy. [ABSTRACT FROM AUTHOR]

Real‐world applications of graphene require reliable routes for synthesizing large‐area graphene and methods to tune its structural and electrical properties. A viable and facile route is presented for synthesizing 3D porous graphene (3PG) on PI films with tunable patterns and locations via the photon‐pen writing technique and subsequent oxygen plasma treatment. The laser power and scan speed are optimized for 3PG synthesis. The electrical properties and surface hydrophilicity are controlled via surface customization of 3PG with optimal oxygen plasma treatment duration and laser inter‐spacing. The capability of humidity sensors based on surface‐customized 3PG with hydrophobic surface is demonstrated. [ABSTRACT FROM AUTHOR]

Although the structural and electrical engineering of transition metal dichalcogenides using atomic doping or doping‐induced phase modulation can be used to attain high‐performance and wavelength‐tunable optoelectronic devices, accessible substitutional doping to overcome the large lattice mismatch between the host and guest atom‐related bonding states remains elusive. This study corroborates an innovative synthetic route for molybdenum disulfide (MoS2)‐derived two‐dimensional (2D) quaternary semiconductors substitutionally doped with Re and O using a solution‐based large‐area compatible approach combined with the thermal evaporation of dopants. The substitutional doping of Re into MoS2 crystals with a large lattice mismatch is effectively accomplished by adopting structurally unstable host films, resulting in the large‐scale synthesis of 2D quaternary multi‐layers with a Re doping concentration >10%. Comprehensive spectroscopic and microscopic evaluations are performed to determine the efficacy of the host films with structural instability for the synthesis of 2D RexMo(1‐x)O2yS2(1‐y) quaternary multi‐layers. The capability of the quaternary semiconductor for versatile nanophotonic devices is validated by ascertaining the simultaneous enhancement of the photoelectrical properties with wide‐range optical absorption and photoelectrochemical properties, as compared with those of their binary counterparts. [ABSTRACT FROM AUTHOR]

The van der Waals (vdW) heterojunctions of transition metal dichalcogenides (TMDCs) provide an advanced platform for interlayer exciton generation to detect the exceeding cutoff wavelengths of individual TMDCs. Herein, the first demonstration of high‐performance infrared (IR) photodetectors driven by interlayer excitons and based on HfS2/MoS2 vdW heterojunctions grown by chemical vapor deposition is presented. HfS2 exhibits selective growth only on MoS2, establishing a vertical heterojunction that effectively generates interlayer excitons. The synthesized HfS2/MoS2 vertical heterojunction with type‐II band alignment exhibits a low interlayer bandgap and a significantly large interface area, enabling highly efficient IR detection. Moreover, the built‐in potential in HfS2/MoS2 plays a pivotal role in the outstanding photoresponse by suppressing the dark current and providing gradient band bending for the interlayer exciton‐induced photocarriers to drift toward each electrode. The HfS2/MoS2 photodetector exhibits remarkable performance, achieving a detectivity (D*) of ≈7 × 1013 Jones at 1550 nm, D* of ≈2 × 1014 Jones at 980 nm, and fast response time of 60 µs, surpassing previously reported 2D photodetectors. Overall, the successful demonstration of a photodetector based on vdW epitaxial HfS2/MoS2 paves the way for the advancement of large‐scale high‐performance IR sensors. [ABSTRACT FROM AUTHOR]

Porosification of fluoride can be effectively utilized in various applications, based on its abundance of exposed active sites. However, previous approaches have drawbacks in terms of application in fields that require meticulous control over porosity. Herein, an innovative strategy is suggested for achieving precise porosity tuning using a micelle‐carried MgF2 precursor intermediate. As the size of the MgF2 precursor clusters increases through micellization, the sizes of the resulting solidified MgF2 grains and the intergranular voids between the grains increase. Controlled MgF2 with intergranular voids can achieve very low‐refractive indices (≈1.04) with extremely fine refractive index control intervals (0.01–0.04). By employing extreme controllability of refractive index, graded refractive index antireflective coating is applied to the quartz window, and an average transmittance of ≈97.96% (250–1100 nm) is obtained. Finally, the coating is applied to a perovskite half‐cell enabling a ≈22.46% increase in the light‐absorption efficiency. [ABSTRACT FROM AUTHOR]

Atomic layer deposition (ALD) has become the most widely used thin‐film deposition technique in various fields due to its unique advantages, such as self‐terminating growth, precise thickness control, and excellent deposition quality. In the energy storage domain, ALD has shown great potential for supercapacitors (SCs) by enabling the construction and surface engineering of novel electrode materials. This review aims to present a comprehensive outlook on the development, achievements, and design of advanced electrodes involving the application of ALD for realizing high‐performance SCs to date, as organized in several sections of this paper. Specifically, this review focuses on understanding the influence of ALD parameters on the electrochemical performance and discusses the ALD of nanostructured electrochemically active electrode materials on various templates for SCs. It examines the influence of ALD parameters on electrochemical performance and highlights ALD's role in passivating electrodes and creating 3D nanoarchitectures. The relationship between synthesis procedures and SC properties is analyzed to guide future research in preparing materials for various applications. Finally, it is concluded by suggesting the directions and scope of future research and development to further leverage the unique advantages of ALD for fabricating new materials and harness the unexplored opportunities in the fabrication of advanced‐generation SCs. [ABSTRACT FROM AUTHOR]

2D van der Waals (vdW) hetero integration, which features exotic interplanar interactions derived from mixed‐dimensional heterostructures, is an emergent platform for implementing high‐performance electronics and broadband/wavelength‐tunable photodetectors. However, the production of large‐area 2D spatially homogeneous transition‐metal dichalcogenides (TMDs) and elucidation of the electrostatic dynamics governing the interlayer interactions are two paramount prerequisites for realizing practical 2D‐TMD‐heterostructure‐based photodetectors. Here, a wafer‐scale synthesis of mixed‐dimensional Pt–MoS2‐based vdW heterostructures is unprecedentedly demonstrated by manipulating the platinization conditions. The rationally designed platinization yields dimensionality‐tailored Pt, including Pt nanofilm, Pt nanoparticles, and Pt atoms, with MoS2 as host platform. From density functional theory calculations, this study insights that Mo vacancy sites on the MoS2 surface are thermo‐dynamically favorable sites for Pt with an adsorption energy of −2.25 eV, then Pt clusters are sequentially formed neighboring the specific Pt‐substituted position with a formation energy of 1.30 eV. Intensive microscopic and spectroscopic analyses reveal the structural, chemical, and electrical features, validating the proposed dynamics‐related mechanism. The dimensionality‐tailored vdW heterostructures exhibit outstanding optoelectrical properties with excellent photoresponsivity (2.04 mA W−1) and highly sensitive detectivity (9.82 × 106 cm Hz1/2 W−1). [ABSTRACT FROM AUTHOR]

Despite the encouraging properties and research of 2D MoS2, an ongoing issue associated with the oxidative instability remains elusive for practical optoelectronic applications. Thus, in‐depth understanding of the oxidation behavior of large‐scale and homogeneous 2D MoS2 is imperative. Here the structural and chemical transformations of large‐area MoS2 multilayers by air‐annealing with altered temperature and time via combinatorial spectro‐microscopic analyses (Raman spectroscopy, X‐ray photoelectron spectroscopy, and atomic force microscopy) are surveyed. The results gave indications pertaining to temperature‐ and time‐dependent oxidation effects: i) heat‐driven elimination of redundant residues, ii) internal strain stimulated by the formation of MoO bonds, iii) deterioration of the MoS2 crystallinity, iv) layer thinning, and v) morphological transformation from 2D MoS2 layers to particles. Photoelectrical characterization of the air‐annealed MoS2 is implemented to capture the link between the oxidation behavior of MoS2 multilayers and their photoelectrical properties. The photocurrent based on MoS2 air‐annealed at 200 °C is assessed to be 4.92 µA, which is 1.73 times higher than that of pristine MoS2 (2.84 µA). The diminution in the photocurrent of the photodetector based on MoS2 air‐annealed above 300 °C in terms of the structural, chemical, and electrical conversions induced by the oxidation process is further discussed. [ABSTRACT FROM AUTHOR]

The effects of nitrogen film cooling on ignition transition under different conditions of film cooling injection pressure were observed. Gaseous oxygen and liquid kerosene were used as propellants, injected using a shear coaxial injector. Gaseous nitrogen as the film coolant was injected along the gap between the combustion chamber and outer injector walls. A dynamic pressure transducer and a high-speed camera with a band-pass filter were respectively used. The over-peak pressure and pressure rise time were detected in cases with film cooling. With the increase in the differential pressure, the over-peak pressure decreased, and pressure rise time increased. These phenomena are explained by the interruption of normal propellant injection in the mixing zone of propellant. The combustion instability intensity decreased with the increase in the differential pressure between the combustion chamber and injected film coolant. Flame structures were visualized to confirm the unstable combustion flame during the ignition transition. [ABSTRACT FROM AUTHOR]

The article in Advanced Functional Materials explores the plasmonic effect of 2D MXene for advanced photonic device applications. Researchers, including Min Seok Jang, Chi Won Ahn, and Yonghee Lee, investigate the use of MXenes integrated onto 3D trench nanostructures to enhance light-matter interaction at sub-monolayer thicknesses. The study demonstrates significant light amplification and improved optical characteristics, with vibrant colors and detailed graphics used to effectively communicate the research findings. [Extracted from the article]

The multilayer triboelectric nanogenerators (TENGs) are widely developed to enhance the output performance of device. However, these TENGs consisting of electron transfer, transport, trap layers toward a large volumetric charge density should be wearable and mass‐produced for commercialization. Thus, appropriate material selection in respective layers and fabrication method are crucial for the commercialization of multilayer TENG. This study presents all‐printed, sustainable wearable TENGs based on electron accumulation polymers (EAPs) with superior charge retention capability. The EAPs consisting of polytetrafluoroethylene (PTFE), carboxyl functionalized single‐walled carbon nanotubes (SWCNTs:COOH), and Ti3C2Tx (MXene) in a fluorinated polymer matrix, are used. Compared to the reference, the EAPs not only lead to approximately six times higher output performance (300 V and 40 µA) but also four times more sustainable charge retention capability (92%) for an hour. These are attributed to the three‐step electron‐trapping mechanism with electron transfer/transport from PTFE/SWCNT and electron trapping in MXene. In addition, TENGs with EAPs exhibit excellent mechanical stability and reliability with fascinating single‐electrode demonstrations. Finally, the TENG with EAPs can efficiently operate various portable electronics and pH monitoring systems with a pH sensor and a seven‐segment display in realistic scenarios. [ABSTRACT FROM AUTHOR]

Ribosomes composed of genome-encoded heterogeneous rRNAs are implicated in the rapid adaptation of bacterial cells to environmental changes. A previous study showed that ribosomes bearing the most heterogeneous rRNAs expressed from the rrnI operon (I-ribosomes) are implicated in the preferential translation of a subset of mRNAs, including hspA and tpiA, in Vibrio vulnificus CMCP6. In this study, we show that HspA nascent peptides were predominantly bound to I-ribosomes. Specifically, I-ribosomes were enriched more than two-fold in ribosomes that were pulled down by immunoprecipitation of HspA peptides compared with the proportion of I-ribosomes in crude ribosomes and ribosomes pulled down by immunoprecipitation of RNA polymerase subunit β peptides in the wild-type (WT) and rrnI-completed strains. Other methods that utilized the incorporation of an affinity tag in 23S rRNA or chimeric rRNA tethering 16S and 23S rRNAs, which generated specialized functional ribosomes in Escherichia coli, did not result in functional I-ribosomes in V. vulnificus CMCP6. This study provides direct evidence of the preferential translation of hspA mRNA by I-ribosomes. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal dichalcogenide (2D TMD) crystals are versatile platforms for realizing emergent optoelectronic devices. However, the ability to produce large-area 2D TMDs with spatial homogeneity and to accomplish broadband photodetection by tuning the operating wavelengths in photodetectors are two paramount prerequisites for practical applications of 2D TMD-based photodetectors. Here, we demonstrated all-solution-processed broadband photodetectors based on the wafer-scale perovskite quantum dots (PQDs)/MoS2 through light management via the monochromatization effect of the PQDs. The photodetectors exhibited broadband photodetection behavior that retained high photocurrents over a wide spectral range (254, 365, and 532 nm) by enhancing the photoresponse in the UV region through light management via the monochromatization effect of the PQDs. This intriguing strategy was proven with (i) electrical isolation realized by inserting an Al2O3 insulator between the PQDs and MoS2 and (ii) alteration of the PQD density. The rational nanohybrid-based photodetectors also exhibited superb air stability and exceptional bending durability. We developed all-solution-processed broadband photodetectors based on the wafer-scale perovskite quantum dots (PQDs)/MoS2 through light management via the monochromatization effect of the PQDs. The rational nanohybrid-based photodetectors exhibited broadband photodetection behavior that retained high photocurrents over a wide spectral range and also show superb air stability and exceptional bending durability. [ABSTRACT FROM AUTHOR]

High-performance, wearable, and self-powered mechanical sensors for human health monitoring, motion detection systems, and human–machine interfaces are attracting attention owing to the increased interest in green energy. Piezoelectric and triboelectric effects are being exploited to develop various types of self-powered mechanical sensors; however, unresolved issues such as complicated processes and limitations in material selection and practical applications remain. A type of effective self-powered mechanical sensor based on the hybrid triboelectric–flexoelectric effect of multilayered MoS2 hollow spheres is reported herein. This triboelectric–flexoelectric mechanical sensor (TFMS) exhibits superior sensing characteristics, including wide-range pressure detection and superior stability, owing to the remarkable hybrid triboelectric–flexoelectric effect of optimized MoS2 hollow spheres under stress. In addition, the operating mechanism of the fabricated TFMS is discussed based on the size and number of the multilayered MoS2 spheres using finite element method (FEM) simulations of the effective stress under pressure changes. Furthermore, the effective operation of the sensor in detecting various human physiological motions from the wrist pulse to walking/running is demonstrated. These results are expected to promote the development of advanced mechanical sensors for applications such as next-generation prostheses and human–machine interfaces. [ABSTRACT FROM AUTHOR]

Low‐temperature processes and simplification of lithographic techniques are key challenges for the fabrication of solution‐processed metal oxide‐based nanodevices. Recent breakthroughs in location‐specific synthetic methodologies involving inkjet printing and photon‐activation routes have enabled lithography‐free and bottom‐up fabrication of such devices. However, a revolutionary strategy to resolve room‐temperature direct fabrication of metal oxide‐based materials still remains elusive. Here, a pertinent route enabling wafer‐scale, location‐specific direct‐writing, termed "photon‐pen writing (PPW)," of functional metal oxide‐based devices is proposed. Using PPW, fabrication of elaborate patterns of metal oxides is demonstrated through location‐specific dechlorination and subsequent oxidation via thermal energy transfer of a focused infrared laser in ambient environment. By tailoring process parameters, precise manipulation of the chemical and structural features of the PPW‐produced metal‐oxide patterns are demonstrated. The versatility of the PPW process by realizing a highly sensitive, stable, uniform, and wafer‐scale nanosensor array for gas and light detection using PPW‐ZnO channel and PPW‐ITO electrodes is demonstrated, with 4.1% of response at 50 ppb NO2 and 2.93 ± 0.23 µA of photocurrent for 0.76 mW cm−2, 254 nm UV light. A new route toward wafer‐scale production of bespoke nanosensor arrays onto single chip for next‐generation nanoelectronics is introduced. [ABSTRACT FROM AUTHOR]

As a selection device for highly integrated crossbar‐type data storage, the chalcogenide‐based ovonic threshold switch (OTS) shows high selectivity, fast switching speed, and bi‐directional operation ability for stacking with versatile memory devices. These promising performance features of OTS are based on electronic resistance switching through the amorphous chalcogenide active layer. However, there is a need to improve the thermal stability of the chalcogenide material, which is essential for maintaining the amorphous structure, and the minimization of the operation voltage shift phenomenon, which is essential for achieving sufficient endurance performance. In this study, the active layer of Se‐doped (at 5%) GeTe (SGT) is investigated as a selection device with the potential for high thermal stability (<400 °C) and extreme endurance performance (>1012). The Se introduced into the GeTe (GT) layer compensates for the Te vacancy in the GT layer, making the SGT layer resistant to crystallization in high‐thermal‐budget circumstances. To achieve extremely high endurance performance, a device structural reconfiguration is proposed that minimizes the operation voltage shift by restricting the surge current in its initial resistance switching stage. The results of analyses of the materials and electrical characteristics of the OTS demonstrate its enhanced performance. [ABSTRACT FROM AUTHOR]

Selectivity for specific analytes and high‐temperature operation are key challenges for chemiresistive‐type gas sensors. Complementary hybrid materials, such as reduced graphene oxide (rGO) decorated with metal oxides enables realization of room‐temperature sensors with enhanced sensitivity. However, sensor training to identify target gases and accurate concentration measurement from gas mixtures still remain very challenging. This work proposes hybridization of rGO with CuCoOx binary metal oxide as a sensing material. Highly stable, room‐temperature NO2 sensors with a 50 ppb of detection limit is demonstrated using inkjet printing. A framework is then developed for machine‐intelligent recognition with good visibility to identify specific gases and predict concentration under an interfering atmosphere from a single sensor. Using ten unique parameters extracted from the sensor response, the machine learning‐based classifier provides a decision boundary with 98.1% accuracy, and is able to correctly predict previously unseen NO2 and humidity concentrations in an interfering environment. This approach enables implementation of an intelligent platform for printable, room‐temperature gas sensors in a mixed environment irrespective of ambient humidity. [ABSTRACT FROM AUTHOR]

We couple the spark plasma sintering (SPS) technique with the ball mill process to fabricate a new electro-chemo-mechanical functional carbon–metal oxide hybrid material. Graphene oxide (GO) or carbon nanotubes (CNT) carbon allotropes are mechanically mixed with gadolinium-doped ceria (CGO). SPS allows consolidating dense carbon–metal oxide hybrids with uniform morphology and high crystallinity. The carbon allotropes and SPS lead to highly reduced CGO. The metal oxide presents a chemically tuned grain boundary with highly oxygen defect concentration at the near-grain boundary region. The hybrid interface can hinder chemical oxidation at high-temperature depending on the carbon allotropy. As a result, the hybrid materials with CNT display high ionic conductivity and activation energy, reducing the space charge layer and charge distribution. This feature enhances the electromechanical properties at room temperature. We especially disclose electrostriction in the CNT-based hybrids superior to the pure CGO and follow a non-Newnham relation. Notably, integrating carbon materials with metal oxides using the SPS can generally be applied to synthesising a range of functional metal oxide composite. [ABSTRACT FROM AUTHOR]

Multi-element injectors have been used in liquid rocket engines to obtain high thrust, and the gas-centered swirl coaxial injector is a representative injection system because it provides high mixing performance. Investigations of the spray characteristics of injection systems have focused on the characteristics of single-element injectors, including the spray angle, breakup, and atomization mechanism of the liquid sheet formation. However, the spray characteristics of multi-element injectors need to be studied because of their usage in real rocket engine systems. In this paper, spray patterns and interacting spray under different injection conditions are analyzed using the backlight imaging technique, and the dominant flow fields are observed using the dynamic mode decomposition method. The spray angle in the case of the gaseous nitrogen with a high Reynolds number is calculated to be lower than the case with a low Reynolds number. From the averaged images, it is found that there are two dominant flow fields: one is located in the vicinity of the injector head and the other is in the interacting spray zone, which is related to a secondary breakup via an adjacent injector. As a result of the dynamic mode decomposition analysis, however, the spray zone near the injector is confirmed to be a more dominant flow field than the interacting spray zone. [ABSTRACT FROM AUTHOR]

A new type of coaxial hetero‐structured MoS2/SnO2 nanotube (MS‐NT) array is rationally designed for flexible visible light photodetector. Herein, a suitable solution for fabricating MS‐NT comprising SnO2 with controlled thickness and strain is proposed. The thickness of SnO2 deposited on MoS2 nanotubes are delicately manipulated by adjusting atomic layer deposition (ALD) cycles, which cause the internal tensile strain of the hybrid nanotubes. The photocurrent of the MS‐NT‐based photodetector exhibits high photoresponsivity values of 198.4 mA W‐1 and external quantum efficiency of 0.78%. In the analysis, a linear correlation between the excitation power and the photocurrent extracted from the MNT‐based devices is discerned. At the same time, a superlinearity of photocurrent in the MS‐NT arrays‐based device is found. Density functional theory calculations are adopted to unveil the strong correlation between the strain, bandgap, and photocurrent of the MS‐NT, which is a decisive factor for understanding the experimental evidences. The detailed mechanism for enhance photoresponsivity is further suggested for the strain‐tailored MS‐NT arrays‐based device. Such peculiar properties are expected to open a new chapter in the era of smart optical devices that require low driving voltage and high power efficiency. [ABSTRACT FROM AUTHOR]

2D transition metal carbides and nitrides, namely MXenes, are normally synthesized in acidic solutions and are delaminated in basic solutions. This results in versatile materials with unique physical/chemical properties suitable for various practical applications. However, solution‐based chemical treatments can affect the chemical structures of MXenes, which accelerates the oxidation reactions and degrades their intrinsic properties. Here, long‐term stable Ti3C2Tx dispersion in deep eutectic solvents (DESs) that resisted oxidation degradation for up to 28 weeks is demonstrated. As an anti‐oxidative dispersion medium, DESs helped prevent oxidation of Ti3C2Tx layers due to hydrogen bond accepting and donating molecules passivated surface of the Ti3C2Tx. In addition, DES molecules in bulk solution can also be hydrated in the presence of water, which stabilizes reactive oxygen by forming stable DES‐water cluster. Therefore, the use of DESs enhanced the delamination of the Ti3C2Tx nanosheets, while preventing oxidation of the nanosheets in solution and even in their dried state. As a result, thick and thin films of Ti3C2Tx fabricated using DESs exhibited stable sheet resistance in comparison with pristine‐Ti3C2Tx. In addition, Ti3C2Tx dispersed in DESs can be applied as electrodes for electrochemical capacitors, in which they showed higher chemical stability and better performance than pristine Ti3C2Tx. [ABSTRACT FROM AUTHOR]

Even though molybdenum disulfide (MoS2) possesses superb features, its practical application in optoelectronics is hindered by the lack of a reliable synthetic route for producing large‐scale two‐dimensional (2D) MoS2 with spatial homogeneity and a pertinent patterning technique that can be used to realize 2D MoS2‐based photodetector arrays. To resolve these issues, the effectiveness of an unprecedented combination of a solution‐based synthetic route with resist‐ and etching‐free patterning of 2D MoS2 mediated by pre‐defined photosensitive polyimide (PSPI) for realizing 2D MoS2‐based photodetector arrays is demonstrated. A solution‐based large‐area compatible approach is adopted for the synthesis of MoS2. Comprehensive structural and chemical analysis of the MoS2 synthesized by altering the concentration of ammonium tetrathiomolybdate is performed to determine the optimum conditions for enhancing the photoelectrical responses of MoS2‐based photodetectors. It is ascertained that the photocurrent of MoS2‐based photodetectors fabricated by PSPI‐assisted patterning is unequivocally greater than that of photodetectors produced via the conventional photolithography process owing to the absence of photoresist residues associated with impeding photon absorption and providing scattering centers of photogenerated carriers. [ABSTRACT FROM AUTHOR]

Although energy‐storage devices based on Li ions are considered as the most prominent candidates for immediate application in the near future, concerns with regard to their stability, safety, and environmental impact still remain. As a solution, the development of all‐solid‐state energy‐storage devices with enhanced stability is proposed. A new eco‐friendly polymer electrolyte has been synthesized by incorporating lithium trifluoromethanesulfonate into chemically modified methyl cellulose (LiTFS–LiSMC). The transparent and flexible electrolyte exhibits a good conductivity of near 1 mS cm−1. An all‐solid‐state supercapacitor fabricated from 20 wt % LiTFS–LiSMC shows comparable specific capacitances to a standard liquid‐electrolyte supercapacitor and an excellent stability even after 20 000 charge–discharge cycles. The electrolyte is also compatible with patterned carbon, which enables the simple fabrication of micro‐supercapacitors. In addition, the LiTFS–LiSMC electrolyte can be recycled and reused more than 20 times with negligible change in its performance. Thus, it is a promising material for sustainable energy‐storage devices. [ABSTRACT FROM AUTHOR]

GLO:1VT/16aug21:embj2021108671-toc-0001.jpg PHOTO (COLOR): . gl Previously, we provided experimental evidence demonstrating the discriminative miRNA targeting of a mutated site within the coding sequence of a variant allele (c.402C>G; p.C134W) of the tumor-suppressor gene I FOXL2 i that results in lower expression levels of the variant I FOXL2 i mRNA (Shin I et al i , 2020). Our I in vivo i genome-editing results clearly demonstrate that miR-1236 is an endogenous functional miRNA that specifically downregulates variant I FOXL2 i mRNA (Shin I et al i , 2020). We disagree with the claims of Veitia I et al i based on the simple interpretation of the height of the electropherograms obtained from the Sanger sequencing analysis (fig 1of Veitia I et al i ). [Extracted from the article]

Real-time detection of gaseous pollutants is of great interest to both environmental monitoring and chemical related health hazard control. Here, we report the drastic effect of a controllable heterointerface between methyl cellulose (MC) buffer layers and pentacene on the performance of organic field-effect transistor (OFET)-based gas sensors. Compared with pristine pentacene films, fabricated pentacene films with underlying MC layers, which alter the growth of pentacene and introduce structural trapping effects, improve the gas responsivity with a detection limit for NO2 as low as 1 ppm. The underlying MC multiplies the number of chemically active grain boundaries of pentacene according to morphological evaluation and impedance spectroscopy. The sensitivity of the sensors is further amplified by dipole aligning of hydroxyl-terminated MC. Our findings suggest that cellulosic materials, which simultaneously enable sophisticated control over the growth of organic thin films and electrostatic interaction of gas molecules, are considered to be excellent candidates as the buffer layer for low-cost and high-performance OFET-based gas sensors. [ABSTRACT FROM AUTHOR]

Abstract: Accidents related to spilling of chemicals and chemical wastes are never ceasing, especially as our reliance on chemical products increases continuously. For the sake of workers' safety and maintenance of our environment, it is important to not only reduce the frequency of such accidents but also minimize the damage from each accident through proper spill control methods. Our focus here is to address the issues regarding rapid evaporation of the hazardous volatile organic liquids spills and propose a potential sorbent material, cellulose acetate, which can significantly reduce the rate of evaporation of highly volatile chemicals such as acetone, acrolein, and propylene oxide. Compared to conventional chemical sorbents such as activated carbon, expanded vermiculite, and cellulose, cellulose acetate not only exhibits higher vapor retention abilities, but also demonstrates comparable sorption efficiencies for sorption of acetone, acrolein, and propylene oxide. Cellulose acetate is also an environmentally friendly and economical material that is safe to use even for sorption of highly flammable chemicals, thus, its potential as a new class of commercial chemical sorbent is very promising.Graphical abstract: [ABSTRACT FROM AUTHOR]

Energy technologies of the near future will heavily rely on electrochemical systems; hence, the importance of research on electrocatalytically active materials can never be emphasized enough. For hydrogen evolution, precious metal catalysts (e.g. platinum) are the acclaimed performers, but recently, two-dimensional transition metal dichalcogenides (TMDs) have been receiving immense interest due to their noteworthy catalytic activity and earth-abundance. In particular, molybdenum disulfide (MoS2) in its metallic 1T-phase is known to exhibit outstanding performance; thus, utilizing 1T-MoS2 is of high interest. Here, MoS2 is synthesized via a microwave-assisted solvothermal method (MoS2-MW). Remarkably, the MoS2-MW film revealed randomly oriented flake-like grains; thus, highly active edge-sites are vastly exposed to the surface. Moreover, investigations of the film exposed the highly stable structural hybrid of the 1T- and 2H-phases, which remarkably exhibits electrocatalytic attributes of pure 1T-MoS2 with superb catalytic activity. The method allows synthesis of MoS2-MW over morphologically complex conducting substrates to increase both the number and catalytic activity of active sites for hydrogen evolution. [ABSTRACT FROM AUTHOR]

Abstract: A step‐by‐step strategy is reported for improving capacitance of supercapacitor electrodes by synthesizing nitrogen‐doped 2D Ti2CTx induced by polymeric carbon nitride (p‐C3N4), which simultaneously acts as a nitrogen source and intercalant. The NH2CN (cyanamide) can form p‐C3N4 on the surface of Ti2CTx nanosheets by a condensation reaction at 500–700 °C. The p‐C3N4 and Ti2CTx complexes are then heat‐treated to obtain nitrogen‐doped Ti2CTx nanosheets. The triazine‐based p‐C3N4 decomposes above 700 °C; thus, the nitrogen species can be surely doped into the internal carbon layer and/or defect site of Ti2CTx nanosheets at 900 °C. The extended interlayer distance and c‐lattice parameters (c‐LPs of 28.66 Å) of Ti2CTx prove that the p‐C3N4 grown between layers delaminate the nanosheets of Ti2CTx during the doping process. Moreover, 15.48% nitrogen doping in Ti2CTx improves the electrochemical performance and energy storage ability. Due to the synergetic effect of delaminated structures and heteroatom compositions, N‐doped Ti2CTx shows excellent characteristics as an electrochemical capacitor electrode, such as perfectly rectangular cyclic voltammetry results (CVs, R2 = 0.9999), high capacitance (327 F g−1 at 1 A g−1, increased by ≈140% over pristine‐Ti2CTx), and stable long cyclic performance (96.2% capacitance retention after 5000 cycles) at high current density (5 A g−1). [ABSTRACT FROM AUTHOR]

Three-layered ZnO-CuO-SnO2 hybrid nanostructures n-p-n hetero-junctions were synthesized for the first time by 3-step chemical vapor deposition on SiO/Si substrates. Starting materials made of Cu, Zn and Sn powder mixed with carbon charcoal were heated at various temperatures and pressures under atmosphere of O2 and Ar. The prepared samples were investigated by field emission scanning electron microscope (FESEM), X-rays photoemission spectroscopy (XPS), and I-V characteristic curves. The results reveals the formation of CuO hollow microspheres with branching lines, ZnO nanowires, and SnO2 nanorods in which establish the three layers of the hetero-junctions. I-V characteristics exhibit rectifying behavior of hetero-layered semiconductors. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials, including graphene and transition metal dichalcogenides (TMDs) such as molybdenum disulfide (MoS2) and tungsten diselenide (WSe2), have recently attracted attention due to their applicability as building blocks for fabricating advanced functional materials. In this study, a novel method for synthesizing hybrid materials based on flexible graphene fibers and 2D TMD nanosheets was demonstrated by using chemical vapor deposition. An organic promoter layer was employed for the large-scale growth of the TMD sheet, and the subsequent metalation process of the promoter layer was carried out to modulate the electrical properties of the TMD layers on graphene fibers. As a proof of concept, fiber-type photodetectors based on graphene fibers and 2D TMD nanosheets were successfully fabricated and investigated; they showed a high photoresponsivity of 5.73 A W−1. Our novel approach is a promising effective method for the fabrication of fiber-type photodetectors with a new structure for application in TMD-based transparent and flexible optoelectronic devices. [ABSTRACT FROM AUTHOR]

RraA is a protein inhibitor of RNase E, which degrades and processes numerous RNAs in Escherichia coli. Streptomyces coelicolor also contains homologs of RNase E and RraA, RNase ES and RraAS1/RraAS2, respectively. Here, we report that, unlike other RraA homologs, RraAS1 directly interacts with the catalytic domain of RNase ES to exert its inhibitory effect. We further show that rraAS1 gene deletion in S. coelicolor results in a higher growth rate and increased production of actinorhodin and undecylprodigiosin, compared with the wild-type strain, suggesting that RraAS1-mediated regulation of RNase ES activity contributes to modulating the cellular physiology of S. coelicolor. [ABSTRACT FROM AUTHOR]