Structure Of Materials Research Articles

Recent Advancement in Applications of Hybrid Superconductor and Semiconductor Nanomaterials

Abstract: The study of the characteristics of materials with a size range of 1–100 nm is referred to as nanoscience. Nanotechnology deals with manipulating the molecular structure of materials to modify their inherent properties and acquire new properties with novel use. The principles of nanotechnology can be incorporated with superconductivity as well as in semiconductors. Superconductivity is a promising physical property of materials, and it has been an intriguing and stimulating subject of research due to its practical application in several fields. The development of new technologies depends on novel materials. One such material is hybrid superconductor/ semiconductor nanomaterial, which has now been recognized as an exciting material for different applications due to its exceptional physical and chemical properties. There is a report on implementing capable superconductors in induced proximity of a substantial energy difference in semiconductors when strong magnetic fields are present. It is among one of the objectives for applications of superconductor/ semiconductor hybrid nanomaterials in quantum information technologies in the future. These materials have numerous applications in different fields such as photoinduced superconductors, amplifiers, electric grids, SQUID, quantum computing devices, magnetometers, and various smart technologies including electronics, and the energy sector. These superconductor/semiconductor hybrid nanomaterials could be considered as the foundation of next-generation technology. This mini review aims to compile the fabrication techniques and properties of these hybrid nanomaterials and their potential applications as well as promising avenues of future aspects.

Unsupervised deep denoising for four-dimensional scanning transmission electron microscopy

By simultaneously achieving high spatial and angular sampling resolution, four dimensional scanning transmission electron microscopy (4D STEM) is enabling analysis techniques that provide great insight into the atomic structure of materials. Applying these techniques to scientifically and technologically significant beam-sensitive materials remains challenging because the low doses needed to minimise beam damage lead to noisy data. We demonstrate an unsupervised deep learning model that leverages the continuity and coupling between the probe position and the electron scattering distribution to denoise 4D STEM data. By restricting the network complexity it can learn the geometric flow present but not the noise. Through experimental and simulated case studies, we demonstrate that denoising as a preprocessing step enables 4D STEM analysis techniques to succeed at lower doses, broadening the range of materials that can be studied using these powerful structure characterization techniques.

The Role of Methods for Applying Cucurbit[6]uril to Hydroxyapatite for the Morphological Tuning of Its Surface in the Process of Obtaining Composite Materials

In this work, composite materials were obtained for the first time using various methods and the dependences of the resulting surface morphologies were investigated. This involves modifying the surface with cucurbit[n]urils, which are highly promising macrocyclic compounds. The process includes applying cucurbit[6]uril to the hydroxyapatite surface in water using different modification techniques. The first method involved precipitating a dispersion of CB[6] in undissolved form in water. The second method involved using fully dissolved CB[6] in deionized water, after which the composite materials were dried to constant weight. The third method involved several steps: first, CB[6] was dissolved in deionized water, then, upon heating, a dispersion of CB[6] was formed on the surface of HA. The fourth method involved using ultrasonic treatment. All four methods yielded materials with different surface morphologies, which were studied and characterized using techniques such as infrared (IR) spectroscopy and scanning electron microscopy (SEM). Based on these results, it is possible to vary the properties and surface morphology of the obtained materials. Depending on the method of applying CB[6] to the surface and inside the HA scaffold, it is possible to adjust the composition and structure of the target composite materials. The methods for applying CB[6] to the hydroxyapatite surface enhance its versatility and compatibility with the body’s environment, which is crucial for developing new functional composite materials. This includes leveraging supramolecular systems based on the CB[n] family. The obtained results can be used to model the processes of obtaining biocomposite materials, as well as to predict the properties of future materials with biological activity.

Multi-Color Spaceplates in the Visible.

The ultimate miniaturization of any optical system relies on the reduction or removal of free-space gaps between optical elements. Recently, nonlocal flat optic components named "spaceplates" were introduced to effectively compress space for light propagation. However, space compression over the visible spectrum remains beyond the reach of current spaceplate designs due to their inherently limited operating bandwidth and functional inefficiencies in the visible range. Here, we introduce "multi-color" spaceplates performing achromatic space compression at three distinct color channels across the visible spectrum to markedly miniaturize color imaging systems. In this approach, we first design monochromatic spaceplates with high compression factors and high transmission amplitudes at visible wavelengths based on a scalable structure and dielectric materials widely used in the fabrication of meta-optical components. We then show that the dispersion-engineered combination of monochromatic spaceplates with suitably designed transmission responses forms multicolor spaceplates that function achromatically. The proposed multicolor spaceplates, composed of amorphous titanium dioxide and silicon dioxide layers, efficiently replace free-space volumes with compression ratios as high as 4.6, beyond what would be achievable by a continuously broadband spaceplate made of the same materials. Our strategy for designing monochromatic and multicolor spaceplates, along with the presented theoretical and computational results, show that strong space-compression effects can be achieved in the visible range. Our findings may ultimately enable a new generation of ultrathin optical devices for various applications.

Algorithms and software for processing images of the structure of metallic materials for the purpose of determining creep characteristics

The paper contains a description of the approach, algorithms, and software tool for image analysis of deformed material structures. The developed approach is based on the analysis of the microstructure of the material to identify important factors that affect high-temperature deformation during creep in a heat-resistant nickel-based alloy, namely, the dimensions of the channels and their orientation. The developed software tool uses algorithms for converting images into binary black and white using the Otsu method. The intensity of the gradient at each point of the image is visualized using the Sobel operator. Fragment boundaries are determined using the Canny edge detector. Straight line segments are found using the Hough transformation. The software tool is implemented in the Python programming language using the OpenCV library. The main components are described and a flow chart of the program is provided. With the use of the developed software, the transformation of the known experimentally obtained images of the structures of the specimens from heat-resistant nickel-based alloy CMSX-4 deformed at a temperature of 1273K and in a wide range of stresses at different time moments was performed. The results of the analysis of the dimensions of the g-phase channels in the alloy using quantitative evaluation of transformed binary images are discussed. The found characteristics were matched to the value of the creep strain rate, which was determined by calculation based on known experimental data. The possibility of determining the transition from the secondary creep to the stage of avalanche-like growth of strains and hidden damage is shown. For the considered example, the location of the channels in the representative image was determined. A technique for correcting creep curves with the involvement of material structure image processing data is proposed.

Strong Dependence of Point Defect Properties in Metal Halide Perovskites on Description of van der Waals Interaction.

Weaker than ionic and covalent bonding, van der Waals (vdW) interactions can have a significant impact on structure and function of molecules and materials, including stabilities of conformers and phases, chemical reaction pathways, electro-optical response, electron-vibrational dynamics, etc. Metal halide perovskites (MHPs) are widely investigated for their excellent optoelectronic properties, stemming largely from high defect tolerance. Although MHPs are primarily ionic compounds, we demonstrate that vdW interactions contribute ∼5% to the total energy, and that static, dynamics, electronic and optical properties of point defects in MHPs depend significantly on the vdW interaction model used. Focusing on widely studied CsPbBr3 with the common Br vacancy and interstitial defects, we compare the PBE, PBE+D3, PBE+TS, PBE+TS/HI and PBE+MBD-NL models and show that vdW interactions strongly alter the global and local geometric structure, and change the fundamental bandgap, midgap state energies and electron-vibrational coupling. The vdW interaction sensitivity stems from involvement of heavy and highly polarizable chemical elements and the soft MHP structure.

Breaking Surface-Plasmon Excitation Constraint via Surface Spin Waves.

Surface plasmons in two-dimensional (2D) electron systems have attracted great attention for their promising light-matter applications. However, the excitation of a surface plasmon, in particular, transverse-electric (TE) surface plasmon, remains an outstanding challenge due to the difficulty to conserve energy and momentum simultaneously in the normal 2D materials. Here we show that the TE surface plasmons ranging from gigahertz to terahertz regime can be effectively excited and manipulated in a hybrid dielectric, 2D material, and magnet structure. The essential physics is that the surface spin wave supplements an additional freedom of surface plasmon excitation and thus greatly enhances the electric field in the 2D medium. Based on widely used magnetic materials like yttrium iron garnet and manganese difluoride, we further show that the plasmon excitation manifests itself as a measurable dip in the reflection spectrum of the hybrid system while the dip position and the dip depth can be well controlled by an electric gating on the 2D layer and an external magnetic field. Our findings should bridge the fields of low-dimensional physics, plasmonics, and spintronics and open a novel route to integrate plasmonic and spintronic devices.

Computational applications for the discovery of novel antiperovskites and chalcogenide perovskites: a review.

Novel perovskites pertain to newly discovered or less studied variants of the conventional perovskite structure, characterized by distinctive properties and potential for diverse applications such as ferroelectric, optoelectronic, and thermoelectric uses. In recent years, advancements in computational methods have markedly expedited the discovery and design of innovative perovskite materials, leading to numerous pertinent reports. However, there are few reviews that thoroughly elaborate the role of computational methods in studying novel perovskites, particularly for state-of-the-art perovskite categories. This review delves into the computational discovery of novel perovskite materials, with a particular focus on antiperovskites and chalcogenide perovskites. We begin with a discussion on the computational methods applied to evaluate the stability and electronic structure of materials. Next, we highlight how these methods expedite the discovery process, demonstrating how rational simulations contribute to researching novel perovskites with improved performance. Finally, we thoroughly discuss the remaining challenges and future outlooks in this research domain to encourage further investigation. We believe that this review will be highly beneficial both for newcomers to the field and for experienced researchers in computational science who are shifting their focus to novel perovskites.

Numerical simulation of the creep of a turbine blade made of a monocrystalline alloy

The article is devoted to the creep model of a monocrystalline alloy and the development of a methodology for identifying material parameters based on the results of physical experiments. A finite element analysis of the creep of a gas turbine engine blade was performed. Creep is one of the most dangerous types of deformation in the operating conditions of turbine blades. In the process of studying the problems of assessing the strength of turbine blades of aircraft engines and power plants, special attention should be paid to the study of stress redistribution during creep. The characteristics of the crystallographic structures of modern turbine blades have a very significant influence on the progress of the crack development process during engine operation. To date, turbine blades are manufactured by the method of single-crystal casting. This type of blade material structure is characterized by orthotropic mechanical properties. This study considers the steady-state creep model of an anisotropic heat-resistant single-crystal alloy with cubic symmetry. The authors carried out a numerical simulation of the material parameters using the well-known literary creep properties of single crystals. An algorithm is described that allows you to determine some creep characteristics of single crystals. The parameters of the given ratios can be obtained after conducting direct experiments, or based on micromechanical analysis, using the example of composite materials. The authors calculated the creep constants of a typical heat-resistant monocrystalline alloy as a result of the approximation of its creep curves, which were obtained experimentally. Based on the Norton-Bailey equation and using the Maple Release 2021.0 calculation complex, a graph of the dependence of the rate of creep deformation on the level of load applied to the material was plotted, and the minimum rate of deformation and creep constants were also determined. The results of the calculations were used for finite-element simulation of creep on the example of a solid-state model of a high-pressure turbine blade. Several series of calculations were carried out on the basis of the ANSYS Workbench complex, in particular, the calculation of the elastic problem when the blade is loaded by centrifugal forces, as well as the accumulation of creep deformations at different exposure times. Graphs of the change in equivalent stresses and creep deformations as a function of time are plotted.

Ultrasound-assisted extraction of sumac fruit oil and analysis of its fatty acid composition.

The use of ultrasound for enhancing the extraction of sumac fruit oil was investigated to maximize the utilization of available sumac fruit resources. The optimal extraction parameters were determined using single-factor trials and Box-Behnken design optimization and were found to be a liquid-to-material ratio of 13:1mL/g, an ultrasound temperature of 47°C, and an ultrasound duration of 32min. These yielded a 20.59% extraction rate of the oil. The ultrasonic-assisted approach markedly increased the extraction rate and significantly reduced the extraction time when compared to classical Soxhlet extraction. The resulting sumac fruit oil had a brown-yellow color with peroxide, acid, and iodine concentrations of 2.43mg/g, 0.44g/100g, and 135g/100g, respectively, and relative density (d20 20), and refractive index (20°C) values of 0.911, and 1.469, respectively. The primary fatty acids in the oil were stearic, linoleic, palmitic, linolenic, and oleic acids. With a 74.14% unsaturated fatty acid content, it has a high nutritional value as well as significant development and usage potential. PRACTICAL APPLICATION: This study demonstrates a highly efficient method for extracting vegetable oils and fats. It has the advantages of simple operation, low extraction temperature, short extraction time, high extraction rate, no damage to the material structure, excellent phusicai and chemical properties of the extracted vegetable oil, low cost, and the potential application in the food industry is crucial.

A deep equivariant neural network approach for efficient hybrid density functional calculations

Hybrid density functional calculations are essential for accurate description of electronic structure, yet their widespread use is restricted by the substantial computational cost. Here we develop DeepH-hybrid, a deep equivariant neural network method for learning the hybrid-functional Hamiltonian as a function of material structure, which circumvents the time-consuming self-consistent field iterations and enables the study of large-scale materials with hybrid-functional accuracy. Our extensive experiments demonstrate good reliability as well as effective transferability and efficiency of the method. As a notable application, DeepH-hybrid is applied to study large-supercell Moiré-twisted materials, offering the first case study on how the inclusion of exact exchange affects flat bands in magic-angle twisted bilayer graphene. The work generalizes deep-learning electronic structure methods to beyond conventional density functional theory, facilitating the development of deep-learning-based ab initio methods.

Large-Scale Construction and Analysis of Amorphous Porous Polymer Network Materials.

In recent decades, data-driven methodologies have emerged as irreplaceable tools in materials science, particularly for elucidating structure-property relationships and facilitating the discovery of novel materials. However, despite the rapid development witnessed in other domains, amorphous materials have received relatively less attention in this context. The disordered atomic structure of amorphous materials resulting from irreversible reactions between building blocks has posed a difficulty in structural modeling, leading to a lack of databases that accurately reflect the amorphous nature of these materials. In this work, a database composed of 10,237 porous polymer networks (PPNs) was constructed from self-assembly simulations, resulting in the largest database of PPNs considering their amorphous characteristics. Through the distinct differences observed in comparison with existing databases, we emphasize that carefully considering the structural disorder of PPNs is essential for accurately characterizing their chemical behaviors. Machine learning models trained on the constructed database have confirmed that the macroscopic properties of amorphous PPNs can be predicted solely from the atomic structures of their monomers, implying that the characteristics of previously unseen PPNs can be assessed without the need for additional self-assembly simulations.

Electromagnetic Interference Shielding Films: Structure Design and Prospects.

The popularity of portable and wearable flexible electronic devices, coupled with the rapid advancements in military field, requires electromagnetic interference (EMI) shielding materials with lightweight, thin, and flexible characteristics, which are incomparable for traditional EMI shielding materials. The film materials can fulfill the above requirements, making them among the most promising EMI shielding materials for next-generation electronic devices. Meticulously controlling structure of composite film materials while optimizing the electromagnetic parameters of the constructed components can effectively dissipate and transform electromagnetic wave energy. Herein, the review systematically outlines high-performance EMI shielding composite films through structural design strategies, including homogeneous structure, layered structure, and porous structure. The attenuation mechanism of EMI shielding materials and the evaluation (Schelkunoff theory and calculation theory) of EMI shielding performance are introduced in detail. Moreover, the effect of structure attributes and electromagnetic properties of composite films on the EMI shielding performance is analyzed, while summarizing design criteria and elucidating the relevant EMI shielding mechanism. Finally, the future challenges and potential application prospects of EMI shielding composite films are prospected. This review provides crucial guidance for the construction of advanced EMI shielding films tailored for highly customized and personalized electronic devices in the future.

Direct recycling of anode active material from Li-ion batteries using TiNb2O7 anode

As the demand for large lithium-ion batteries (LIBs) for automotive and other applications rapidly grows, recycling of electrode materials has become essential owing to the large amount of waste material generated by battery manufacturing (e.g., battery scrap) and end-of-life (EOL) batteries. While there have been many studies on recycling of cathode materials, we propose a direct recycling process for anode material using TiNb2O7 (TNO) as the active material, as it offers high capacity and long life. Calcination was introduced to separate the anode active material from the current-collecting foil, and a regeneration method was investigated for TNO anodes from scrap and EOL battery waste. After calcination, the active material can be easily separated from the aluminum current-collecting foil owing to the binder disappearing. The structure of the active material was investigated using X-ray diffraction and scanning electron microscopy. TNO active material recycled from scrap and EOL was found to maintain the structure of virgin material. A cell was fabricated using recycled TNO and cell performance was evaluated. The cell capacity and rate capacity were found to be almost equivalent to those of virgin material. In terms of the carbon footprints of products (CFP), CO2 emissions during the recycling process were compared between recycled material and virgin material, and it was found that CO2 emissions were reduced to 0.7-CO2eq/kg for scrap material and 3.8-CO2eq/kg for EOL waste material, compared with 4.8-CO2eq/kg for virgin material. Thus, the feasibility of low CO2 emissions during TNO anode direct recycling was confirmed in principle. A simple and low CO2 emission recycling loop can thus be constructed by employing a stable TNO active material structure and direct-recycling process with calcination.

First-principles study on impact of Mo doping on the formation enthalpy and electronic structure of Li2MgN2H2 material

The influence of Mo doping on the formation enthalpy and electronic structure of Li2MgN2H2 material, as well as the specific improvement mechanism of its hydrogen storage properties, were investigated by employing the first-principles calculation method. The calculation results exhibit that when Mo is doped into the Li2MgN2H2 material, it is more inclined to take up Mg lattice site at the 8c position. For the Li2MgN2H2 material, Mo doping can effectively reduce its formation enthalpy by ca. 91.16 kJ/mol, thus resulting in the reduction of its structural stability. Moreover, when the Li2MgN2H2 material is doped with Mo, its cell volume increases, and its band gap narrows obviously. Meanwhile, the strong force between Mo and N causes the bond strengths of N–H and Li–N to weaken significantly. The aforementioned factors are beneficial to the improvement of its hydrogen sorption kinetics. This work aims to provide theoretical guidance for further development of new efficient catalysts to promote the Li–Mg–N–H material's application.

In Situ Stimulus Response Study on the Acetylene/Ethylene Purification Process in MOFs.

Efficient removal of acetylene (C2H2) impurities from polymer-grade ethylene (C2H4) in a simple, clean manner remains a challenging goal in industry. The use of porous materials such as metal-organic frameworks (MOFs) is promising for this aim but the acquisition of high purification performance is still hindered by few knowledge on the purification process because the previous conclusions were derived basically from the non-breakthrough tests or ignored the influence of structural difference (crystal structure, morphology, or defect). Here we propose an unprecedented in situ stimulus response strategy to minimize the influence of structural difference, obtain the gas-loading crystal structures of the same MOF before and after light or heat stimulation, directly observe the evolution of pore charge distribution and pore×××gas interactions under light/heat induction, and finally summarizes the favorable structure for highly efficient purification of C2H4. This study opens a new route to understand the relationship between the structure and separation performance for porous materials.

Effects of chemical etching on surface structure and tribological behavior of silicate substrates

Abstract This study investigated the effect of chemical etching on the surface structure and tribological behavior of silicate substrates. Silicate surfaces were etched using a mixture of nitric acid (HNO3) and ammonium bifluoride (NH4HF2) for durations ranging from 1 to 60 min. The etched surfaces were characterized using optical microscopy, scanning electron microscopy, surface profilometry, water contact angle measurements, and UV–vis spectroscopy to evaluate the changes in surface morphology, roughness, wettability, and optical properties. Tribological performance was assessed using reciprocating ball-on-plate friction tests. The results showed that increasing the etching time resulted in the formation of microscale surface features, increased surface roughness, enhanced hydrophilicity, and reduced optical transmittance. The average friction coefficient decreased with an increase in the etching time up to 30 min, beyond which a slight increase was observed. The 1-minute etched specimen exhibited the best wear resistance with the narrowest wear track and the least material removal. The improved tribological performance was attributed to the formation of a stable transfer film, reduced real contact area, and entrapment of wear debris. This study highlights the potential of chemical etching as a technique to tailor the surface structure and tribological properties of silicate materials for various applications.

In Situ Stimulus Response Study on the Acetylene/Ethylene Purification Process in MOFs

Efficient removal of acetylene (C2H2) impurities from polymer‐grade ethylene (C2H4) in a simple, clean manner remains a challenging goal in industry. The use of porous materials such as metal–organic frameworks (MOFs) is promising for this aim but the acquisition of high purification performance is still hindered by few knowledge on the purification process because the previous conclusions were derived basically from the non‐breakthrough tests or ignored the influence of structural difference (crystal structure, morphology, or defect). Here we propose an unprecedented in situ stimulus response strategy to minimize the influence of structural difference, obtain the gas‐loading crystal structures of the same MOF before and after light or heat stimulation, directly observe the evolution of pore charge distribution and pore×××gas interactions under light/heat induction, and finally summarizes the favorable structure for highly efficient purification of C2H4. This study opens a new route to understand the relationship between the structure and separation performance for porous materials.

Physical Properties of Selected Fruit Fibre and Pomace in the Context of Their Sustainable Use for Food Applications

Pomace, a waste product, generates a huge problem in the fruit and vegetable industry. Numerous studies prove that pomace and fibre are valuable sources of many nutrients. Due to their properties, their popularity is growing in many industries. Water vapour isotherms and kinetics were determined for selected fruit fibre and pomace. The activity and water content, colour, apparent and bulk density, and material structure were also investigated. In addition, the thermal stability of the tested fibres and pomace was examined. Fibre and pomace from chokeberries, apples and currants were used in the research. The determined kinetic curves proved that apple fibre absorbed more water vapour. The isotherms were found to have a shape characteristic of type III sorption isotherms. The Guggenheim–Anderson–de Boer model (GAB) described experimental data for sorption isotherms well (taking an RMS value of less than 10% as a good fit of the model to the sorption data). Thermogravimetric analysis showed good thermal stability, and all analysed fruit fibre and pomace showed similar behaviour in the three main stages of weight loss. The results suggest that the analysed waste materials can be used for different applications, including flour replacements for food products or filling materials in edible packaging films.

Chemical characteristics of Salix psammophila sand barriers are accelerated degradation by ultraviolet irradiation and water.

The implementation of Salix psammophila sand barriers measures constitutes a crucial element in desertification control, providing a solid theoretical foundation for the future application and pretreatment of sand barriers in production practices. To address the specific damage types predominant in desert environments, we executed simulations of ultraviolet irradiation and rainfall phenomena on mechanical sand barriers in sandy areas and also inspected the variations in chemical properties during accelerated aging processes. The findings unequivocally demonstrate that: (1) The synergistic impact of ultraviolet irradiation and water accelerated the deformation and fracturing of the S.psammophila sand barriers, thereby causing a partial degradation of its chemical properties and conspicuous lignin oxidation; (2) The fissure of the sand barrier deepened, resulting in structural alterations. The existence of water expedites the degradation process of S.psammophila sand barriers under ultraviolet irradiation. (3)With respect to the binding form of C atoms, the carbon atoms at S.psammophila sand barriers were highly oxidized after 576 hours of accelerated aging. The components of C2 (C-O) and C3 (C=O) rising to 40.16% and 12.24% respectively, while the components of C1 (C-C) declined to 47.60%. The amount of hydroxyl (O-C-O), carbonyl (C=O), and carboxyl (O-C=O) groups increases in line with the expansion of the contact area between the sand barrier structure and ultraviolet irradiation as well as water. More free radical substances are generated, thereby causing the chemical binding properties to tend to be more stable. In summary, Ultraviolet irradiation and water change are the primary factors influencing the degradation of S.psammophila sand barriers material structure and properties. In future desertification control, it is imperative to focus on enhancing the longevity of sand barriers by ensuring their waterproofing capabilities and resistance to ultraviolet irradiation.