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• Two Fe3+ fluorescent probes based D-A type imidazole derivatives have been developed, which possessed a relatively great selectivity and sensitivity. • The probe molecules showed a relatively rare fluorescence color change response to Fe3+, its fluorescence changed from deep-blue to green. • The fluorescence sensing behavior of the probe molecules to Fe3+ was also applied to realize the rewritable paper in a very simple way. D-A type fluorescent probe usually shows a fluorescence quenching response to Fe3+, and relatively few probes can exhibit the fluorescence color change response. Herein, two high-luminescence D-A type imidazole derivatives TPABM and TPAFM were synthesized and used as Fe3+ fluorescent probes with an obvious fluorescence color change and remarkable sensing performance. Upon the addition of Fe3+, the original emission of TPABM and TPAFM was quenched, while a new emission peak emerged in the red-shifted direction, resulting in the fluorescence color changing from deep blue to green. This phenomenon may be caused by the coordination between the molecular imidazole ring and Fe3+ with a 1:1 ratio, which efficiently decreased the LUMO energy level of the probe molecules and formed a new CT emission with a lower energy gap. Furthermore, the probe molecules exhibited the potential for detecting Fe3+ in actual water samples and could be appropriated for the preparation of rewritable paper using a simple method. By using filter paper soaked with probe molecules as writing paper, Fe3+ aqueous solution as ink, and NaF aqueous solution as an eraser, the cycle of fluorescence writing and erasing was realized under UV irradiation. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile and scalable self-assembly of perylene diimide polymer with carbon paper. • Effective facilitation of carrier separation by π-π built-in electric field. • Narrowed band gap and low VB due to the VB tail states induced by π-π interactions. • Enhanced photocatalytic water oxidation activity of the PDIP/CP photocatalyst sheet. • Suitability of the PDIP/CP photocatalyst sheet for large-scale applications. Photocatalytic water splitting is a highly promising future energy technology. In contrast to the extensive work on particulate photocatalysts, there is still a lack of sufficient investigation for regularized photocatalysts. Here, from perylene diimide polymer (PDIP) and commercial carbon paper (CP), we develop a self-assembled PDIP/CP photocatalyst sheet that is easily scalable and can be used for photocatalytic water oxidation. Driven by strong interfacial π-π interactions, the PDIP spontaneously adsorbs onto the CP, which leads to a narrowed band gap, down-shifted VB edge, and enhanced separation of the photogenerated charge carriers of the PDIP. Under visible light, the PDIP/CP photocatalyst sheet shows significantly enhanced photocatalytic water oxidation activity (4 h cumulative oxygen evolution is 1.7 times higher than that of the powder-suspended system) and considerable cycling stability. The PDIP/CP photocatalyst sheet has the potential for large-scale device applications. [ABSTRACT FROM AUTHOR]

A novel colorimetric-fluorescent dual-mode sensing sensor JT5 was successfully synthesized, and exhibited red fluorescence enhancement effect and red colorimetric sensing, and excellent applicability through solid-state fluorescent strips and biological imaging experiments on zebrafish to highly sensitive monitoring Sn4+ ions. [Display omitted] • A novel and effective rhdamine B-based sensor JT5 successful development. • JT5 can serve as a fluorescent and colorimetric on-off sensor for Sn4+. • The sensor JT5 was successfully studied using fluorescence and colorimetric of the test strips. • Biomaging experiments for the sensor JT5 were conducted on zebrafish using a confocal microscope. A novel colorimetric-fluorescent dual-mode chemosensor (JT5) based on rhodamine B has been produced for monitoring Sn4+ in the DMSO/H 2 O (4:1, v/v) medium. It has high sensitivity, a low detection limit, a short response time (1 s) and high stability, and can still be maintained after two weeks with the red dual fluorescence/ colorimetric response. Enhancement of red fluorescence (591 nm) and red colorimetric (567 nm) response of JT5 by Sn4+ addition. The electrostatic potential of the sensor JT5 molecule was simulated to speculate on the sensing mechanism, and the IR, mass spectrometry and 1H NMR titration were utilized to further demonstrate that JT5 was coordinated to Sn4+ with a 1:1 type, the rhodamine spironolactam ring of JT5 opens up to form a penta-membered ring with Sn4+, meanwhile, its system may have chelation enhanced fluorescence (CHEF) effect. In addition, theoretical calculations were carried out to give the energy gaps of JT5 and [ JT5 + Sn4+] as well as to simulate the electronic properties of the maximal absorption peaks. Notably, the sensor JT5 was successfully applied to monitoring Sn4+ in zebrafish, and the JT5 -loaded filter paper provided a solid-state platform for detecting Sn4+ by both naked eye and fluorescent methods. In summary, this work contributes to monitoring Sn4+ in organisms and solid-state materials and promotes understanding of Sn4+ functions in biological systems, environments, and solid-state materials. [ABSTRACT FROM AUTHOR]

Optical eigenstates with a high quality (Q) factor provide substantial advantages for a broad spectrum of optical devices, particularly those demanding strong light–matter interactions. Recently, it has been demonstrated that ultrahigh- Q resonances can be realized in planar photonic structures by merging multiple bound states in the continuum (BICs) in the momentum space. Photonic lattices with thin-film geometry are known to support abundant TE-polarized and TM-polarized BICs. While prior research has explored the merging of TE-polarized BICs, this paper presents analytical and numerical results concerning the merging of TM-polarized BICs in laterally periodic one-dimensional photonic lattices. As the thickness of photonic lattices increases, TM-polarized accidental BICs descend along the dispersion curves and eventually merge at the upper edge of the second stop band. Employing coupled-mode analysis, we calculate the analytical merging thickness at which multiple TM-polarized BICs come together at the second-order Γ point. We confirm the merging of TM-polarized BICs through finite-element method simulations. Our results can be beneficial for achieving ultrahigh- Q resonances through the merging of BICs. [ABSTRACT FROM AUTHOR]

Based on the hexagonal honeycomb structure and the tri-ligament chiral honeycomb structure, this paper proposes a hybrid material structure with low-frequency elastic wave suppression below 100 Hz. Based on the finite element method and Bloch's theorem, the energy band structure was calculated, and the formation of the band gap and the wave-propagation properties of the structure were carefully studied, the wave attenuation performance of the composite structure was simulated, and the influence of material properties and geometric parameters on the width and position of the band-gap distribution was discussed. The results show that the structure can generate a good band gap in the low-frequency range of 100 Hz, and the wave propagation is suppressed obviously. Demonstrating its potential in practical applications, the research in this paper provides a theoretical basis for the manufacture of low-frequency vibration damping equipment and instruments, and provides a scheme for the design of metamaterials with low-frequency band gaps. [ABSTRACT FROM AUTHOR]

When the level of reactive oxygen species (ROS) increases abnormally in the body, it damages tissue cells and is closely related to the occurrence of various chronic diseases. Antioxidant peptides (APs) are a class of active short peptides with antioxidant capacity, which have great research value. In this paper, two APs were designed and synthesized based on the structural features of APs: CHIWM (AP1) and CHCPWM (AP2). The reactive sites and activities of APs were analyzed using the quantum chemical density functional theory (DFT) method. The reactive sites are all located in the indolyl heterocycle of tryptophan residues, among which AP1 has a smaller energy gap and single point energy. Multiple free radical scavenging assays showed that AP1 and AP2 had stronger antioxidant activity than the positive control, glutathione (GSH). For scavenging DPPH free radicals, the IC50s values were 0.613 mg/mL and 0.606 mg/mL, respectively. In cellular assays, both AP1 and AP2 were able to scavenge ROS in the cells and attenuate cellular damage. In conclusion, AP1 and AP2 designed in this paper have good antioxidant activity and have the potential to be applied in the treatment of chronic diseases caused by cellular oxidative damage. [ABSTRACT FROM AUTHOR]

The polymer semiconductor material known as graphitic carbon nitride (g-C3N4) has been extensively utilized for the removal of pollutants in wastewater treatment due to its notable visible photocatalytic efficiency, cost-effectiveness, straightforward synthesis, and chemical robustness. Nonetheless, unmodified g-C3N4 still exhibits deficiencies including suboptimal visible light absorption, pronounced electron-hole recombination, and wide band gaps, resulting in constrained photocatalytic efficacy. Through extensive research efforts, diverse modification approaches have been devised to enhance its photocatalytic capabilities. This paper systematically introduces the development history, preparation methods, photocatalytic mechanisms, advantages, and disadvantages of novel g-C3N4 materials, the various modification strategies including morphology control, element doping, defect construction, semiconductor coupling, and hetero-structure construction. In this paper, the preparation process, characterization results, practical applications, and performance enhancement effects of various elementally doped g-C3N4 materials in pollutant removal are discussed in detail, indicating the advantages of multielement doping modification strategy have obvious advantages in improving the photocatalytic performance of g-C3N4, highlighting the future prospects of g-C3N4 materials. [ABSTRACT FROM AUTHOR]

Co-doping of phosphorus and boron elements into crystalline silicon quantum dot (c-Si QD) is an effective approach for enhancing the photoluminescence (PL) performance. In this paper, we report on the preparation of hydrogenated silicon nitride (SiNx:H) thin films embedded with phosphorus-boron co-doped c-Si QDs via plasma enhanced chemical vapor deposition route. Mixed dilution including hydrogen (H2) and argon (Ar) is applied in the in-situ deposition process for optimizing the deposition process. The P-B co-doped c-Si QD/SiNx:H thin films exhibit a wide range of PL spectra. The emission is greatly improved especially for the short-wavelength light when compared to the SiOx:H thin film containing P-B co-doped c-Si QDs. The effects of H2/Ar flow ratio on the structural and optical characteristics of thin films are systematically investigated through a series of characterizations. Experimental results show that various properties, such as crystallinity, QD size, optical band gap and doping concentrations, are effectively controlled by tuning H2/Ar flow ratio. Based on the red-shift of QCE-related PL peak, the successful P-B co-doping into Si QDs are verified. Finally, a comprehensive discussion has been made to analyze the influence of H2-Ar mixed dilution on the film growth and impurity doping in detail in this paper. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) piezoelectric nanomaterials have widely been studied recently due to their promise for various applications in technology. Investigation of vertical piezoelectricity will contribute to a deeper understanding of the intrinsic mechanism of piezoelectric effects in the 2D structures. In this paper, we report a first-principle study for the structural, electronic, piezoelectric, and transport properties of new-designed Janus WSi Z 3 H (Z = N, P, and As) monolayers. The structural stability of WSi Z 3 H is theoretically confirmed based on the energetic, phonon dispersion, and also elastic analyses. At the ground state, while WSiN 3 H is an indirect semiconductor, both WSiP 3 H and WSiAs 3 H are predicted to be direct semiconductors with smaller bandgaps. When the spin-orbit coupling effects are taken into account, a large valley spin splitting is observed at the K point of WSi Z 3 H materials. Interestingly, a giant Rashba spin splitting is found in WSiP 3 H and WSiAs 3 H with Rashba constant α R up to 770.91 meV Å. Additionally, our first-principles study indicates that Janus WSi Z 3 H monolayers are piezoelectric semiconductors with high out-of-plane piezoelectric coefficient | d 31 | , up to 0.15 pm/V, due to the broken mirror symmetry. Besides, with high electron mobilities and also possessing direct band gaps, WSiP 3 H and WSiAs 3 H monolayers are favorable for applications in optoelectronics. [ABSTRACT FROM AUTHOR]

This paper reviews sintered silver (s-Ag) die-attach materials for wide band gap (WBG) semiconductor packaging. WBG devices that die-attach with s-Ag have attracted a lot of attention owing to their low energy loss and high temperature operation capabilities. For their practical operation, a reliability design should be established based on the failure of physics of the s-Ag die layer. This paper first focuses on the material characteristics of the s-Ag and tensile mechanical properties. Then, the s-Ag die-attach reliability is assessed with high-temperature storage, power cycling, and thermal shock tests. Each fracture mode was discussed by considering both the fracture surface analysis results and its mechanical properties. Finally, the effective reliability design parameters of the s-Ag die layer are introduced. [ABSTRACT FROM AUTHOR]

Context: The key factor in designing heat-resistant energetic materials is their thermal sensitivity. Further research and prediction of thermal sensitivity remains a great challenge for us. This study is based on first-principles calculations and establishes a theoretical model, which comprehensively considers band gap, density of states, and Young's modulus to obtain a empirical parameter Ψ. A quantitative relationship was established between the new parameter and the thermal decomposition temperature. The value of Ψ is calculated for 10 energetic materials and is found to have a strong correlation with the experimental thermal decomposition temperature. This further proves the reliability of our model. Specifically, the larger the value of Ψ, the higher the thermal decomposition temperature, and the more stable the energetic material will be. Therefore, to some extent, we can use the new parameter Ψ calculated by the model to predict thermal sensitivity. Methods: Based on first-principles, this paper used the Cambridge Serial Total Energy Package (CASTEP) module of Materials Studio (MS) for calculations. The Perdew-Burke-Ernzerhof (PBE) functionals in Generalized Gradient Approximation (GGA) method as well as the Grimme dispersion correction was used in this paper. [ABSTRACT FROM AUTHOR]

An epoxy-based metamaterial plate structure with local resonance is designed in this paper. The bandgap of the bending wave ranges from 36.46Hz to 110.55Hz. Through the optimization design of the oscillators in the plate structure, the starting bandgap moves to 19.79Hz, and the band gap width is 72Hz. The dispersion curve and frequency response function were calculated by finite element method (FEM). On this basis, the plane wave expansion method formula of the structural model was derived, and the equivalent model of spring-mass model was established. The results show that the calculation results of the three methods of the epoxide metamaterial plate structure were basically consistent, and the correctness of these methods was verified mutually. The methods derived in this paper bring great convenience and diversity to the application of plate structure. The article proposes a low-frequency wide bandgap thick plate structure model. [ABSTRACT FROM AUTHOR]

This paper introduces a structural design which has superior energy harvesting ability. The proposed structure is based on the ability of most periodic structures to prohibit elastic waves from propagating in a specific frequency range of the phonon band gap. By leading into acoustic black hole (ABH) units and utilizing the energy concentration characteristics of the ABH structure, the filtering effect can be made more significant. These two characteristics can produce significant strain and energy localization, which is conducive to energy harvesting. In this paper, we obtained ABH unit capable of producing broadband gaps by adjusting the geometric parameters of the ABH structure, and chose a cantilever as the research object for energy harvesting, by applying a piezoelectric patch on the unit located near the fixed end to gain a broader application in the actual situation. The results show that the beam combining the energy concentration characteristics of band gap and ABH structure has a significant improvement in energy harvesting efficiency. Optimization on the parameters of ABH unit shows that the band gap characteristic of the periodic ABH structure can further optimize the energy harvesting efficiency of practical energy harvesters, and opens up a new possibility of energy harvesting of ABH structure. [ABSTRACT FROM AUTHOR]

The research addresses the pressing need to understand wind conditions for optimal wind energy utilization, a crucial aspect of achieving global energy sustainability. While previous studies have focused on assessing wind energy potential and terrain roughness, gaps persist in understanding how wind and spatial conditions affect blade geometry. Therefore, this study aims to investigate the impact of local wind conditions on wind turbine blade geometry, integrating nonuniform wind inflow due to wind shear into the theoretical model. Through the paper, it explores blade design for varying inflow conditions and analyses the relationship between terrain type and blade designs. A novel approach to wind turbine blade design, utilizing a theoretical model that combines the local momentum theorem with insights from propeller vortex theory was adopted. Through the analysis, the authors demonstrate that variations in terrain significantly influence blade geometry, underscoring the necessity for tailored turbine designs based on local conditions. The findings reveal discrepancies in blade geometry across different turbine capacities and terrain types, offering novel insights into wind turbine performance optimization. By tailoring blade geometry to specific locations enhances resource utilization, offering insights for energy policymakers. The research provides validated methods for optimizing turbine geometric parameters, opening avenues for increased local investment in wind energy and promoting distributed energy development. Illustrated with wind plants examples, the paper concludes by outlining future research directions in this field. [ABSTRACT FROM AUTHOR]

Iron hydroxide (Fe(OH)3) nanoparticles have garnered considerable attention for their effectiveness in water treatment. This paper reviews recent studies on the photocatalytic degradation of phenol using Fe(OH)3, detailing the synthesis procedure, photocatalytic reaction conditions under UV‐C and catalyst amount optimization. Iron hydroxide was synthesized using a facile precipitation method, and the produced catalyst was thoroughly characterized using XRD, FTIR, UV‐DRS, DTA/TGA and SEM. Characterization results indicated that the catalyst exhibited very low crystallinity, a 1.84 eV band gap, and very small particle sizes. The study investigated the degradation performance of phenol for different amounts of iron hydroxide, ranging from 0.1 g to 1 g, and determined the optimum catalyst amount to be 0.7 g. The catalyst demonstrated a degradation efficiency for phenol exceeding 90 % at the end of a 180 minute photocatalytic reaction. The paper offers a comprehensive analysis of Fe(OH)3 as a photocatalyst for phenol degradation, highlighting its potential for future applications in water treatment. [ABSTRACT FROM AUTHOR]

Periodic structures are a type of metamaterial in which the physical properties depend not only on the details of the unit cell but also on how unit cells are arranged and interact with each other. In conventional engineering structures, each unit cell interacts with adjacent cells. Methods developed for vibrational and wave propagation analysis in periodic engineering structures consider only nearest-neighbor interactions. The dispersion curves of such systems, in which only adjacent cells interact, have been extensively studied. Metamaterial properties depend on the interactions of a unit cell with other cells. Further interactions, and specifically, interactions beyond the closest neighbors, imply a more complex band structure and wave behavior. In this paper, an example class of such structures, in which electrostatic forces are the driving force, has been investigated. In this paper, properties affecting these periodic structures, such as elastic forces, have been investigated. An attractive property of such structures is that the band structures of such metamaterials can be tuned by changing electric voltages. [ABSTRACT FROM AUTHOR]

In the present paper, we have conducted both theoretical and experimental investigations on thin films of lead sulfide (PbS). The structural and morphological properties of these films, which were prepared using the spray pyrolysis method, were analyzed utilizing X-ray diffraction (XRD) and scanning electron microscopy (SEM). Theoretical calculations were performed employing the first principles full potential linearized augmented plane wave (FP-LAPW) approach. The findings of this study reveal that the PbS film that was deposited is polycrystalline and possesses a rock-salt structure. The SEM image depicts a planar structure with dimensions ranging from 480 to 930 nm. The results obtained through energy dispersive spectroscopy (EDS) indicate high crystalline quality, and the film surface exhibits a rough texture and a dense morphology. In terms of its behavior, PbS acts as a semiconductor with a direct optical band gap situated at the L point of the Brillouin zone (BZ). The density of states on both sides of the band gap is primarily of s-p character. The ionic nature of PbS can be attributed to charge transfer. A substantial level of agreement has been observed between the experimental and theoretical results. Our ongoing research endeavors aim to explore biosensors and their various applications. The novelty of this work lies in the combined study of the structural and morphological properties of PbS films grown using the spray pyrolysis technique, employing both experimental and theoretical approaches. This paper describes a comprehensive approach to understanding bulk and thin-film PbS materials through theory and experimentation. [ABSTRACT FROM AUTHOR]

Context: In this paper, we systematically studied the effects of non-metallic element (B, C, N, O, F) doping and biaxial stretching on the photoelectric properties of ZrS2/ZrSe2 heterostructures by using the first-principles calculation method based on density functional theory. The results show that the p-type doping is realized by B, C, and N atom doping, and the n-type doping is realized by O and F atom doping. The doping of B and C atoms produces impurity energy levels in the band gap, which affects the conductivity of the heterostructure. The band gap of N and O atom–doped heterostructures increases under tensile strain, but it is still a direct band gap. The analysis of the optical properties of the heterostructures shows that the doping of non-metallic atoms can adjust the optical absorption rate and reflectivity of the heterostructures. Under the action of tensile strain, the optical properties of the doped heterostructures have changed significantly in the low-energy region. This article provides a theoretical basis for the future application of ZrS2/ZrSe2 heterostructures. Method: This paper uses the first-principles calculation method based on density functional theory. The PBE exchange-correlation functional based on generalized gradient approximation (GGA) is selected for the specific calculation, and the crystal structure is geometrically optimized by the ultrasoft pseudopotential method. It is verified that when the cutoff energy of the ZrS2/ZrSe2 heterostructure is 500 eV, the K-point grid is selected to be 10 × 10 × 2 with the lowest energy, so the cutoff energy is selected to be 500 eV. The K-point grid is selected to be 10 × 10 × 2. The convergence limits for structural optimization are as follows: the maximum force between atoms is 0.01 eV/Å, the convergence threshold of the maximum energy change is set to 10−9 eV/atom, and the convergence threshold of the maximum displacement is 0.001 Å. In order to avoid the influence of atomic periodic motion between different atomic layers, a vacuum layer of 20 Å is added in the vertical direction. Considering the interaction of vdW between the interfaces, the DFT-D2 method is used to verify. The optical properties were calculated by the random phase approximation method, and the K-point grid was selected as 12 × 12 × 2. [ABSTRACT FROM AUTHOR]

Recent works exploiting photonic valley Hall effect show that large-area topological states can be realized by inserting gapless photonic crystal structures into topological interfaces, thus effectively introducing mode width degree of freedom. However, the previously reported works focus on gapless edge states. It is rare to investigate gapped edge states, especially large-area gapped edge states. In this paper, large-area gapped edge states in a valley photonic crystal heterostructure are achieved and experimentally proved. Compared with large-area gapless topological states, the present gapped edge states are more localized, which provides a more effective way to manipulate electromagnetic waves. We implement a topological energy concentrator and topological resonator cavity based on the large-area topological transmission with the gapped edge states. It is expected that our results broaden photonic systems, which can be used in topological lasing, field enhancement, and high-capacity energy transport. [ABSTRACT FROM AUTHOR]

In order to extend the photo-shielding range of ceria from the ultraviolet (UV) region (≤400 nm) to the high-energy short-wave blue light (BL) region (400–450 nm), three groups of ceria-based materials, including ceria nanoparticles (nano-CeO 2), cerium-oxygen-sulfur (Ce-O-S) composites and samarium-cerium-oxygen-sulfur (Sm-Ce-O-S) composites, were prepared from the perspectives of improving the preparation method, non-metal doping and metal/non-metal co-doping. Although the three groups of as-prepared samples have similar phase composition, morphology and pore structure, the Sm-Ce-O-S composites show remarkable double shielding performance for UV light and short-wave BL. Compared with nano-CeO 2 and Ce-O-S composites, Sm-Ce-O-S composites that retains the characteristics of n-type semiconductor exhibits a greater degree of lattice distortion, higher concentrations of Ce3+ (41.17 %) and oxygen vacancy (77.29 %), and narrower band gap (2.71 eV). Through the comparison of the three groups of samples, the order of modification degree from high to low is as follows: metal/non-metal co-doping > non-metal doping > improving the preparation method. This paper provides experimental and theoretical support for breaking through the bottleneck of ceria in the fields of UV shielding agents and catalysts. [ABSTRACT FROM AUTHOR]

With the rapid development of global economy and industrialization, the management and protection of water resources have become increasingly important. In this paper, a novel three-dimensional Chitosan/Fe 3 O 4 /TiO 2 @MXene photocatalyst with excellent degradation and bacterial inhibition properties was prepared by a simple one-step hydrothermal method using FeCl 3 ·6H 2 O, Chitosan (CS) and MXene (Ti 3 C 2) as main raw materials. TiO 2 was generated in-situ on the surface of Ti 3 C 2 nanosheets and modified by loading Fe 3 O 4 nanoparticles and CS films. The conformations and band gaps of the composites were modified, and then photocatalytic mechanisms, phase compositions, morphological structures, magnetic properties and photoelectrochemical properties of the photocatalysts were systematically analyzed. The degradation efficiency of the CS/Fe 3 O 4 /TiO 2 @Ti 3 C 2 composite photocatalyst can reach 95.9 % when the ration of CS to FeCl 3 ·6H 2 O is 1:3 and the hydrothermal temperature is 180 °C, which showing excellent photocatalytic performance. Meanwhile, the inhibition rate of Staphylococcus aureus (S. aureus) is close to 98.91 % under the light condition. This study further reveals that visible light is a cost-effective way to treat pollution in terms of degradation and bacteriostatic inhibition, and the composite photocatalysts can be efficiently recycled and reused under the action of a magnetic field. [Display omitted] • CS/Fe 3 O 4 /TiO 2 @MXene with excellent degradation and bacteriostatic properties was synthesized by one-step hydrothermal method. • Fe 3 O 4 formed Schottky heterojunction with TiO 2 generated in situ, CS formed a double-layer film regulation system with Ti 3 C 2. • Bacteriostatic system was built: Nanoparticles brought ROS, loaded on sharp sheets, wrapped by CS with positive charges. • The material also has outstanding cyclic degradation performance, can be easily recycled and reused due to its magnetism. [ABSTRACT FROM AUTHOR]

In this paper, summarise the characterization and synthesis of the pure and Eu:WO 3 nanoparticles and their applications in photocatalytic and antibacterial activity. The monoclinic phase confirmed by the XRD analysis of the prepared specimens. SEM and HR-TEM scrutiny revealed nanoplate morphology scrutiny. EDS and XPS scrutiny confirmed the composition of elements of Eu, O, and W. FTIR analysis likely used for additional confirmation of functional groups. UV–Vis Analysis determined the band gap energy (Eg) of the nanoparticles, which decreased with raising the concentration of Eu doping. Optical properties of the band gap energy decreased with raising the concentration of Eu doping. Photocatalytic activity of the nanoparticles exhibited high photocatalytic activity, with a 95.3 % methylene blue (MB) dye split when exposed to visible light. The Eu:WO 3 (7 wt%) nanoparticles showed the best photocatalytic property within 120 min. The Eu:WO 3 (7 wt%) nanoparticles showed the maximum antibacterial efficiency against Staphylococcus aureus , with a zone of embarrassment of 19 mm. Overall, the study demonstrates the successful synthesis of Eu-doped WO 3 nanoparticles and their potential applications in photo catalysis and antibacterial activity, with promising results particularly at higher Eu doping concentrations. [ABSTRACT FROM AUTHOR]

Radiation shielding glass is an interesting material in the field of radiation shielding due to its remarkable features. In the present paper, we investigated the physical properties of radiation-shielding glass materials that consist of sodium oxide (Na 2 O), cerium oxide (CeO 2), and iron oxide (Fe 2 O 3) incorporated into borosilicate glasses with the formula 90SiO 2 -(70-x)B 2 O 3 + 20Na 2 O–1Fe 2 O 3 -xCeO 2 (CeFeNaBS-glasses). One of the distinguishing characteristics of this glass system is its enhanced radiation shielding capabilities. The structural studies indicated a gradual rise in glass density from 1.954 to 2.658 g/cm with further CeO 2 doping. Optical studies showed that the optical band gaps went down from 3.41 eV to 3.33 eV as the amount of CeO 2 in the CeFeNaBS-glass matrix rose. The decrease in optical band gap has been correlated with the rising basicity. Also, the increased basicity behavior induces more conversion of Ce3+ to Ce4+ ions by losing a 4f electron. Moreover, with further CeO 2 additions, the glass color changed from light brown to dark brown. The presence of Ce4+ ions with further CeO 2 additions is responsible for this color transformation. The linear and non-linear refractive indices exhibit enhanced behaviors with higher CeO 2 concentrations. We used declining basicity and polarizability behaviors to describe this behavior. The incorporation of larger CeO 2 concentrations enhances the ability to improve radiation shielding properties, as demonstrated by the increased values of the mass attenuation coefficient and half-value layer, especially in the energy ranges of soft tissues X-ray and hard tissues X-ray. Hence, the investigated CeFeNaBS-glasses exhibit enhanced transparency and radiation shielding capabilities, rendering them highly suitable for implementation in this domain. [ABSTRACT FROM AUTHOR]

With the rapid development of cities, metro transportation has also developed rapidly to solve the congestion problems caused by urban development. However, with the continuous development of metro transportation, the vibration problems caused by it have become increasingly obvious. Based on the phonon crystal theory, this paper investigates the vibration characteristics of the metro track structure. It analyzes the influence of the track structure parameters on the band gap characteristics to regulate the metro vibration band gap range. To study the band gap characteristics of metro monolithic bed track structure, establish the double-layer Euler beam model and use the plane wave expansion method (PWE) to calculate its energy band structure; use the finite element method (FEM) to calculate to get its band structure, frequency response function, and time domain analysis. The calculation of PWE shows that there is a band gap in the range of 0–300 Hz for the metro monolithic track bed, which is 0–194.5 Hz; the calculation of FEM shows that the range of band gap is 0–193.7 Hz. Fastening spacing, stiffness, and sub-slab support stiffness will have an impact on the band gap, so appropriate fastening and spacing need to be selected for effective vibration damping of the track structure. The results show that the band gap characteristics of the metro monolithic track bed can be calculated effectively and accurately by using the phononic crystal theory. [ABSTRACT FROM AUTHOR]

In this paper, we study the effects of different doping concentrations of O, Se, and Te atoms on the electronic structure and optical properties of single layer WS2 based on the density generalization theory of the first principles. The most stable structure. The system doped with Te atoms shows a shift from direct to indirect band gap, and the band gap of the system doped with Se atoms increases slightly. When investigating the optical properties, we also found that the absorption of light in each doped system mostly occurs in the ultraviolet region, and the absorption of light in the system doped with O atoms decreases, while the absorption of light in the system doped with Se and Te atoms changes with different frequencies. The reflectivity is higher than the intrinsic state. [ABSTRACT FROM AUTHOR]

The development of high‐performance ion battery anode materials is conducive to the rapid development of urban rail transit. Based on first‐principles calculations, this paper studies the potential performance of the recently discovered two‐dimensional material SnSe2 as a negative electrode for zinc ion batteries. By calculating the adsorption energy, the most stable adsorption configuration of Zn was determined. The band gap of intrinsic SnSe2 decreases after strain, which promotes the transition of carriers. The band gap opens after the strain occurs in the Zn adsorbed SnSe2 system (Zn‐SnSe2), which confirms the regulation of strain on the band gap. The lowest diffusion barrier of Zn is 0.083 eV. The theoretical zinc storage capacity is calculated to be 387.550 mAh/g. The calculation results provide theoretical parameters for the application of SnSe2 in ion batteries. [ABSTRACT FROM AUTHOR]

In this paper, detailed models of GaTe/XSe heterojunctions are constructed and geometrically optimised. The GaTe/InSe(X = Zn, In) heterojunction is calculated to be a Type-II direct bandgap semiconductor with a forbidden bandwidth of 1.26 eV based on the DFT study, while the GaTe/ZnSe heterojunction behaves as a Type-II indirect bandgap semiconductor with a forbidden bandwidth of 0.899 eV. The forbidden bandwidth reaches its maximum value at 2% of tensile strain. When the compressive strain reaches −8%, the forbidden bandwidth is 0 and the heterojunction is converted from a semiconductor to a conductor. The analysis of the absorption spectra of GaTe/InSe and GaTe/ZnSe heterojunctions shows that both heterojunctions increase the absorption in the visible region as well as broaden the absorption range of the spectrum. Therefore, GaTe/InSe heterojunctions are useful in the field of optoelectronic devices. • The band gap width of the GaTe/InSe heterojunction is calculated to be 1.254 eV, and this heterojunction is a direct band gap semiconductor. The band gap width of the GaTe/ZnSe heterojunction is 0.899 eV, and this material is an indirect band gap semiconductor. • GaTe/ZnSe and GaTe/InSe heterojunctions have good optoelectronic properties with smaller bandgap widths and a wider range of light absorption. [ABSTRACT FROM AUTHOR]

Perovskite oxides LaFeO 3 has been considered as one of the most promising candidates as the negative electrode material of Ni/MH batteries, due to its advantages such as low cost, outstanding corrosion resistance and environmentally friendly. Nevertheless, the low electrical conductivities and poor specific capacities are the main obstacles of developing this material to practical application. Doping is an effective method to solve these problems. In this paper, nanosized LaFeO 3 -based solid solutions doped with Co3+, Mn3+, and Li+ ions were synthesized via sol-gel method, and the contents of the doped ions are set as 0.10. The substitution positions of the doped ions were discussed. The microstructure tests revealed that the doped samples were single phase structures, and the crystallite sizes of the doped samples were smaller than that of the undoped LaFeO 3. The dispersion degrees of the doped samples were improved. The results of the spectra tests demonstrated that the doped ions decreased the band gap energies, the Co3+ and Mn3+ ions influenced the frequencies of Fe–O stretching vibrations, and partial replacement of La3+ ions by Li+ ions induced the shift of vibration modes of the La–O bond. Electrochemical hydrogen storage measurements showed that the doped samples possess significantly better properties than that of the undoped LaFeO 3. Thereinto, the maximum discharge capacity of the Co3+ ion doped sample reached to 414 mAh/g at the 14th cycle and remained stable at around 400 mAh/g within the following cycles. Kinetic results further proved that the doped samples showed better performances. The hydrogen storage properties of doped LaFeO 3 are closely associated with the contents of the oxygen vacancies and defects in the lattice of samples. In addition, the characteristics of the doped ions also play important roles in improving the hydrogen storage properties of the LaFeO 3 -based oxides. [ABSTRACT FROM AUTHOR]

Based on the local resonance theory, the vibration isolation performance of four-component periodic pile barriers consisting of a matrix, an outer pipe, an inner pipe, and a pile core was investigated using the finite element method (FEM). This configuration is contrasted with traditional three-component periodic pile barriers, which are composed of a matrix, a pipe, and a pile core. The four-component systems demonstrate significantly broader bandgaps compared to three-component systems. To validate the efficiency of the FEM, model test on pile barriers were conducted, facilitating a comparison between the FEM and experimental observations of bandgap characteristics. Additionally, the effects of the outer pipe's density, elastic modulus, and thickness on the complete bandgap characteristics were comprehensively studied within the four-component structure. It is found that the broadest vibration isolation band gaps occur under hexagonal arrangement pattern. In square and hexagonal lattice configurations, the density, elastic modulus, and thickness of the outer pipe pile's pile have predominantly influenced the upper bound frequency (UBF). There has been a positive correlation between the elastic modulus and the UBF, while the density and thickness have shown inverse relationships. Moreover, there exists a elastic modulus threshold, marking a transition in the displacement mode of the UBF, from the outer irreducible Brillouin zone (M or X) to the inner zone (Γ). Once the threshold is exceeded, both the vibration displacement mode and the width of bandgap remain substantially unchanged. The results obtained in the present paper are very useful for the design and application of periodic pile barriers in ambient vibration reduction. [ABSTRACT FROM AUTHOR]

Pipeline structures usually suffer from serious vibration problems due to pressure pulsation and fluid excitation, potentially compromising their structural stability and service life. In this paper, a lightweight body center cubic (BCC) meta-lattice sandwich sleeve is proposed to isolate vibrations in pipelines within a broadband frequency range. The vibration isolation is based on the concepts of the locally resonant metamaterials. An equivalent mass-spring model is conducted to theoretically predict frequency range and elucidate the generation mechanism of the band gap. In addition, an analytical methodology is also proposed to predict the equivalent stiffness of the BCC meta-lattice sleeves. The influence of geometric parameters and configuration layout of the meta-lattice on the flexural wave band gap is further investigated. Numerical studies and experimental tests are also conducted to validate the vibration isolation effectiveness, considering various pipe lengths and different numbers of meta-lattice units. The proposed design provides fundamental support for the design of lightweight vibration isolation structure for pipelines. [ABSTRACT FROM AUTHOR]

Starting from the seminal works of Toupin, Mindlin and Germain, a wide class of generalized elastic models have been proposed via the principle of virtual work, by postulating expressions of the elastic energy enriched by additional kinematic descriptors or by higher gradients of the placement. More recently, such models have been adopted to describe phenomena which are not consistent with the Cauchy-Born continuum, namely the size dependence of apparent elastic moduli observed for micro and nano-objects, wave dispersion, optical modes and band gaps in the dynamics of heterogeneous media. For those structures the mechanical response is affected by surface effects which are predominant with respect to the bulk, and the scale of the external actions interferes with the characteristic size of the heterogeneities. Generalized continua are very often referred to as media with microstructure although a rigorous deduction is lacking between the specific microstructural features and the constitutive equations. While in the forward modelling predictions of the observations are provided, the actual observations at multiple scales can be used inversely to integrate some lack of information about the model. In this review paper, generalized continua are investigated from the standpoint of inverse problems, focusing onto three topics, tightly connected and located at the border between multiscale modelling and the experimental assessment, namely: (i) parameter identification of generalized elastic models, including asymptotic methods and homogenization strategies; (ii) design of non-conventional tests, possibly integrated with full field measurements and advanced modelling; (iii) the synthesis of meta-materials, namely the identification of the microstructures which fit a target behaviour at the macroscale. The scientific literature on generalized elastic media, with the focus on the higher gradient models, is fathomed in search of questions and methods which are typical of inverse problems theory and issues related to parameter estimation, providing hints and perspectives for future research. [ABSTRACT FROM AUTHOR]

In this paper, we describe the synthesis of cerium molybdate (Ce 2 (MoO 4) 3) and different compositions of Bi-doped cerium molybdate (Ce 2-x Bi x (MoO 4) 3) where x = 0.01, 0.03, 0.05, 0.07, and 0.09, through simple co-precipitation method. The synthesized materials were optically, structurally, and morphologically characterized by various sophisticated techniques, including UV–visible, FTIR, Raman, PXRD, BET, and SEM-EDX. Upon addition of bismuth, the optical band gaps are reduced from 3.35 eV (Ce 2 (MoO 4) 3) to 2.83 eV Ce 1.93 Bi 0.07 (MoO 4) 3. The charge storage potential and AC conductivity of the synthesized materials were investigated through dielectric studies where the dielectric constant increased by increasing dopant concentration up to 7 %. At 20 Hz, Ce 1.93 Bi 0.07 (MoO 4) 3 showed a significantly greater dielectric constant (3.597 × 106) compared to undoped Ce 2 (MoO 4) 3 (3.262 × 105). Similarly, the AC conductivity of Ce 1.93 Bi 0.07 (MoO 4) 3 increased up to 4.758 S m−1 compared to the undoped Ce 2 (MoO 4) 3 (2.270 S m−1) at 20 MHz. The photocatalytic efficiency was investigated against diclofenac potassium, which also considerably improved by increasing bismuth content. The maximum photodegradation efficiency of 87.9 % was observed for Ce 1.93 Bi 0.07 (MoO 4) 3 in 180 min under UV light irradiation at optimized conditions (pH = 4, catalyst dosage = 20 mg, and initial concentration of drug = 5 mg L−1). The photocatalytic reaction followed pseudo-first-order kinetics with a rate constant of 0.0108 min−1 with stability up to five successive runs of photocatalytic activity indicating its good recyclability. These findings suggest that Bi-doped cerium molybdate could be used as a promising material for photocatalysis and energy storage devices. [ABSTRACT FROM AUTHOR]

The availability of fresh water is limited compared to its huge consumption. Conversely, certain industries like dyes, textiles, paper, and tanning not only consume vast quantities of fresh water, but also generate significant amounts of wastewater that poses severe threats to living organisms. The present investigation focuses on the degradation of Rhodamine-B (Rh–B) as a model pollutant by using the nanocomposite based on waste scrap tire-derived activated carbon (AC) and titanium dioxide (TiO 2). These nanostructures were fabricated using wet chemistry techniques. Analysis using scanning electron microscopy (SEM) revealed that the morphology of the structures remained largely unchanged even with a concentration of 6 mg of AC. X-ray diffraction (XRD) results confirmed the successful fabrication of rutile and anatase phases of TiO 2 @AC nanocomposite. The XPS results confirmed the presence of AC and TiO 2 in the composite. Furthermore, the optical band gap of the nanocomposites decreased up to 17.17 % and 34.57 % through direct and indirect methods respectively, owing to the varying quantity of AC used. The narrowing of optical band gap and the increased surface oxygen vacancies were caused by the successive addition of AC during the synthesis of nanocomposites. This resulted in the efficient degradation of Rhodamine-B (Rh–B) using adsorption and photocatalytic oxidation. The findings demonstrate a significant influence of AC on the TiO 2 catalyst in the removal of Rh–B dye. The maximum efficiency of dye removal, reaching up to 99.14 %, was achieved with the highest concentration of AC, thus demonstrating almost complete elimination of Rh–B dye. The findings suggest that the use of waste scrap tires can be effectively applied to design efficient photocatalysts for addressing the wastewater management issues. [ABSTRACT FROM AUTHOR]

• A quasi-zero-stiffness (QZS) metamaterial cylindrical shell is proposed;. • Quasi-zero stiffness is fulfilled by compliant mechanisms;. • QZS resonator is devised to open low-frequency band gaps;. • QZS metamaterial shell enables wave attenuation at low frequency. Low-frequency vibrations widely exist in various shell structures of aircrafts, ships or rockets, and propagate along shell structures in elastic waves. Aimed at the vibration issue, this paper proposes a novel metamaterial cylindrical shell with quasi-zero-stiffness (QZS) resonators to achieve low-frequency wave attention within band gaps. Firstly, the resonator is devised to exhibit the QZS feature under appropriate pre-deformation. A simplified dynamic model is established to replace the metamaterial cylindrical shell and derive dispersion relations. Then, the band gap is revealed theoretically by both the plane wave expansion method (PWEM) and the finite element method (FEM). Additionally, the finite element model of the metamaterial cylindrical shell is built to analyze the structural responses and evaluate the transmittance of flexural waves. The results show that the QZS metamaterial cylindrical shell is capable of opening low-frequency band gaps and effectively attenuating flexural waves at low frequencies. [ABSTRACT FROM AUTHOR]

CsGeI2Br-based perovskites, with their favorable band gap and high absorption coefficient, are promising candidates for the development of efficient lead-free perovskite solar cells (PSCs). However, bulk and interfacial carrier non-radiative recombination losses hinder the further improvement of power conversion efficiency and stability in PSCs. To overcome this challenge, the photovoltaic potential of the device is unlocked by optimizing the optical and electronic parameters through rigorous numerical simulation, which include tuning perovskite thickness, bulk defect density, and series and shunt resistance. Additionally, to make the simulation data as realistic as possible, recombination processes, such as Auger recombination, must be considered. In this simulation, when the Auger capture coefficient is increased to 10−29 cm6 s−1, the efficiency drops from 31.62% (without taking Auger recombination into account) to 29.10%. Since Auger recombination is unavoidable in experiments, carrier losses due to Auger recombination should be included in the analysis of the efficiency limit to avoid significantly overestimating the simulated device performance. Therefore, this paper provides valuable insights for designing realistic and efficient lead-free PSCs. [ABSTRACT FROM AUTHOR]

The utilization of lithium-ion batteries (LIBs) is increasing sharply with the increasing use of mobile phones, laptops, tablets, and electric vehicles worldwide. Technologies are required for the recycling and recovery of spent LIBs. In the context of the circular economy, it is urgent to search for new methods to recycle waste graphite that comes from the retired electrode of LIBs. The conversion of waste graphite into other products, such as new electrodes, in the field of energy devices is attractive because it reduces resource waste and processing costs, as well as preventing environmental pollution. In this paper, new electrode materials were prepared using waste anode graphite originating from a spent mobile phone battery with an xBT·0.1C12H22O11·(0.9-x)(NH4)2HPO4 composition, where x = 0–50 weight% BT from the anodic active mass of the spent phone battery (labeled as BT), using the melt quenching method. Analysis of the diffractograms shows the graphite crystalline phase with a hexagonal structure in all prepared samples. The particle sizes decrease by adding a higher BT amount in the composites. The average band gap is 1.32 eV (±0.3 eV). A higher disorder degree in the host network is the main factor responsible for lower band gap values. The prepared composites were tested as electrodes in an LIB or a fuel cell, achieving an excellent electrochemical performance. The voltammetric studies indicate that doping with 50% BT is the most suitable for applications as electrodes in LIBs and fuel cells. [ABSTRACT FROM AUTHOR]

In order to achieve low frequency vibration and noise reduction, researchers have found and explored many types of metamaterial structures. Based on this, an innovative multiphase metamaterial structure composed of hard materials and soft materials is proposed in this paper. According to Bloch's theorem, the band gap characteristics of the proposed structure are calculated using the finite element method, and the formation mechanism of the band gap is analyzed. In addition, the effects of the stiffness and density of the two materials on the band gap are studied in detail. Then, the phase velocity, group velocity and wave propagation direction are calculated according to a certain frequency of the specific dispersion curve, and the important information of wave propagation in the structure is obtained. Finally, according to the transmission characteristics of vibration in a finite periodic structure, it is verified that the existence of band gap can inhibit the vibration transmission, and it is further clarified that the proposed structure has a good performance in the design of low-frequency band gaps with large amplitude. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper starts with the proposal of an enhanced version of a planar rectangular slot antenna fed by the quasi‐TEM printed ridge gap waveguide (PRGW), attended with a numerical study of a miniaturization procedure showing the limitations of the conventional PRGW‐based antennas. Then innovative solution is introducing a new miniaturized pure TEM wide‐band slot antenna utilizing double PRGW (D‐PRGW) technology; the proposed approach is self‐packaged and shows high potential for enhancing antenna performance, particularly in terms of bandwidth, gain, and compactness. This technology is featured with low loss, high performance, and compact size; it consists of surrounding the ridge area with a double layer of electromagnetic band gap (EBG) lattice instead of one to eliminate the surface waves effectively and keep the signal completely confined inside the ridge area with strict minimum rows of EBG. Therefore, a broad impedance matching bandwidth (|S11| ≤ −10 dB) of 33.33% is obtained from 50 to 70 GHz, which covers the unlicensed NR parts (n262; amp; n263) of the V band. Furthermore, the antenna achieves a peak gain of approximately 16 at 65 GHz while the overall efficiency remains above 90% across the entire operating frequency band. The high performance along with the compact size of this novel design makes it a good candidate for 5G wireless communications applications centered around 60 GHz. [ABSTRACT FROM AUTHOR]

Meeting the growing demand for robust, earth-abundant and noble-metal-free photocatalysts for practical hydrogen-evolution reaction systems is crucial. Herein, cation modified perovskite niobates, Na0.5Sr0.5M0.25Nb0.75O3 (M = Cr, Mn, Fe, Co), are synthesized using a simple heterovalent coupled substitution strategy via solid-state reactions. The Cr compound as a single semiconductor system exhibits a photocatalytic hydrogen evolution rate of 188 μmol h−1 g−1, which significantly surpasses the performance of many contemporary catalysts that rely on the use of noble metal cocatalysts. Apparent quantum efficiencies (AQEs) of Cr, Mn, Fe and Co containing compounds are 2.24, 0.55, 0.65 and 0.74%, respectively. The photophysical properties like tuned band gap, suitable energy level positioning, charge carrier density, photostability of the materials and charge transfer resistance that are responsible for efficient spatial charge separation and charge transfer dynamics impacting the hydrogen evolution are investigated. This paper discusses the role of cation modification and its effects on the photophysical properties and hydrogen evolution activity of the perovskite niobates under noble-metal free conditions. These nonprecious noble-metal-free perovskite niobates furnish a new perspective for the future design of photocatalysts for efficient photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

The single-layer MoS2 is a highly sought-after semiconductor material in the field of photoelectric performance due to its exceptional electron mobility and narrow bandgap. However, its photocatalytic efficiency is hindered by the rapid recombination rate of internal photogenerated electron–hole pairs. Currently, the construction of heterojunctions has been demonstrated to effectively mitigate the recombination rate of photogenerated electron–hole pairs. Therefore, this paper employs the first principles method to calculate and analyze the four heterojunctions formed by MoS2/WSe2, MoS2/MoSe2, MoS2/AlN, and MoS2/ZnO. The study demonstrates that the four heterojunctions exhibit structural stability. The construction of heterojunctions, as compared to a monolayer MoS2, leads to a reduction in the band gap, thereby lowering the electron transition barrier and enhancing the light absorption capacity of the materials. The four systems exhibit II-type heterojunction. Therefore, the construction of heterojunctions can effectively enhance the optical properties of these systems. By forming heterojunctions MoS2/WSe2 and MoS2/MoSe2, the absorption coefficient in the visible light region is significantly increased, resulting in a greater ability to respond to light compared to that of MoS2/ZnO and MoS2/AlN. Consequently, MoS2-based heterojunctions incorporating chalcogenide components WSe2 and MoSe2, respectively, exhibit superior catalytic activity compared to MoS2 heterojunctions incorporating non-chalcogenide components ZnO and AlN, respectively. The absorption spectrum analysis reveals that MoS2/MoSe2 exhibits the highest light responsivity among all investigated systems, indicating its superior photoelectric performance. [ABSTRACT FROM AUTHOR]

Compared to single-phase multiferroic materials, multiferroic (MF)-magnetoelectric (ME) composites, which combine magnetic and ferroelectric materials, show improved (many orders of magnitude) ME coupling and a higher operating temperature (beyond room temperature). In the present study, lead-free multiferroic Ni0.5Co0.5Fe2O4/BaTiO3 (NCFO/BTO) composites with different weight percentages were prepared through the solid-state reaction approach. The phase purity and structural confirmation were carried out using X-ray diffractograms. The XRD peak shifting in the composites has been observed, and it is attributed to the formation of residual stresses/strains during the sample's grinding, heating, and freezing processes. Fourier-transformative infrared spectroscopy confirmed the presence of metal-oxygen bonds in spinel NCFO and Ti-O and Ba-O bonds in perovskite BaTiO3. UV-vis spectra disclose the energy gap values of the magnetoelectric composites. It has been found that the energy gap values for pure ferrite are 1.53 eV, the pure ferroelectric phase is 2.99 eV, and the composites possess the Eg values of 1.78 eV, 2.33 eV, 2.77 eV with decreasing ferrite concentration. The M-H hysteresis loops reveal the ferromagnetic nature of pure ferrite as well as the presence of ferromagnetism in composites. The magnetic moment of the NCFO has been found as 2.26 µB and it further decreased to 0.59 µB for the 0.25NCFO-0.75BTO compound. The magneto crystalline anisotropy has been calculated using the law of approach (LA) method and the details are discussed in the paper. [ABSTRACT FROM AUTHOR]

Mn doping has been used to improve the physical chemistry of lead halide perovskite nanocrystals such as CsPbX3, where X is a halogen ion. In this paper, a two‐phase method for Mn‐doped CsPbX3 nanosheets (where X=Br, Cl), namely water‐hexane system, is reported. Compared to conventional catalyst arrays, the band gap of CsPbBr3 nanocrystalline is easily tuned, the carrier diffusion distance is remote, the band edge position of the band structure is favorable for a wide range of electrocatalytic redox reactions, and the catalytic active site is maximally exposed, providing a larger electrolyte contact area. The porous hierarchical structure also accelerates the release of hydrogen bubbles. The results showed that the optimized Mn : CsPbBr3 catalyst exhibited excellent electrolytic performance of aquatic hydrogen in alkaline electrolyte (1 mol/L KOH). The overpotentials of the oxygen evolution reaction (OER) at the current densities of 10 and 100 mA cm−2 are only 114.4 and 505.4 mV, respectively, with a Tafel slope of 43 mV dec−1. At a current density of 10 mA cm−2, the excess potential required for the hydrogen evolution reaction (HER) is 158.6 mV and it exhibits excellent electrochemical stability. The Mn : CsPbBr3 nanocrystalline consists of two electrodes for hydrolysis of water, requiring only a voltage of 1.45 V. This provides implications for the optimization of electrocatalysts in alkaline electrolytes with the aim of developing next generation 2D electrocatalysts for overall water splitting. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the Bloch bands and develop a linear response theory for nonlinear systems, where the interplay between topological parameters and nonlinearity leads to new band structures. The nonlinear system under consideration is described by the Qi–Wu–Zhang model with Kerr-type nonlinearity, which can be treated as a nonlinear version of Chern insulator. We explore the eigenenergies of the Hamiltonian and discuss its Bloch band structures as well as the condition of gap closing. A cone structure in the ground Bloch band and tubed structure in the excited Bloch band is found. We also numerically calculate the linear response of the nonlinear Chern insulator to external fields, finding that these new band structures break the condition of adiabatic evolution and make the linear response not quantized. This feature of response can be understood by examining the dynamics of the nonlinear system. [ABSTRACT FROM AUTHOR]

Yttrium oxide (Y2O3)$( {{{\mathrm{Y}}}_2{{\mathrm{O}}}_3} )$ has the potential to be used as a host material for creating polycrystalline transparent ceramics (PTCs). This paper presents an experimental study on opto‐electrical properties of Y2O3${{\mathrm{Y}}}_2{{\mathrm{O}}}_3$ using zirconium oxide (ZrO2)$( {{\mathrm{ZrO}}_2} )$ and lanthanum oxide (La2O3)$({\mathrm{La}}_2{{\mathrm{O}}}_3)$ as sintering aids via the co‐precipitation technique. The sintering aids improve the properties, sintering process, and lower the sintering temperature. Five different compositions of Y2O3(((Y1−xZr0.02Lax)2O3),wherex=0,3,6,and9at.%)${{\mathrm{Y}}}_2{{\mathrm{O}}}_3\ ( {({{( {{{\mathrm{Y}}}_{1 - x}{\mathrm{Zr}}_{0.02}{\mathrm{La}}_x} )}}_2{{\mathrm{O}}}_3} ),{\mathrm{\ where\ }}x = 0,\ 3,\ 6,{\mathrm{\ and\ }}9{\mathrm{\ at}}.{\mathrm{\% }})$ were synthesized and they were then used to analyze for their structural, morphological, physio‐chemical, and electrical characteristics. For the system studied, the addition of ZrO2${\mathrm{ZrO}}_2$ and La2O3${\mathrm{La}}_2{{\mathrm{O}}}_3$ does not change the phase of pure Y2O3${{\mathrm{Y}}}_2{{\mathrm{O}}}_3$, but an increase in the crystal and grain size from 31.2$31.2$ to 42.5nm$42.5{\mathrm{\ nm}}$ and 10.2 µm to 16.4 µm was noticed. The thermal characterization over thermogravimetric analysis/differential thermal calorimetry (TGA/DSC) determines the temperature at which pure Y2O3${{\mathrm{Y}}}_2{{\mathrm{O}}}_3$ undergoes a phase transition, specifically over 700°C. A reduction in the band gap due to strain induced by the dopant resulted in a decrease in energy from 5.54$5.54$ to 4.8eV$4.8{\mathrm{\ eV}}$. The dielectric constant of Y2O3${{\mathrm{Y}}}_2{{\mathrm{O}}}_3$ doped with 9at.%La$9{\mathrm{\ at}}.{\mathrm{\% \ La}}$ exhibits a significant increase of ∼50%${\sim}50\%$. [ABSTRACT FROM AUTHOR]

Tin oxide (SnO2) is one of the important semiconductors used in the application of solar cells because of its chemical–mechanical stability and wide band gap. These properties are very important for the performance development and photoanode optimization of a dye‐sensitized solar cell (DSSC). However, the low conduction band value of SnO2 reduces the photovoltaic efficiency, which limits the application of DSSC. Therefore, the doping strategy was used to increase the sensitivity to the visible light spectrum and change the light absorption properties of SnO2. In this paper, pure SnO2, Ag/SnO2, Pt/SnO2, and Pt/Ag/SnO2 nanoparticles were synthesized at the nanoscale by a simple chemical sol–gel method. To characterize the structure, morphological/chemical properties, optical properties, and surface properties of the synthesized SnO2 nanoparticles, X‐Ray Diffraction (XRD), ultraviolet–visible, Brunauer–Emmett–Teller, Scanning Electron Microscopy (SEM)/Energy Dispersive X‐Ray Spectroscopy (EDX), Transmission Electron Microscopy (TEM), and particle size analysis were respectively used. XRD results showed that the crystal sizes varied between 8.8 and 12.2 nm depending on the doping. Doping processes resulted in reductions in particle sizes. Optical studies resulted in decreases in the band gap with the doping process. The conclusions obtained have shown that Ag doping, and Pt–Ag co‐doping can be promising for use as photoanode materials in semiconductor technology and especially in DSSC applications. [ABSTRACT FROM AUTHOR]

The electronic and photocatalytic properties of a type-II ZnS/HfS 2 heterojunction are comprehensively analyzed through first-principles calculations in this paper. By calculating the binding energy and phonon spectrum of five potential stacking patterns, the stable structure of the ZnS/HfS 2 heterojunction is determined. The electronic structure calculations indicate that the heterojunction has a type-II alignment with a 1.26 eV band gap. The heterojunction exhibits high carrier mobilities (4387.36 and 9561.39 cm2V–1S−1 for X and Y directions). The photocatalytic water splitting process of the heterojunction can be explained by the direct Z-scheme mechanism. The built-in electric field enables rapid recombination of electron-hole pairs at CBM and VBM, while the hydrogen evolution reaction and oxygen evolution reaction can separately be achieved at the ZnS layer and HfS 2 layer to complete the overall water splitting. The free energy analysis indicates that the ZnS/HfS 2 heterojunction has high activity for overall water splitting under illumination. Moreover, the calculated solar-to-hydrogen efficiency of the heterojunction reaches 30%, ensuring its photocatalytic performance. Remarkably, the type-II alignment is maintained and the catalytic performance can be further improved under biaxial strain because of the enhanced optical absorption in visible light and the reduced band gap. This work reveals that ZnS/HfS 2 heterojunction is a potentially novel photocatalytic material for efficient overall water splitting. [Display omitted] • Proposed novel type-II ZnS/HfS 2 heterojunction with 1.26 eV band gap. • Achieves overall water splitting via direct Z-scheme mechanism. • High carrier mobility and 30% solar-to-hydrogen efficiency. • Enhanced catalytic performance under biaxial strain. [ABSTRACT FROM AUTHOR]

This paper examines the influence of building characteristics, occupant demographics and behaviour on gas and electricity consumption, differentiating between family groups; homes with children; homes with elderly; and homes without either. Both regression and Lasso regression analyses are used to analyse data from a 2019 UK-based survey of 4358homes (n = 1576 with children, n = 436 with elderly, n = 2330 without either). Three models (building, occupants, behaviour) were tested against electricity and gas consumption for each group. Results indicated that homes without children or elderly consumed the least energy. Property Type emerged as the strongest predictor in the Building Model (except for homes with elderly), while Current Energy Efficiency was less significant, particularly for homes with elderly occupants. Homeownership and number of occupants were the most influential factors in the Occupants Model, though this pattern did not hold for homes with elderly. Many occupant and behaviour variables are often considered 'unregulated energy' in calculations such as SAP and are thus typically disregarded. However, this study found these variables to be significant, especially as national standards improve. The findings suggest that incorporating occupant behaviour into energy modelling could help reduce the energy performance gap. [ABSTRACT FROM AUTHOR]

With the rapid development of flexible displays and wearable electronics, there are a substantial demand for colorless transparent polyimide (CPI) films with different properties. Traditional trial‐and‐error experimental methods are time‐consuming and costly, and density functional theory based prediction of HOMO‐LUMO gap energy also takes time and is prone to varying degrees of error. Inspired by machine learning (ML) applications in molecular and materials science, this paper proposed a data‐driven ML strategy to study the correlation between microscopic molecular mechanisms and macroscopic optical properties. Based on varying degrees of impact of various molecular features on the cutoff wavelength (λcutoff), the ML algorithm is first used to quickly and accurately predict the λcutoff of CPI. Several new CPI films are then designed and prepared based on the key molecular features, and the predicted values of their λcutoff are effectively verified within the experimental error range. The interpretability provided by the model allows to establish correlations between the nine key descriptors identified and their physicochemical meanings. The contributions are also analyzed to the transparency of polyimide films, thereby giving insight into the molecular mechanisms underlying transparency modulation for CPIs. [ABSTRACT FROM AUTHOR]