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With the continuous development of society, the energy demand is also increasing, and the consumption of fossil fuels is becoming more and more serious. Dielectric capacitors are widely used in electronic devices due to their advantages of fast charging and discharging speed and high power density. In this work, 2D-Na 0.5 Bi 0.5 TiO 3 (2D-NBT) filler and polyimide (PI) polymer matrix were compounded to prepare 2D-NBT/PI composites, and the energy storage performance of the composites was improved by surface modification of the filler and the design of 'sandwich' structure. The prepared samples were analyzed by XRD, SEM and dielectric properties. For 2D-NBT/PI single-layer composites, when the volume fraction of NBT powder is 0.25 vol.%, the energy storage density of the composites reaches 11.11 J/cm3 under the electric field of 400 kV/mm. For the 'sandwich' structure 2D-NBT/PI composites, when the system of 2D-NBT/PI composites is 0.25-0-0.25, the energy storage density of the composites reaches 12.44 J/cm3 under the electric field of 440 kV/mm. [ABSTRACT FROM AUTHOR]

Amid the increasing focus on sustainable energy, hydrogen generation through photocatalysis has garnered substantial attention in recent years. Given their distinctive electronic, optical, and structural properties, two-dimensional perovskite nanosheets have surfaced as promising contenders as photocatalysts. Here we present a systematic exploration of Ruddlesden-Popper phase Ca n-1 Mn n-3 Nb 3 O 3n+1 2− (n = 4,5,6) perovskite (CMNO) nanosheets with distinct layers (n = 4, 5, and 6), synthesized via exfoliation approach, for enhanced physicochemical properties and catalytic performances. Rigorous characterizations supported by the Tauc plot and Mott-Schottky analysis reveal the crystal structures, varied bandgaps, and an n-type semiconductor behavior from the CMNO nanosheets. In a novel approach to enhance its photo-absorption, Chlorella vulgaris microalgae, strategically layered onto the CMNO nanosheets, consequently exhibit significant improvements in the onset potential and current density, especially for the CMNO (n = 6) nanosheet. This research lays a foundation for understanding the tailored composition and layer-dependent properties of CMNO nanosheets, propelling their potential application in efficient hydrogen generation through photoelectrochemical water splitting for sustainable energy technologies. • Ruddlesden-Popper phase of Ca n-1 Mn n-3 Nb 3 O 3n+1 was prepared using soft chemistry method to obtain n = 4, 5, 6 layers. • Density of States shows that n = 6 layers exhibit more bonding states than n = 4 and 5, thus contributing to photocatalysis. • Coupled with PEDOT:PSS, CMNO is layered on ITO to form a p-n junction based photoelectrode for hydrogen generation. • Chlorella vulgaris was layered on the photoelectrode to improve visible light absorption and charge-carrier separation. • The introduction of Chv on the photoelectrode significantly improves the ABPE% up to 0.15% against the control group 0.05%. [ABSTRACT FROM AUTHOR]

Two-dimensional materials have excellent electronic and optical properties, suggesting absolute advantages in nanodevices. In this work, a new two-dimensional material with a puckered structure, a C2B6 monolayer, is proposed. The material presents dynamic and thermal stability calculated by first-principle simulations. Interestingly, the C2B6 monolayer possesses semiconductor behavior with an ultra-narrow bandgap of approximately 0.671 eV by HSE06 functional. Meanwhile, the hole in the C2B6 monolayer shows ultrahigh mobility at approximately 6,342 cm2⋅V−1⋅s−1 in decent transport directions, which is larger than traditional transition metal dichalcogenides materials. More importantly, the pronounced anisotropy of mobility of the electrons and holes can separate the photogenerated charges, suggesting the applications for photocatalytic, photovoltaic and optical and cold chain electronic devices. Then, the novel properties of the light absorption characteristic are obtained, and the anisotropic photocurrent implies the C2B6 monolayer can be used as a potential photoelectric device. Our results provide theoretical guidance for the design and application of two-dimensional materials. [ABSTRACT FROM AUTHOR]

Metal sulfide-based composites have become increasingly common as materials used for electrodes in supercapacitors because of their excellent conductivity, electrochemical activity, and redox capacity. This study synthesized a composite of NiFeS@MoS2@rGO nanostructure using a simple hydrothermal approach. The synthesized nanocomposite consisted of the composite of nickel sulfide and iron sulfide doped with MoS2@rGO. A three-electrode cell is employed to investigate the electrochemical properties of the NiFeS@MoS2@rGO electrode. The results demonstrated an optimal specific capacitance of 3188 F/g at 1.4 A/g in a 1 M KOH electrolyte. Furthermore, a supercapattery is designed utilizing NiFeS@MoS2@rGO//AC as the positive electrode and activated carbon (AC) as the negative electrode materials. The resulting supercapattery is designed at a cell voltage of 1.6 V, achieving a specific capacity value of 189 C/g at 1.4 A/g. It also demonstrated an excellent energy density of 55 Wh/kg with an enhanced power density of 3800 W/kg. Furthermore, the hybrid device demonstrated remarkable stability with a cycling stability of 95% over 30,000 charge–discharge cycles at a current density of 1.4 A/g. The supercapattery, which has excellent energy storage capabilities, is used as a power source for operating different portable electronic devices. [ABSTRACT FROM AUTHOR]

In the present work the atomic, electronic and optical properties of two-dimensional graphene, borophene, and boron carbide heterojunction bilayer systems (Graphene–BC3, Graphene–Borophene and Graphene–B4C3) as well as their constituent monolayers are investigated on the basis of first-principles calculations using the HSE06 hybrid functional. Our calculations show that while borophene is metallic, both monolayer BC3 and B4C3 are indirect semiconductors, with band-gaps of 1.822 eV and 2.381 eV as obtained using HSE06. The Graphene–BC3 and Graphene–B4C3 bilayer heterojunction systems maintain the Dirac point-like character of graphene at the K-point with the opening of a very small gap (20–50 meV) and are essentially semi-metals, while Graphene–Borophene is metallic. All bilayer heterostructure systems possess absorbance in the visible region where the resonance frequency and resonance absorption peak intensity vary between structures. Remarkably, all heterojunctions support plasmons within the range 16.5–18.5 eV, while Graphene–B4C3 and Graphene–Borophene exhibit a π -type plasmon within the region 4–6 eV, with the latter possessing an additional plasmon at the lower energy of 1.5–3 eV. The dielectric tensor for Graphene–B4C3 exhibits complex off-diagonal elements due to the lower P3 space group symmetry indicating it has anisotropic dielectric properties and could exhibit optically active (chiral) effects. Our study shows that the two-dimensional heterostructures have desirable optical properties broadening the potential applications of the constituent monolayers. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have been widely studied due to their versatile applications and easily tunable structures. However, heteroatom‐metal coordination dominates the MOFs community, and the rational synthesis of carbon–metal coordination‐based MOFs remains a significant challenge. Herein, two‐dimensional (2D) MOFs based on silver–carbon linkages are synthesized through the coordination between silver(I) salt and isocyanide‐based monomers at ambient condition. The as‐synthesized 2D MOFs possess well‐defined crystalline structures and a staggered AB stacking mode. Most interestingly, these 2D MOFs, without π–π stacking between layers, exhibit narrow band gaps down to 1.42 eV. As electrochemical catalysts for converting CO2 to CO, such 2D MOFs demonstrate Faradaic efficiency over 92 %. Surprisingly, the CO2 reduction catalyzed by these MOFs indicates favorable adsorption of CO2 and *COOH on the active carbon sites of the isocyanide groups rather than on silver sites. This is attributed to the critical σ donor role of isocyanides and the corresponding ligand‐to‐metal charge–transfer effect. This work not only paves the way toward a new family of MOFs based on metal–isocyanide coordination but also offers a rare platform for understanding the electrocatalysis processes on strongly polarized carbon species. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the existing evidence regarding the comparison between 2 and 3D systems in Total Laparoscopic Hysterectomy (TLH) in terms of surgical outcomes. Methods: A systematic review of electronic databases, including PubMed/MEDLINE and Web of Science, was conducted to identify relevant studies comparing 2D and 3D systems in TLH. The search employed a combination of Medical Subject Headings (MeSH) terms and keywords related to the topic. Studies meeting predefined criteria were included, while case reports and studies not directly comparing 2D and 3D systems were excluded. Two independent reviewers evaluated study eligibility and performed quality assessment. The quantitative synthesis was conducted using meta-analysis techniques. Results: A statistically significant longer operation time in the 2D group compared to the 3D group (7 studies, mean difference [MD]: 13.67, 95% confidence interval [CI] 9.35–18.00, I2 = 16%). However, no statistically significant differences were found between the groups in terms of vaginal cuff closure time (2 studies, MD: 3.22, CI − 6.58–13.02, I2 = 96%), complication rate (7 studies, odds ratio [OD]: 1.74, CI 0.70–4.30, I2 = 0%), blood loss (3 studies, MD: 2.92, CI − 15.44–21.28, I2 = 0%), and Hb drop (3 studies, MD: 0.17, CI − 0.08–0.42, I2 = 1%). Conclusion: Our results revealed a significant difference favoring 3D systems in operation time, while clinical outcomes between the two systems were found to be comparable in TLH. However, further research, particularly prospective studies with larger cohorts and longer-term follow-up, along with economic analyses, is needed to provide clinicians and healthcare decision-makers with essential guidance for practice and resource allocation. [ABSTRACT FROM AUTHOR]

With the growing demand for high‐performance smart windows, the discover of a class of thermochromic materials with reversible cycling and rapid response characteristics has become urgent. In this work, we have uncovered a two‐dimensional (2D) Ruddlesden‐Popper (RP) phase halide perovskite, (PMA)2MAPb2I7−xClx, where PMA=C6H5CH2NH3 and MA=CH3NH3, exhibiting exceptional reversible thermochromic properties. The 2D RP phase perovskite thin film features a low transition temperature (Tc=30 °C from the hydrated state to the hot state, along with a fast transition time of 40 s. Furthermore, the addition of 0.5 times excess MAI significantly enhances the visible light transmittance of the hydrated state. Characteristic hydration peaks in X‐ray diffraction patterns and O−H bond absorption peaks Fourier‐transform infrared spectra are observed in the thin film in its hydrated state, which disappear in the hot state, validating its reversible thermochromic properties. Additionally, a solar cell based on the thermochromic 2D RP phase thin film achieves a power conversion efficiency of 2.31 %, offering a promising solution for advanced smart window technologies. [ABSTRACT FROM AUTHOR]

Disordered hyperuniformity (DHU) is a recently discovered novel state of amorphous systems characterized by strongly suppressed density fluctuations at large length scales as in crystalline materials, which offers great potential for achieving unusual mechanical, electronic, and photonic properties. However, despite the fundamental and technological importance of thermal transport in amorphous solids, the effect of DHU remains largely unexplored. Here, we theoretically study thermal transport in a class of two-dimensional DHU materials—monolayer amorphous carbon (MAC). Beginning with a perfect graphene lattice, we continuously apply Stone-Wales transformations to generate a series of MAC models with varied degrees of disorder and defects, which are quantified through comprehensive structural analysis including the so-called hyperuniformity index (H), where a smaller H indicates a higher degree of hyperuniformity. Subsequently, we conduct molecular dynamics simulations to obtain the thermal conductivity (κ). A significant correlation between the thermal transport behavior and degree of hyperuniformity is observed, with the room-temperature κ decreasing from 26.3 to 5.3 W m−1 K−1 while H is tuned from 0.0004 to 0.024. Remarkably, two distinct transport regimes are identified, including a nearly-DHU regime at small H (< 0.005) where κ drops sharply and a non-DHU region at larger H where κ becomes relatively flat. Mode-resolved analysis reveals longer lifetime and higher participation ratio for the heat carriers in nearly-DHU MAC, implying that the hidden long-range correlations could support extended modes that enhance transport. Our work highlights the impact of DHU on the thermal properties of amorphous materials and represents a conceptual advancement that is worthy of future exploration. [ABSTRACT FROM AUTHOR]

Using a first-principles approach, this study delves into the effects of strain and electrostatic doping on the electronic and magnetic properties of the GaN/VTe2 van der Waals (vdW) heterostructure. The results reveal that when the GaN/VTe2 vdW heterostructure is doped with 0.1 h /0.2 h of electrostatic charge, its magnetization direction undergoes a remarkable reversal, shifting from out-of-plane orientation to in-plane direction. Therefore, we conduct a thorough investigation into the influence of electron orbitals on magnetic anisotropy energy. In addition, as the strain changes from −1% to 1%, the 100% spin polarization region of the GaN/VTe2 vdW heterostructure becomes smaller. It is worth noting that at a doping concentration of 0.1 h, the GaN/VTe2 vdW heterostructure has a Curie temperature of 30 K above room temperature. This comprehensive study provides valuable insights and provides a reference for analyzing the electronic and magnetic properties of low-dimensional systems. [ABSTRACT FROM AUTHOR]

Purpose: Most shoulder pathologies are associated with altered scapular kinematics which is mentioned as scapular dyskinesis. Scapular mobility, especially in upward rotation, measurement is essential for diagnosis and treatment. Easy-to-use, clinically applicable 2-dimensional (2-D) measurements would show excellent intra-tester reliability. To quantify intra-tester reliability for measuring scapular upward rotation in individuals with scapular dyskinesias, the landmark palpation with a video annotation tool was used. Methods: Ten participants with scapular dyskinesis were recruited. Scapular upward rotation was measured at rest, 30∘, 60∘, 90∘, and 120∘ of humeral elevation in the coronal plane both raising and lowering phases. Two trials were conducted for each arm position randomly, and an assessor took the pictures throughout. The video annotation tool (2-D Kinovia program) was used for measuring scapular upward rotation angles between days. The intra-tester reliability of scapular upward rotation was calculated. Results: This measurement technique demonstrated excellent intra-tester reliability (ICC3,1 = 0.98), range 0.96–0.99, and standard error of measurement was less than 1∘. Conclusions: The findings demonstrated that using this technique to measure scapular upward rotation was reliable in subjects with scapular dyskinesis. [ABSTRACT FROM AUTHOR]

Two‐dimensional conductive MOF thin films have attracted attention due to their rich pore structure and unique electrical properties, and their applications in many fields, including batteries, sensing, supercapacitors, electrocatalysis, etc. This paper discusses several preparation methods for 2D conductive MOF thin films. And the applications of 2D conductive MOF thin films are summarized. In addition, the current challenges in the preparation of 2D conductive MOF thin films and the great potential in practical applications are discussed. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) can effectively remove methylene blue (MB) from wastewater due to their abundant adsorption sites and multi‐level pores. In this paper, a copper‐based MOF: {[Cu ⋅ (L) ⋅ (H2O)] ⋅ (DMF)}n (1) (H2L=2‐hydroxyterephthalic acid; DMF=N,N‐dimethylformamide), was synthesized by hydrothermal synthesis method. X‐ray single crystal diffraction showed that a two‐dimensional structure was formed by the carboxyl group of L2− in 1 took μ2‐η1 : η1 bridged two adjacent Cu(II). In this two‐dimensional structure, the coordinated water molecules and hydroxyl group on L2− were distributed on the surface of 1. Thus, it had abundant adsorption sites. The transmission electron microscopy (TEM) of copper‐based MOF nano adsorbent showed that the particle diameter of the nano adsorbent prepared by a cell fragmentation apparatus was about 50 nm. The performance of the copper‐based MOF nano adsorbent in adsorbing MB indicated that the optimal adsorbent dosage was 0.20 g/L and the solution pH was 6. Under the optimal experimental conditions, its maximum adsorption capacity for MB was 143.3 mg/g, which was superior to most MOFs adsorbents. The adsorption thermodynamic analysis showed that the copper‐based MOF nano adsorbent at 25–45 °C was an exothermic (ΔH<0), and spontaneous (ΔG<0) process. [ABSTRACT FROM AUTHOR]

Hydrogen is seen as an ideal alternative fuel to fossil fuels because it is green and sustainable. With the increasing energy crisis, developing efficient catalysts for hydrogen production to alleviate resource depletion is urgent. As a new member in the family of two-dimensional (2D) transition metal dichalcogenides (TMDs), 2D rhenium disulfide have attracted much attention based on their unique properties. In this paper, based on the unusual structural features and excellent properties of 2D rhenium disulfide, we cite their applications in the field of electrocatalytic water splitting and provide an in-depth understanding of the reaction mechanism. Furthermore, we enumerate the various synthetic methods of 2D rhenium disulfide and summarize the different strategies and current research progress in modulating their catalytic performances. Finally, we discuss the challenges faced by 2D rhenium disulfide in terms of synthetic methods and modulation strategies, and provide insights into their possible future development directions, hoping to provide valuable guidance for the design and preparation of high-performance rhenium-based electrocatalysts in the future. [Display omitted] • The unique structure and properties of 2D rhenium disulfide are presented. • Various synthetic methods of 2D rhenium disulfide are summarized. • Strategies for improving the catalytic performances are discussed. [ABSTRACT FROM AUTHOR]

Bacteria affect food quality in developing countries by spreading through contaminated soils and water. Antibiotics are used indiscriminately to eliminate Gram-positive and Gram-negative bacteria, with varying degrees of success. The use of nanomaterials with bactericidal properties can minimize the overuse of antibiotics. In this study, a two-dimensional p-type ZnO powder was successfully synthesized and its bactericidal properties were demonstrated. The XRD and Raman spectroscopy results indicated the presence of wurtzite-phase ZnO with Oi as the predominant native defect, resulting in p-type conductivity. SEM analysis confirmed the two-dimensional morphology, and optoelectronic characterization revealed a bandgap of 3.17 eV. Despite this high bandgap value, a plasmonic effect was generated on the surface of two-dimensional ZnO, which enhanced its bactericidal properties when the powders were in contact with bacteria. From an initial colony level of 5.5 × 105 CFU/mL, a significant decrease in the number of Gram-positive bacteria to 1.15 × 105 CFU/mL was observed, whereas the number of Gram-negative bacteria slightly increased to 1.45 × 106 CFU/mL. The observed inhibition rates were higher than those achieved with the broad-spectrum antibiotic, as validated in this study. The use of two-dimensional ZnO may provide a sustainable solution for the eradication of waterborne pathogens using visible light alone. [ABSTRACT FROM AUTHOR]

In this article, a numerical scheme for solving two‐dimensional (2D) time‐dependent incompressible Navier–Stokes equations is presented. The artificial compressibility technique is used to incorporate a time derivative of pressure term to the continuity equation. It is employed for pressure–velocity coupling. The scheme consists of backward difference approximation for time derivatives and central difference approximation for spatial derivatives, implemented on a collocated grid. The discretization of the differential equations yields a system of algebraic equations with a block coefficient matrix. To solve this system efficiently, matrix inversion with sparse matrix computation is employed. The proposed numerical scheme is applied to solve three flow problems (lid‐driven cavity flow, rectangular channel flow, and Taylor–Green vortex problem) to validate the accuracy and applicability of the scheme. The results affirm the scheme's capability to provide precise approximations for solutions to the Navier–Stokes equations. With slight modifications, the scheme can be applied to solve various flow problems with high accuracy, less memory usage, and reduced computational time. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have drawn extensive attention due to their exceptional characteristics and potential uses in electronics and energy storage. This investigation employs simulations using molecular dynamics to examine the mechanical and thermal transport attributes of the 2D silicene–germanene (Si-Ge) lateral heterostructure. The pre-existing cracks of the Si-Ge lateral heterostructure are addressed with external strain. Then, the effect of vacancy defects and temperature on the mechanical attributes is also investigated. By manipulating temperature and incorporating vacancy defects and pre-fabricated cracks, the mechanical behaviors of the Si-Ge heterostructure can be significantly modulated. In order to investigate the heat transport performance of the Si-Ge lateral heterostructure, a non-equilibrium molecular dynamics approach is employed. The efficient phonon average free path is obtained as 136.09 nm and 194.34 nm, respectively, in the Si-Ge heterostructure with a zigzag and armchair interface. Our results present the design and application of thermal management devices based on the Si-Ge lateral heterostructure. [ABSTRACT FROM AUTHOR]

An effective formula for the shape-sensitivity analysis of electromagnetic scattering is presented in this paper. First, based on the boundary element method, a new electromagnetic scattering formula is derived by combining the traditional electromagnetic scattering formula with the non-uniform rational B-spline (NURBS) curve, and the geometric model is represented by NURBS, which ensures the geometric accuracy, avoids the heavy grid division in the optimization process, and realizes the fast calculation of high-fidelity numerical solutions. Second, by deducing the sensitivity variables, the electromagnetic scattering equation of shape optimization is obtained, which can provide reliable data references for shape optimization. Finally, the effectiveness and accuracy of the algorithm are demonstrated by an example, and the sensitivity data of some examples are given. [ABSTRACT FROM AUTHOR]

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The inverse finite element method (iFEM) is a powerful tool for shape sensing and structural health monitoring and has several advantages with respect to some other existing approaches. In this study, a two-dimensional four-node quadrilateral inverse finite element formulation is presented. The element is suitable for thin structures under in-plane loading conditions. To validate the accuracy and demonstrate the capability of the inverse element, four different numerical cases are considered for different loading and boundary conditions. iFEM analysis results are compared with regular finite element analysis results as the reference solution, and very good agreement is observed between the two solutions demonstrating the capability of iFEM approach. [ABSTRACT FROM AUTHOR]

Understanding the relationship between vehicle speed and the risk of sustaining a life-threatening injury has garnered continual attention. This study seeks to gain deep insight into the relationship between two-vehicle speeds and the risk of serious injury at intersections. The 2016–2018 crash data that occurred at intersections from the US Crash Report Sampling System (CRSS) were examined. We present a more general framework that allows the crash risk to be simultaneously linked to a universal two-dimensional variable of two-vehicle speeds, instead of the one-dimensional variable of impact speed calculated according to crash types in the existing literature. The results indicate that the risk of serious injury for head-on crashes in the medium-speed zone is mainly influenced by the faster vehicle although having little relation to the slower vehicle. More importantly, we find that the marginal relationship between the two-vehicle speeds and the crash risk is non-monotonic for angle and rear crashes. Finally, appropriate measures are suggested to reduce the crash risk at intersections, including alerting the driver not to cross intersections at exceedingly low speed, assisting the driver in making an emergency response at a medium speed, and warning the driver not to operate at a very high speed. [ABSTRACT FROM AUTHOR]

The bandgap modulation and electronic properties modulation of two-dimensional HfSi2N4 monolayer induced by strain, electric field and atomic adsorption are studied by first principles. The HfSi2N4 monolayer was found to be dynamically, thermally, and mechanically stable at equilibrium, and it is a direct semiconductor with a bandgap of 1.87 eV. The bandgap of the HfSi2N4 monolayer can be precisely modulated by strain. Under the action of strain, HfSi2N4 monolayer not only transforms from direct semiconductor to indirect semiconductor, but also improves the absorption of visible light. An external electric field in the 0–0.5 eV/Å range can also modulate the bandgap of HfSi2N4 monolayer from 1.87 eV to 0 eV, and most importantly, at an external electric field of 0.5 eV/Å, HfSi2N4 monolayer shows the characteristics of spin gapless semiconductor. The calculated adsorption energy shows that the structures of H, O and F atoms adsorbed by HfSi2N4 monolayer can all exist stably. The bandgap of the configuration after adsorption of O and F atoms is significantly reduced compared with that of HfSi2N4 monolayer. Furthermore, the HfSi2N4 monolayer after adsorption of H and F atoms is transformed into a magnetic semiconductor. Method: All calculations were performed using Vienna ab initial simulation package, The electronic structure, mechanical properties, electronic properties and other properties were carried out using generalized gradient approximation (GGA-PBE), supplemented by HSE06 and GGA + U. The total-energy and force convergence are less than 10–6 eV and 0.001 eV/Å, respectively. The vacuum on the z-axis is selected 20 Å. The vdW interactions were corrected using the Grimme scheme (DFT-D3). [ABSTRACT FROM AUTHOR]

Outstanding charge transport in molecular crystals is of great importance in modern electronics and optoelectronics. The widely adopted strategies to enhance charge transport, such as restraining intermolecular vibration, are mostly limited to organic molecules, which are nearly inoperative in 2D inorganic molecular crystals currently. In this contribution, charge transport in 2D inorganic molecular crystals is improved by integrating charge‐delocalized Se8 rings as building blocks, where the delocalized electrons on Se8 rings lift the intermolecular orbitals overlap, offering efficient charge transfer channels. Besides, α‐Se flakes composed of charge‐delocalized Se8 rings possess small exciton binding energy. Benefitting from these, α‐Se flake exhibits excellent photodetection performance with an ultrafast response rate (~5 μs) and a high detectivity of 1.08 × 1011 Jones. These findings contribute to a deeper understanding of the charge transport of 2D inorganic molecular crystals composed of electron‐delocalized inorganic molecules and pave the way for their potential application in optoelectronics. [ABSTRACT FROM AUTHOR]

Two-dimensional materials have excellent electronic and optical properties, suggesting absolute advantages in nanodevices. In this work, a new two-dimensional material with a puckered structure, a C2B6 monolayer, is proposed. The material presents dynamic and thermal stability calculated by first-principle simulations. Interestingly, the C2B6 monolayer possesses semiconductor behavior with an ultra-narrow bandgap of approximately 0.671 eV by HSE06 functional. Meanwhile, the hole in the C2B6 monolayer shows ultrahigh mobility at approximately 6,342 cm2⋅V−1⋅s−1 in decent transport directions, which is larger than traditional transition metal dichalcogenides materials. More importantly, the pronounced anisotropy of mobility of the electrons and holes can separate the photogenerated charges, suggesting the applications for photocatalytic, photovoltaic and optical and cold chain electronic devices. Then, the novel properties of the light absorption characteristic are obtained, and the anisotropic photocurrent implies the C2B6 monolayer can be used as a potential photoelectric device. Our results provide theoretical guidance for the design and application of two-dimensional materials.

ObjectiveThe objective of this study was to develop a sonographic technique using two-dimensional (2D) markers for detecting isolated fetal cleft palate (no cleft lip) and to evaluate the ability of 2D and three-dimensional (3D) sonography to image the normal and abnormal palate. Methods Seventy-three fetuses with a high risk of cleft palate at 12-39 weeks of gestation were referred for specialist ultrasound. A detailed evaluation of the palate was performed through 2D ultrasound, which revealed the appearance of the palatine line in the sagittal plane; the palate and alveolar ridge in the coronal plane of the fetal face; the horizontal plate of the palatine bone in the axial maxillary plane; and the soft palate in the transverse plane of the cavum pharyngis. Subsequently, 3D ultrasound imaging of the palate was performed in all fetuses. Antenatal diagnoses were compared with postnatal findings or autopsy findings. Results Visualization of 2D markers was accomplished in all fetuses, and 3D assessment was achieved in 97% of fetuses. Cleft palate was suspected in 16 cases (21.9%), among which 14 were suspected on the basis of both 2D and 3D evaluation, and two were suspected only on the basis of 3D evaluation. A normal palate was observed in 57 fetuses (78.1%). The mean gestational age was 27 weeks (range of 12 weeks to 39 weeks). All 16 fetuses with suspected cleft palate were confirmed by postnatal or autopsy findings, no false-positives were observed, and one case with a bifid uvula was missed among 57 fetuses with a presumed normal palate. Conclusions The fetal palate can be evaluated with 2D markers and 3D sonography. The detection of isolated cleft palate is more sensitive when 2D markers are present in all four planes.

Highlights Extrinsic doping is proposed as a novel route to enhance the intrinsic properties of the two-dimensional oxidized Si nanosheet (namely, siloxene) anode for Li-ion batteries. Fabrication of P-doped n-type siloxene is revealed to be possible through selective nucleophilic substitution of Si atoms in siloxene with P atoms. Due to boosted charge transport kinetics, n-type siloxene (6.7 × 1019 P atoms cm-3) exhibits the excellent storage performance (594 mAh g-1 after 500 cycles) even at 2000 mA g-1.

Highlights: Extrinsic doping is proposed as a novel route to enhance the intrinsic properties of the two-dimensional oxidized Si nanosheet (namely, siloxene) anode for Li-ion batteries. Fabrication of P-doped n-type siloxene is revealed to be possible through selective nucleophilic substitution of Si atoms in siloxene with P atoms. Due to boosted charge transport kinetics, n-type siloxene (6.7 × 1019 P atoms cm-3) exhibits the excellent storage performance (594 mAh g-1 after 500 cycles) even at 2000 mA g-1. Doped two-dimensional (2D) materials hold significant promise for advancing many technologies, such as microelectronics, optoelectronics, and energy storage. Herein, n-type 2D oxidized Si nanosheets, namely n-type siloxene (n-SX), are employed as Li-ion battery anodes. Via thermal evaporation of sodium hypophosphite at 275 °C, P atoms are effectively incorporated into siloxene (SX) without compromising its 2D layered morphology and unique Kautsky-type crystal structure. Further, selective nucleophilic substitution occurs, with only Si atoms being replaced by P atoms in the O3≡Si–H tetrahedra. The resulting n-SX possesses two delocalized electrons arising from the presence of two electron donor types: (i) P atoms residing in Si sites and (ii) H vacancies. The doping concentrations are varied by controlling the amount of precursors or their mean free paths. Even at 2000 mA g−1, the n-SX electrode with the optimized doping concentration (6.7 × 1019 atoms cm−3) delivers a capacity of 594 mAh g−1 with a 73% capacity retention after 500 cycles. These improvements originate from the enhanced kinetics of charge transport processes, including electronic conduction, charge transfer, and solid-state diffusion. The approach proposed herein offers an unprecedented route for engineering SX anodes to boost Li-ion storage. [ABSTRACT FROM AUTHOR]

The electrochemical carbon dioxide reduction reaction (eCO2RR) can achieve carbon recycling through renewable electrical energy. Before releasing the full potential of eCO2RR, the electrocatalysts still need improvement in terms of catalytic activity, selectivity, and durability. Two‐dimensional (2D) crystalline materials show a high aspect ratio with well‐defined crystal structures, which are promising electrocatalysts for eCO2RR. In this review, we briefly discuss the typical 2D electrocatalysts for eCO2RR. Subsequently, we provide a summary of the different strategies to improve the catalytic performance of 2D crystalline electrocatalysts for creating and modulating active sites. Finally, we end this review with the current challenges and future opportunities of 2D crystalline materials in the eCO2RR. [ABSTRACT FROM AUTHOR]

Two-dimensional polymeric networks are a new class of polymers with interesting physicochemical and biological properties. They promise a wide range of future biomedical applications including pathogen interactions, drug delivery, bioimaging, photothermal, and photodynamic therapy, owing to their unique features, such as high surface area and multivalent interactions at nano-biointerfaces. In this work, a thermosensitive two-dimensional polymeric network consisting poly(N-isopropylacrylamide) (pNIPAM) chains that are mechanically interlocked by a polyglycerol platform was synthesized and used for bacteria incapacitation. Two-dimensional hyperbranched polyglycerol (2D-hPG) was synthesized by a graphene-assisted strategy and used for encapsulation of azobisisobutyronitrile (AIBN). Radical polymerization of N-isopropylacrylamide by encapsulated AIBN resulted in thermoresponsive platforms with ~ 500 nm lateral size and 20–50 nm thickness. Due to its porous structure, 2D-PNPG was able to efficiently load antibiotics, such as tetracycline (TC) and amoxicillin (AMX). The rate of release of antibiotics from 2D-PNPG and the antibacterial activity of the system correlated with the variation of temperature as a result of the thermosensitivity of 2D-PNPG. This study shows that two-dimensional polymers are efficient platforms for future biomedical applications including drug delivery and bacteria incapacitation. Thermoresponsive two-dimensional nanomaterials with the ability of loading therapeutic agents and antibacterial activity are synthesized and characterized. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to develop a sonographic technique using two-dimensional (2D) markers for detecting isolated fetal cleft palate (no cleft lip) and to evaluate the ability of 2D and three-dimensional (3D) sonography to image the normal and abnormal palate. Methods: Seventy-three fetuses with a high risk of cleft palate at 12-39 weeks of gestation were referred for specialist ultrasound. A detailed evaluation of the palate was performed through 2D ultrasound, which revealed the appearance of the palatine line in the sagittal plane; the palate and alveolar ridge in the coronal plane of the fetal face; the horizontal plate of the palatine bone in the axial maxillary plane; and the soft palate in the transverse plane of the cavum pharyngis. Subsequently, 3D ultrasound imaging of the palate was performed in all fetuses. Antenatal diagnoses were compared with postnatal findings or autopsy findings. Results: Visualization of 2D markers was accomplished in all fetuses, and 3D assessment was achieved in 97% of fetuses. Cleft palate was suspected in 16 cases (21.9%), among which 14 were suspected on the basis of both 2D and 3D evaluation, and two were suspected only on the basis of 3D evaluation. A normal palate was observed in 57 fetuses (78.1%). The mean gestational age was 27 weeks (range of 12 weeks to 39 weeks). All 16 fetuses with suspected cleft palate were confirmed by postnatal or autopsy findings, no false-positives were observed, and one case with a bifid uvula was missed among 57 fetuses with a presumed normal palate. Conclusions: The fetal palate can be evaluated with 2D markers and 3D sonography. The detection of isolated cleft palate is more sensitive when 2D markers are present in all four planes. [ABSTRACT FROM AUTHOR]

Quantifying the mechanical properties of the cornea can provide valuable insights into the occurrence and progression of keratoconus, as well as the effectiveness of corneal crosslinking surgery. This study presents a non‐contact and non‐invasive wave‐based optical coherence elastography system that utilizes air‐pulse stimulation to create a two‐dimensional map of corneal elasticity. Homogeneous and dual concentration phantoms were measured with the sampling of 25 × 25 points over a 6.6 × 6.6 mm2 area, to verify the measurement capability for elastic mapping and the spatial resolution (0.91 mm). The velocity of elastic waves distribution of porcine corneas before and after corneal crosslinking surgery were further mapped, showing a significant change in biomechanics in crosslinked region. This system features non‐invasiveness and high resolution, holding great potential for application in ophthalmic clinics. [ABSTRACT FROM AUTHOR]

In recent years in the field of traditional materials, traditional polyaniline has faced a number of scientific problems such as an irregular morphology, high difficulty in crystallization, and difficulty in forming an ordered structure compared to the corresponding inorganic materials. In response to these urgent issues, this study determines how to prepare a highly ordered structure in polyaniline formed at the gas-liquid interface. By dynamically arranging aniline monomers into a highly ordered structure with sodium dodecyl benzene sulfonate (SDBS) surfactant, aniline polymerization is initiated at the gas-liquid interface, resulting in two-dimensional polyaniline crystal sheets with a highly ordered structure. By elucidating the microstructure, crystallization process, and molecular structure of the two-dimensional polyaniline crystal sheets, the practical application of polyaniline as an encryption label in the field of electrochromism has been further expanded, thus making polyaniline widely used in the field of information encryption. Therefore, the synthesis of flaky polyaniline crystal sheets has a role in scientific research and practical application, which will arouse the interest and exploration of researchers. [ABSTRACT FROM AUTHOR]

Next generation power system needs dielectrics with increased dielectric energy density. However, the low energy density of dielectrics limits their development. Here, an asymmetric trilayered nanocomposite, with a transition layer (TL), an insulation layer (IL), and a polarization layer (PL), is designed based on poly(vinylidene fluoride)-polymethyl methacrylate (PVDF-PMMA) matrix using KNbO3 (KN) and TiO2 (TO) as the nanofillers. The morphology and defect control of the two-dimensional nano KN and nano TO fillers are realized via a hydrothermal method to increase the composite breakdown strength (Eb) and the composite energy density (Ue). The asymmetric trilayered structure leads to a gradient electric field distribution, and the KN and TO nanosheets block charges transfer along z direction. As a result, the development path of the electrical trees is greatly curved, and Eb is effectively improved. And the Ue value of the nanocomposites reaches 17.79 J·cm−3 at 523 MV·m−1. On the basis, the composite Ue is further improved by defect control in TO nanosheets. The nanocomposite KN/TO/PVDF-PMMA containing TO with less oxygen vacancy concentration (calcined at oxygen atmosphere) acquires a high Ue of 21.61 J·cm−3 at 548 MV·m−1. This study provides an idea for improving the energy storage performance by combining the design of the composite dielectric structure and the control of nanofillers' defect and morphology. [ABSTRACT FROM AUTHOR]

Two-dimensional digital image analysis (DIA) considered a cost-effective method for characterizing the microstructure of asphalt mixtures. In this study, a more sophisticated method for defining the internal structure of aggregates was utilized to reveal performance-related properties that serve as quality indicators of mixtures. Software architecture-wise, Avizo19 is both modular and object-oriented has been used in this study. Modules and data objects are its key components. Metadata can be identified as or computational actions performed using modules. The study's goal is to assess the influence of laboratory vs. field compaction on the engineering qualities of several kinds of aggregates in different locations in central, northern, and southern Iraq including AlDoz, AlNibaa'e, Dyala, Jalawlaa, AlKut, AlSimawa, and Southern AlRumela quarries. Aviso analysis have been classified into two groups of parameters: geometric forms involving geometry, shape, and texture indicators, also the internal structure of aggregate interlocking, including orientation, anisotropy, homogeneity, and directional distribution of aggregate. The results of statistical comparisons of average, standard deviation (SD), and coefficient of variation (CoV) demonstrate the fact that the Roller compacting approach predicts the asphalt mixture formation indicators more significantly than the Marshall technique and is most effective within field compaction. [ABSTRACT FROM AUTHOR]

Sequentially timed all-optical mapping photography is one of the main emerging ultra-fast detection technologies that can be widely applicable to ultra-fast detection at the picosecond level in fields such as materials and life sciences. We propose a new optical structure for an all-optical spatial mapping module that can control the optical field of two-dimensional imaging while improving spectral resolution and detector sensor utilization. The model of optical parameters based on geometrical optics theory for the given structure has been established, and the theoretical analysis of the inter-frame energy crosstalk caused by incident beam spot width, chromatic aberration, and main errors of the periscope array has been conducted. The optical design of the two-dimensional (2D) all-optical spatial mapping module was finally completed using ZEMAX OpticStudio 2018 software. The results show that our optical module can realize targets of 16 frames and 1.25 nm spectral resolution. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) molybdenum disulfide (MoS2) holds great potential for various applications such as electronic devices, catalysis, lubrication, anti-corrosion and so on. Thermal evaporation is a versatile thin film deposition technique, however, the conventional thermal evaporation techniques face challenges in producing uniform thin films of MoS2 due to its high melting temperature of 1375 °C. As a result, only thick and rough MoS2 films can be obtained using these methods. To address this issue, we have designed a vacuum thermal evaporation system specifically for large-scale preparation of MoS2 thin films. By using K2MoS4 as the precursor, we achieved reliable deposition of uniform polycrystalline MoS2 thin films with a size of 50 mm × 50 mm and controllable thickness ranging from 0.8 to 2.4 nm. This approach also allows for patterned deposition of MoS2 using shadow masks and sequential deposition of MoS2 and tungsten disulfide (WS2), similar to conventional thermal evaporation techniques. Moreover, we have demonstrated the potential applications of the obtained MoS2 thin films in field effect transistors (FETs), memristors and electrocatalysts for hydrogen evolution reaction (HER). [ABSTRACT FROM AUTHOR]

In this study, a two-dimensional "double-horizon peridynamics" formulation was presented for membranes. According to double-horizon peridynamics, each material point has two horizons: inner and outer horizons. This new formulation can reduce the computational time by using larger horizons and smaller inner horizons. To demonstrate the capability of the proposed formulation, various different analytical and numerical solutions were presented for a rectangular plate under different boundary conditions for static and dynamic problems. A comparison of peridynamic and classical solutions was given for different inner and outer horizon size values. [ABSTRACT FROM AUTHOR]

Hydrogenation and fluorination is a significant method to tune the electronic properties of two-dimensional (2D) materials. This paper theoretically predicted and analyzed the effects and regulatory mechanisms of surface functionalization on the electronic properties of 2D semiconductor tetrahex Boron/Aluminium Nitride (th-BN/th-AlN). The density-functional theory (DFT) calculations were employed to study various trends of band structure, effective mass, and work function. The results show that the electronic properties of 2D th-BN/th-AlN are susceptible to the surface adsorption atom species and coverage. Interconversions between semiconductor and metal properties or indirect and direct band structures in 2D th-XN (X = B, Al) can be realized by hydrogen and fluorine surface adsorption. The band gap expands and the work function decreases after H atom is adsorbed on the surface, while the band gap first increases and then decreases and the work function expands after F is adsorbed on the surface. After functionalization, the effective mass of the hole will be reduced to even lighter than that of an electron in certain directions. The change mechanisms of electronic properties in th-BN/AlN is surface adsorbed atoms will cause sp2-hybridized atoms to turn into sp3-hybridized atoms, which leads to the polarized double bonds between adjacent atoms becoming a single σ bond. The chemical bond changing will result in the band near the Fermi level gradually disappearing.

Abstract Outstanding charge transport in molecular crystals is of great importance in modern electronics and optoelectronics. The widely adopted strategies to enhance charge transport, such as restraining intermolecular vibration, are mostly limited to organic molecules, which are nearly inoperative in 2D inorganic molecular crystals currently. In this contribution, charge transport in 2D inorganic molecular crystals is improved by integrating charge‐delocalized Se8 rings as building blocks, where the delocalized electrons on Se8 rings lift the intermolecular orbitals overlap, offering efficient charge transfer channels. Besides, α‐Se flakes composed of charge‐delocalized Se8 rings possess small exciton binding energy. Benefitting from these, α‐Se flake exhibits excellent photodetection performance with an ultrafast response rate (~5 μs) and a high detectivity of 1.08 × 1011 Jones. These findings contribute to a deeper understanding of the charge transport of 2D inorganic molecular crystals composed of electron‐delocalized inorganic molecules and pave the way for their potential application in optoelectronics.

This paper presents two-dimensional (2D) and three-dimensional (3D) numerical simulations of a half-scale geosynthetic reinforced soil (GRS) bridge abutment during construction and bridge load application. The backfill soil was characterized using a nonlinear elastoplastic model that incorporates a hyperbolic stress–strain relationship and the Mohr–Coulomb failure criterion. Geogrid reinforcements were characterized using linearly elastic elements with orthotropic behavior. Various interfaces were included to simulate the interaction between the abutment components. Results from the 2D and 3D simulations were compared with physical model test measurements from the longitudinal and transverse sections of a GRS bridge abutment. Facing displacements and bridge seat settlements for the 2D and 3D simulations agree well with measured values, with the 2D-simulated values larger than the 3D-simulated values due to boundary condition effects. Results from the 3D simulation are in reasonable agreement with measurements from the longitudinal and transverse sections. The 2D simulation can also reasonably capture the static response of GRS bridge abutments and is generally more conservative than the 3D simulation.

Two-dimensional materials have excellent optoelectronic properties and have great significance in the field of photodetectors. We have prepared a thin film photodetector based on bismuth telluride (Bi2Te3) topological insulator using dual-temperature-zone vapor deposition technology. Due to the high-quality lattice structure of Bi2Te3 and the uniform and dense surface morphology of the Bi2Te3 thin film, the device exhibits excellent photoelectric response and Vis–NIR spectral range. Under 405 nm illumination, the responsivity is 5.6 mA/W, the specific detectivity is 1.22 × 107 Jones, and the response time is 262/328 ms. We designed a photodetector single-point scanning imaging system and successfully achieved high-resolution imaging at a wavelength of 532 nm. This work provides guidance for the application of two-dimensional materials, especially Bi2Te3, in the fields of photodetectors and imaging.

Metal sulfide-based composites have become increasingly common as materials used for electrodes in supercapacitors because of their excellent conductivity, electrochemical activity, and redox capacity. This study synthesized a composite of NiFeS@MoS2@rGO nanostructure using a simple hydrothermal approach. The synthesized nanocomposite consisted of the composite of nickel sulfide and iron sulfide doped with MoS2@rGO. A three-electrode cell is employed to investigate the electrochemical properties of the NiFeS@MoS2@rGO electrode. The results demonstrated an optimal specific capacitance of 3188 F/g at 1.4 A/g in a 1 M KOH electrolyte. Furthermore, a supercapattery is designed utilizing NiFeS@MoS2@rGO//AC as the positive electrode and activated carbon (AC) as the negative electrode materials. The resulting supercapattery is designed at a cell voltage of 1.6 V, achieving a specific capacity value of 189 C/g at 1.4 A/g. It also demonstrated an excellent energy density of 55 Wh/kg with an enhanced power density of 3800 W/kg. Furthermore, the hybrid device demonstrated remarkable stability with a cycling stability of 95% over 30,000 charge–discharge cycles at a current density of 1.4 A/g. The supercapattery, which has excellent energy storage capabilities, is used as a power source for operating different portable electronic devices.

In the present work the atomic, electronic and optical properties of two-dimensional graphene, borophene, and boron carbide heterojunction bilayer systems (Graphene–BC3, Graphene–Borophene and Graphene–B4C3) as well as their constituent monolayers are investigated on the basis of first-principles calculations using the HSE06 hybrid functional. Our calculations show that while borophene is metallic, both monolayer BC3 and B4C3 are indirect semiconductors, with band-gaps of 1.822 eV and 2.381 eV as obtained using HSE06. The Graphene–BC3 and Graphene–B4C3 bilayer heterojunction systems maintain the Dirac point-like character of graphene at the K-point with the opening of a very small gap (20–50 meV) and are essentially semi-metals, while Graphene–Borophene is metallic. All bilayer heterostructure systems possess absorbance in the visible region where the resonance frequency and resonance absorption peak intensity vary between structures. Remarkably, all heterojunctions support plasmons within the range 16.5–18.5 eV, while Graphene–B4C3 and Graphene–Borophene exhibit a π-type plasmon within the region 4–6 eV, with the latter possessing an additional plasmon at the lower energy of 1.5–3 eV. The dielectric tensor for Graphene–B4C3 exhibits complex off-diagonal elements due to the lower P3 space group symmetry indicating it has anisotropic dielectric properties and could exhibit optically active (chiral) effects. Our study shows that the two-dimensional heterostructures have desirable optical properties broadening the potential applications of the constituent monolayers.