Search

This study reports a modified Haldane model that supports transitions between valley and Chern topological phases in photonic crystals. Berry curvatures of this system can be flexibly diffused, converged, or flipped by endowing different model parameters, thus exhibiting exotic topological interface/edge behaviors, such as topological bound states with ideally zero dispersion. Importantly, the coexistence of chiral and antichiral edge states preserved simultaneously by valley and Chern topological phases is achieved by splicing together two kinds of topological structures as an entirety. It further employs a honeycomb lattice comprising gyromagnetic and ceramic cylinders at microwave frequencies, where inversion and time‐reversal symmetries can be flexibly manipulated. Topological interface transport is demonstrated, including two opposite signs of group velocities jointly protected by topologically distinct regimes. These results bridge the gap between valley and Chern topological physics and shed light on developing reconfigurable integrated device applications for classical (quantum) information processing and photonic computing. [ABSTRACT FROM AUTHOR]

Higher‐order topological insulators hosting topological modes at hinges and corners provide a new avenue for disorder‐immune light transport, which prospects great potential in applications of integrated photonics devices. However, the active control of topological modes in 3D higher‐order topological insulators is not realized yet, and its construction is too complicated and huge to analyze. Here, a method is proposed to construct effective Hamiltonians for higher‐order topological insulators, which provides a correct physical picture of the states and the corresponding energies at the domain walls. A non‐Hermitian 3D honeycomb lattice is constructed, which can generate arbitrary‐located, arbitrary‐shaped, and robust topological hinge states propagating at gain‐loss domain walls. The 3D honeycomb lattice can also appear as non‐Hermitian third‐order TIs exhibiting corner states, which can be dynamically controlled and show new topologically protected confinement rules. This work expands the understanding of the topological properties in non‐Hermitian systems and enables the dynamic control of topological states of different dimensions. [ABSTRACT FROM AUTHOR]

In this work, the effects of doping with carbon (C) and silicon (Si) on the electronic and magnetic properties of phosphorus nitride (PN) monolayer are investigated. PN monolayer is stable, exhibiting the semiconductor nature with indirect band gap of 1.81(2.89) eV calculated by standard Perdew–Burke–Ernzerhof (hybrid HSE06) functional. C and Si impurities prefer doping at N and P sublattices, respectively. PN monolayer is slightly magnetized by doping with 25% of C with total magnetic moment of 0.20 μB$\mu _{\text{B}}$. The magnetization is stronger in the remaining cases with total magnetic moments of 1.00 μB$\mu _{\text{B}}$. Magnetic properties are produced mainly by C and Si impurities. In addition, C and Si codoping is also investigated, in which the magnetization depends strongly on the interatomic distance between impurities. Specifically, the inter‐dopant interactions preserve the non‐magnetic nature of PN monolayer, but significantly reduce the energy gap. However, further separating these dopants leads to the emergence of magnetism with total magnetic moment of up to 1.97 μB$\mu _{\text{B}}$. Results may introduce doping‐based effective method to induce feature‐rich electronic and magnetic properties in buckled honeycomb PN monolayer. Such that, the C‐ and Si‐doped PN sheets are recommended for spintronic applications considering their magnetic semiconductor nature. [ABSTRACT FROM AUTHOR]

Because of the significant effect of geometry on the mechanical properties of auxetic structures, this work focuses on enhancing the re‐entrant hexagonal honeycomb properties, as an auxetic cellular structure with widespread use, by modifying its unit cell's geometry. Herein, six novel structures with additional struts added as supports to the structure are designed to improve the specific energy absorption capacity and flexural modulus. The results reveal that adding supports significantly increases the maximum force tolerated by the structure in the same undergone displacement as the conventional re‐entrant. Furthermore, the findings indicate that honeycombs with concave curved supports outperform conventional re‐entrant honeycombs, showing a significant enhancement in flexural modulus (Ef) by ≈282%, energy absorption, and specific energy absorption by over 297%. Moreover, angle support structures demonstrate outstanding outcomes compared to simple straight supports and single‐support structures. Additionally, a parametric study is carried out using the validated finite‐element model to analyze the influence of the supports' thickness and radius as well as the distance between the middle of the unit cell and the support (L3) in honeycombs with concave curved supports and the β angle of angle supports in the double‐angle support structures. [ABSTRACT FROM AUTHOR]

Negative Poisson's ratio as the anomalous characteristic generally exists in artificial architectures, such as re‐entrant and honeycomb structures. The structures with negative Poisson's ratio have attracted intensive attention due to their unique auxetic effect and many promising applications in shear‐resistant and energy absorption fields. However, experimental observation of negative Poisson's ratio in natural materials barely happens, although various 2D layered materials are predicted in theory. Herein, the anisotropic Raman response and the intrinsic intralayer negative Poisson's ratio of 2D natural black arsenic (b‐As) via strain engineering strategy are reported. The results are evident by the detailed Raman spectrum of b‐As under uniaxial strain together with density functional theory calculations. It is found that b‐As is softer along the armchair than zigzag direction. The anisotropic mechanical features and van der Waals interactions play essential roles in strain‐dependent Raman shifts and negative Poisson's ratio in the natural b‐As along zigzag direction. This work may shed a light on the mechanical properties and potential applications of 2D puckered materials. [ABSTRACT FROM AUTHOR]

In this research, free curling property of the over‐expanded honeycomb (OH) with zero Poisson's ratio was utilized to design and manufacture curved carbon fiber‐reinforced composite (CFRC) sandwich beams by hot compression molding technique and co‐curing process. Three‐point bending experiments were conducted to reveal the failure mechanism of these OH‐based curved sandwich beams with various curvatures. The results reveal that in this research no matter what the curvature is, the shearing fracture of the OH core controls the initial failure of the curved structure, which is followed by upper skin fracture, lower skin delamination and fracture. With the increase of curvature, the ultimate bearing capacity and flexural rigidity of the curved beams will increase. No debonding was observed in the experiments. Highlights: Curved sandwich beams with zero‐Poisson's ratio honeycomb‐core was designed.Deformation process from arc, flattening to anti‐arc was revealed by testing.Strength of curved sandwich beams depends on shear strength of the honeycomb.Beams with smaller curvature have greater bearing capacity and stiffness. [ABSTRACT FROM AUTHOR]

In most of the automobile and aerospace materials, cellular structures are extensively used due to their lightweight and high energy absorption capabilities. Naturally available animal bones and plant stems are light in weight due to their natural cellular structures. This may inspire various researchers for integrating the various lattice structures such as beam, planar, triply periodic minimal surfaces, and voronoi structures on the various structural materials. The development of lattice structures using 3D printing technology has opened up major attention towards fabricating lightweight components without any complications. In this study, the detailed crashworthiness responses such as compressive strength was optimized in terms of varying the topology‐related factors on the carbon fiber reinforced polyethylene terephthalate glycol (CF/PETG) composite. The experimentation was conducted concerning variable topology factors such as shell thickness, unit cell type, wall thickness (WT), unit cell orientation (UCO), skewing angle, and unit cell size. The model was examined and optimized by means of the Taguchi optimization technique. The crashworthiness response was analyzed using the compression test and moreover, this experimental response is used for the optimization processes. From the observation, the topology factors which contributed more for the higher compressive strength will be UCO of 65.47% and WT of 15.20%. Results of the regression study show that the R square value with concern to the compressive strength will be 92.74%. The optimized design parametric condition for CF/PETG composite established a higher compressive strength of 41.179 MPa, From the overall results, it is clear that the variation in the topology factors has developed a huge and favorable impact on the mechanical characteristics of the lattice‐structured CF/PETG polymer composite. Highlights: Hexagonal Lattice structure incorporation on the carbon fiber reinforced PETG composite.Design optimization on the compressive properties.Taguchi optimization is performed on design‐based lattice structures.Unit cell orientation has higher percentage contribution on compressive strength. [ABSTRACT FROM AUTHOR]

With the advent of additive manufacturing, lattice structures have been of increasing interest for engineering applications involving light‐weighting and energy absorption. Several studies have investigated mechanical properties of various lattices made up of mostly unreinforced polymers and lack numerical analysis for reinforced lattice structures. In this paper, mechanical response of short fiber reinforced lattice structures under compression is investigated through experiments and numerical simulations. Three different 2D lattices namely, square grid, honeycomb, and isogrid along with their rotated counterparts were fabricated using 15% wt carbon fiber‐acrylonitrile butadiene styrene and experimentally evaluated through uniaxial compression testing up to 30% strain. As simulations on fiber‐reinforced lattices under large compressive strains are rarely performed and published, finite element models accounting for fiber orientation induced anisotropic mechanical properties and geometrical imperfections were developed to predict the stress–strain characteristics up to 30% compressive strains. The stress–strain curves predicted from the numerical simulations matches well with the experimental responses for various lattice geometries. Various failure mechanisms such as thin strut buckling, contact within the lattice, and fracture of struts under large deformation were investigated. Analyzing energy absorption characteristics of these lattices revealed that the honeycomb structures in horizontal configuration exhibits superior energy absorption capability. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (h‐BN) is an extensively investigated 2D material with exceptional quantum effects, which renders it promising for use in next‐generation nanoelectronic devices. However, the synthesis of single‐ or few‐layer h‐BN nanosheets with large‐area single‐crystal structures is extremely challenging. In this article, a new method is presented for synthesizing h‐BN on a Cu substrate via magnetron sputtering and heat annealing. Three samples with different radio‐frequency (RF) power levels are prepared to evaluate the effect of RF power on h‐BN nanosheet synthesis. Under a higher RF power, the B‐to‐N bonding ratio is closer to 1:1 and further reduces the full width at half maximum of X‐Ray photoelectron spectroscopy B1s and N1s narrow spectra. Heating at 1000 °C reveals white domains with 60° facets, which may correspond to the hexagonal honeycomb lattice structure of h‐BN. Cross‐sectional observations show that a layered structure comprising 10–20 layers forms along the Cu interface. The elemental composition ratio and bonding states reveal the presence of equal amounts of N and B as well as a single peak derived from the B–N bond. Meanwhile, the E2g mode of h‐BN's six‐membered ring structure is indicated at 1364.6 cm−1, thus demonstrating the successful synthesis of an h‐BN film. [ABSTRACT FROM AUTHOR]

The ultra‐alkaline conditions of a hydroflux offer the possibility of redox chemistry far from the electrochemical standard potentials. We explored the possibilities of synthesizing tellurium(VI) compounds, using both tellurium(VI) and tellurium(IV) as starting materials. Colorless, block‐shaped crystals of the oxohydroxotellurate(VI) K2[TeO2(OH)4] were synthesized from (NH4)2TeO4 in a KOH hydroflux at 200 °C. In the triclinic crystal structure, [TeO2(OH)4]2− octahedra are connected via hydrogen bonds to form layers, which are separated from each other by potassium cations. Yellow‐colored platelets of the ferrate(III) tellurate(VI) K2[Fe2TeO6(OH)2] ⋅ 2H2O were obtained by oxidation of TeO2 with H2O2 followed by reaction with Fe(NO3)3 ⋅ 9H2O in a KOH hydroflux. In the monoclinic crystal structure, strongly corrugated anionic layers ∞2[ ${{}_{\infty }{}^{2}[}$ Fe2TeO6(OH)2]2− are covered with water molecules and separated from each other by potassium cations. The octahedrally coordinated iron(III) atoms form a distorted honeycomb network, in which they are antiferromagnetically coupled at room temperature and in external fields up to at least 7 T. [ABSTRACT FROM AUTHOR]

This article presents an effective test method for evaluating the shear performance of repaired honeycomb sandwich panels consisting of glass fiber/epoxy matrix skin and Nomex honeycomb core. Addressing the insufficient research on the shear performance of honeycomb sandwich panels after repair in existing literature, this study conducted mechanical performance tests on the honeycomb sandwich panels before and after repair using the picture frame test method. Surface strain measurements are obtained using digital image correlation (DIC) techniques, and load–displacement and shear stress–strain curves are generated from the experimental results. The study concludes that the repair method utilized in this investigation is effective in restoring the mechanical properties of the sandwich panels. In addition, finite element models of the honeycomb sandwich panels before and after repair are established, and a comparative analysis is conducted between the experimental and simulation results. The study examines the shear modulus, ultimate load, and failure mode of the repaired and unrepaired specimens. The findings verify the feasibility of the picture frame test method for evaluating the shear performance of honeycomb sandwich panels. This study provides valuable insights into the design of shear performance repair for honeycomb sandwich panels and offers theoretical support for material recycling. [ABSTRACT FROM AUTHOR]

Two‐ and three‐periodic vertex‐transitive (isogonal) piecewise‐linear embeddings of self‐entangled and interwoven honeycomb nets are described. The infinite families with trigonal symmetry and edge transitivity (isotoxal) are particularly interesting as they have the Borromean property that no two nets are directly linked. These also lead directly to infinite families of interpenetrating primitive cubic nets (pcu) that are also vertex‐ and edge‐transitive and have embeddings with 90° angles between edges. [ABSTRACT FROM AUTHOR]

Tolerance‐free assembly of modular concrete structures – optimization of module arrangement with metaheuristics Modular structures require dimensional stable components, since large process‐ or material‐related dimensional deviations in individual modules prevent assembly to the overall structure. The article presents a method for optimal placement based on metaheuristics. It helps to avoid cost‐intensive rework. The concept is applied to honeycomb structures in which the individual modules are swapped by permutation. With the so‐called Tabu Search and Simulated Annealing, two solving techniques are methodically used. For this purpose, the maximum nodal deviations of the assembled modules are determined with direct kinematics and compared with the admissible nominal hole clearance of bolted joints in order to assess the assembly capability of the modules. Tolerances from the shrinkage of the concrete on the one hand and those from the production steps of fabrication on the other hand are taken into account. Compared to a random arrangement of the modules, the reduction of maximum nodal deviations of 9 mm to the normalized nominal hole clearance of 3 mm succeeds with the help of the metaheuristics. Honeycomb structures with a width of approx. 7 m and a height of up to 45 m, which are particularly sensitive in terms of assembly, thus no longer require any reworking. Tabu Search proves to be the significantly more efficient solution algorithm, with six times less computation time and up to 24 % fewer deviations to be compensated. An example shows the practical application. [ABSTRACT FROM AUTHOR]

Parameter values extending over multiple temperatures/columns were assumed to have the same value for all the temperatures in question. A smaller quadrupole doublet component, with a relative spectral area fraction being below 3.5%, can be identified as high-spin Fe SP 3+ sp with parameters of I i ( I T i = 60 K) 0.52 mm s SP -1 sp and I E i SB Q sb ( I T i = 60 K) 0.62 mm s SP -1 sp (Table S3), which was presumably formed via low-level oxidation of the sample during its handling. [Extracted from the article]

In this work, the effects of point defects on the electronic and magnetic properties of PAs monolayer are investigated. PAs monolayer is stable in a buckled hexagonal structure, exhibiting indirect gap semiconductor character and is metallized under the presence of vacancies due to the dangling bonds around defect sites. Meanwhile, the non‐magnetic semiconductor character is preserved upon creating antisite defects with a negligible variation of the band gap. Significant magnetism as well as feature‐rich electronic properties are induced by p‐ and n‐type defects. Specifically, doping with Si and Ge atoms leads to the emergence of the magnetic semiconductor nature. In these cases, the total magnetic moment of 1 μB${\mu}_{\text{B}}$ is obtained, where dopant atoms are mainly responsible for the magnetization. Besides, doping with Br induce the half‐metallic nature with a total magnetic moment of 2 μB${\mu}_{\text{B}}$, where magnetic properties are produced by the dopant and its neighbor due to the strong p--p$p\text{--}p$ hybridization. In contrast, weak hybridization is the main reason for the absence of magnetism in the Cl‐doped PAs monolayer. Results presented herein introduce the creation of point defects in buckled semiconductor PAs monolayer as efficient functionalization approaches for optoelectronic and spintronic applications. [ABSTRACT FROM AUTHOR]

Reverse osmosis desalination is a common technique to obtain fresh water from saltwater. Conventional membranes suffer from a trade‐off between salt rejection and water permeability, raising a need for developing new classes of membranes. C‐based membranes with porous graphene and carbon nanotubes offer high salt rejection, water permeability, and fouling resistance. However, controlling the pore size of these membranes is challenging. Therefore, a carbon honeycomb membrane is studied using classical molecular dynamics simulations. It is reported that functionalization with −COO– groups provides 100% salt rejection with around 1000 times higher water permeability than conventional polyamide membranes. Atomic‐level understanding of the effect of the functional groups' location on salt rejection and water permeability is developed. [ABSTRACT FROM AUTHOR]

Graphene is a 2D honeycomb lattice consisting of a single layer of carbon atoms. Graphene has become one of the most preferred materials for sensor development due to its exceptional electrical, mechanical, and thermal characteristics. Nonetheless, little consideration is given to the production and use of crumpled graphene. Specifically, the crumpled graphene structure is a good choice for enhancing sensors' sensitivity and structural deformability by reducing interfacial stress, avoiding electrical failure, and enhancing surface areas. This review article provides an overview of various synthesis processes using crumpled graphene and specifies a brief idea to control crumpled formation in graphene structure for sensing applications in recent years. Furthermore, it summarizes the problems encountered in previously published research articles during the fabrication and performance of sensors with a brief discussion of fundamental mechanics and topological aspects concerning crumpling patterns with sensing performance. It also highlights the current status of crumpling techniques and their effects on developing different sensors using existing crumpling methods, controlled crumpling designs, and sensing methodologies for future applications. [ABSTRACT FROM AUTHOR]

2D SiN honeycomb monolayer structures predicted theoretically have been the focus of interest in materials science for a long time, most recently for their semiconducting and ferromagnetic properties. Herein, by investigating metal‐organic chemical vapor deposition processes and direct heat treatment of epitaxial graphene in ammonia flow, the possibility of realizing a certain periodic 2D structure via Si─N bonds under epitaxial graphene on SiC (0001) is reported. The result is of interest because it is compatible with semiconductor material deposition technologies and future use in nanoscience and nanotechnology. [ABSTRACT FROM AUTHOR]

To enhance the load‐bearing capacity and energy absorption capacity of the honeycomb, three kinds of star‐rhombus honeycombs (SRHs) are proposed by adding rhombic parts to the traditional star‐shaped honeycomb (TSH). The quasi‐static crushing responses of SRHs, including deformation mechanism, crushing stress, specific energy absorption (SEA), and Poisson's ratio, are studied based on the finite‐element (FE) method. The introduction of rhombic parts increases the number of plastic hinges, resulting in significantly higher crushing stress and SEA of the SRHs than that of the TSH. Among the SRHs, SRH‐A has the largest energy absorption, and the SEA value of SRH‐A is 98.2% higher than TSH. Then, parametric studies including wall thickness, cell wall angle, and spacing length between the vertices of the star‐shaped part and the rhombic part are carried out. The wall thickness and cell wall angle have the greatest influence on the crushing response of SRHs. Crushing stress and Poisson's ratio of SRHs can be adjusted by changing the wall thickness of the rhombic part. The configurations and geometric parameters of the rhombic part determine the Poisson's ratio of SRHs. This study provides effective guidance for designing star‐shaped honeycombs with enhanced load‐bearing capacity and energy absorption capacity. [ABSTRACT FROM AUTHOR]

The in‐plane crushing behaviors of hierarchical hexagonal honeycombs, structured by replacing every three‐wall vertex of both the conventional and reentrant hexagonal honeycombs with a small hollow‐circle, are investigated herein. The finite element (FE) models are first verified by an empirical formula from the literature and then further used to simulate the in‐plane crushing behaviors of the honeycombs under different compressive velocities. The deformation mode, plateau stress, and specific energy absorption (SEA) are studied based on the FE simulations. With respect to the conventional hierarchical honeycombs, the reentrant hierarchical honeycombs, in most instances, are found to exhibit higher plateau stress but lower SEA. It is remarkable that the hierarchical hexagonal honeycombs exhibit higher plateau stress and SEA than the basic hexagonal ones, which indicates that the hierarchical design is effective in improving both the impact resistance and energy absorption capabilities of the honeycombs. [ABSTRACT FROM AUTHOR]

BACKGROUND: Heavy oil has the characteristics of high viscosity and low American Petroleum Institute gravity, which makes it difficult to transport and produce. The key to efficiently utilizing heavy oil is reducing viscosity and improving quality. Hydroconversion has the advantages of viscosity reduction and decreased coke production, but it is difficult to separate nonmagnetic catalysts from the reaction system, which affects the industrial application. RESULTS: A spherical Fe3O4 (74.71 emu g−1) and a chain FeFe2O3 (110 emu g−1) were prepared as magnetic cores, and coated with SiO2 and Al2O3 layers, respectively. The metal‐supported catalyst modified with Co and Ni show irregular and honeycomb‐shaped surfaces, and the magnetic saturation strength decreases to 24.91 and 14.63 emu g−1, but still possessing superparamagnetic properties, enabling the catalysts to be separated from the reaction mixture. Fe‐Fe2O3@SiO2@Al2O3@CoNi catalyst has the best viscosity reduction effect for Canadian oil sands asphalt residue at about 410 °C and 10 MPa hydrogen pressure. The viscosity of the liquid product decreased significantly from 56 600 to 135 mPa s at 50 °C, with a viscosity reduction of 99.8%. CONCLUSION: Magnetic catalyst prepared from chain‐like Fe‐Fe2O3 has an excellent honeycomb structure, which can provide increased active surfaces and exhibit improved viscosity reduction performance. This work provides a strategy for the recovery of heavy oil hydrogenation catalysts and is expected to play a key role in the practical application of heavy oil hydrogenation catalytic viscosity reduction. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The properly chosen light management strategy in perovskite solar cell devices is indispensable in achieving high power conversion efficiency. To diminish the reflection losses, texturization of the front surface, similar to what is used in established solar cell technologies, shall be taken into consideration. Within this paper, a honeycomb‐like textured SU‐8 photoresist layer is applied using a roller nanoimprint technique onto a planar perovskite solar cell to minimize reflection losses. The results show that the applied honeycomb pattern reduces the solar‐weighted reflectance from 13.6% to 2.7%, which enhances the current density of the unmodified cell by 2.1 mA cm−2, outperforming the commonly used planar MgF2 antireflective coating by 0.5 mA cm−2. The experimental results are combined with optical modeling to find optimized structures and predict the optical behavior within a solar module. The process used within this work can be transferred to perovskite‐silicon tandem solar cells, providing a promising pathway for the reflection reduction in future devices. [ABSTRACT FROM AUTHOR]

Black absorber with wide‐angle high absorption properties is of great significance to the in‐orbit operation of space optical system. However, up to now, black absorber used in space optical system with wide‐angle high absorption properties has rarely been reported. Herein, this work reports a multiscale structure coordinated black poly(ether ether ketone) (PEEK)‐based black absorber with lightweight, low volatilization, and wide‐angle high absorption properties through 3D printing method. The as‐prepared absorber with honeycomb structure shows a high surface absorptivity (about 96.89%), and excellent wide‐angle high absorption properties which absorptivity attenuation rate is only 1.43% at 70°, benefiting from 3D‐printed honeycomb structure and multi‐scale light trap structure on the absorber inner surface. Besides, high and low temperature cycling test shows that its wide‐angle high absorption properties have a good stability at the space extreme environment, and its collected volatile condensable material (CVCM) is as low as 0.00%. This work provides a new strategy for simple fabrication method of novel lightweight multifunctional‐structure integrated absorber for space optical system. [ABSTRACT FROM AUTHOR]

Modern aerostructures, including wings and fuselages, increasingly feature sandwich structures due to their high‐energy absorption, low weight, and high flexural stiffness. The face sheet of these sandwich structures are typically thin composite laminates with interior honeycombs made of Nomex or aluminum. Standard cores are structurally efficient, but their design cannot be varied throughout the structure. With additive manufacturing (AM) technology, these core geometries can be altered to meet the design requirements that are not met in standard honeycomb cores. This study used a modified aluminum honeycomb core, with increased surface area on the top and bottom, as the core material in sandwich panels. The modified honeycomb core was produced through the laser powder bed fusion method. The behavior of the modified sandwich composite panels was evaluated through three‐point bend, edgewise compression, and impact tests, and their performance was compared to that of a conventional honeycomb core sandwich panel. The three‐point bend test results indicated that the sandwich structure's ultimate shear strength improved by 12.6% with the modified honeycomb core. Additionally, the displacement at the failure of the structure increased by 11%. The edgewise compression tests showed that the ultimate edgewise compressive strength improved by 19.1% when using the modified core. The impact test results revealed that the peak force increased by 8% and the energy‐absorbing capacity of the sandwich structure increased by 20% with the use of the modified honeycomb core. [ABSTRACT FROM AUTHOR]

Cellular hexagonal (conventional) and re‐entrant (auxetic) honeycombs are applicable in automotive, construction, and protective engineering. Auxetic structures own excellent energy absorption and flexural behavior due to their special deformation under loading. This work explores the performance of additively manufactured polylactic acid (PLA)‐ and thermoplastic polyurethane (TPU)‐based hexagonal and re‐entrant honeycombs under flexural loading via experimental three‐point bending (TPB) tests and finite‐element analysis (FEA). 3D‐printed conventional and auxetic cellular structures are filled with polyurethane (PU) foam and their energy absorption capacity and flexural modulus are compared with hollow structures. The results reveal that TPU‐based structures' energy absorption capacity and flexural modulus improve significantly, whereas the PLA‐based structures' performance deteriorates when filled with PU foam. Moreover, re‐entrant honeycombs are better reinforced with foam in comparison to the hexagonal honeycombs, as the re‐entrant's unit cell is more spacious than the hexagonal unit cell. Finally, parametric studies are performed via FEA to investigate the influence of geometric parameters of structures and flexural loading setup on the performance of the honeycombs, showing that structures with thicker struts and higher cell angle can act stiffer under TPB. The outcomes of this research indicate the promising performance of foam‐filled TPU‐based auxetic structures. [ABSTRACT FROM AUTHOR]

Pyrolysis is one of the most common, sustainable, and excellent environmental‐friendly method to evaluate the bio‐energy potential of different types of biomass wastes. Pomegranate peel is a well‐known low‐cost industrial waste. Thus, pomegranate peel's physicochemical properties were explored in detail, and a pyrolysis kinetic study and thermal behavior analysis were performed. Thermal degradation of biomass was investigated on different heating rates (5, 10, 15, and 20°C/min) by using TG‐DSC. To calculate the kinetic parameters (Ea, A), three different kinetic models were used, including the Flynn‐Wall‐Ozawa (FWO), Kissinger‐Akahira‐Sunose (KAS), and Starink methods. The average Ea values for FWO, KAS, and Starink methods are 85.2141, 80.37217, and 80.74315 kJ mol−1, respectively. Furthermore, the reaction mechanism and thermodynamic parameters (ΔH, ΔG, and ΔS) were simulated and calculated to further comprehend the pyrolysis process. The residual carbon (char) obtained after the pyrolysis process was further characterized by SEM‐EDX and BET to quantify the morphology, surface area, and porosity. SEM results revealed that the residual carbon has a honey‐comb like porous structure, whereas BET analysis reflects that PP800 possesses the highest specific surface area (SSA) ~ 1288.97 m2 g−1 with an average pore diameter of 8.85 nm. Thus, it has enormous potential to be used as adsorbent and active electrode material in energy storage devices. [ABSTRACT FROM AUTHOR]

Manufacturing honeycomb-structured catalysts require a careful understanding of the microstructure of the solid substrate and its dependence on thermalprocessing conditions. Herein, it is the thermal responses of microcracks in an uncoated microcracked aluminum titanate honeycomb catalyst is investigated by analyzing the material's resonance frequency using the high-temperature impulse excitation technique. The resonance frequencies are presented as Young's modulus values to avoid sample size effects. Dynamic Young's modulus measurements show closed-loop hysteresis due to microcracks healing and reopening, causing a reversible response. The hysteresis is further used to understand microcracks' dependence on critical thermal-processing conditions used in a catalyst manufacturing plant, including peak operating temperature (800--1000 °C), dwell period (1--3 h), and heating rates (1--5 °Cmin-1). Microcracks are observed to have two healing responses: instantaneous and delayed healing. Both responses significantly influence the design of catalyst manufacturing. Complete reopening of microcracks from their healing temperature (1150 °C) is a very time-consuming process (50--60 h).However, it is shown in the analysis that microcrack relaxation is a critical phenomenon that must be considered in quality-controlled environments. [ABSTRACT FROM AUTHOR]

Free and forced vibration characteristics of composite sandwich beams with single‐core (SC) and dual‐core (DC) are investigated in this study. The wet hand‐layup technique is followed to make the composite face sheet, and honeycomb cores are 3D printed using the fused filament fabrication method. The natural frequencies of SC and DC sandwich beams were measured using experimental modal tests and validated through a three‐dimensional finite‐element model. Also, parametric studies on the geometry of composite structures are performed to scrutinize the effect of DC sandwich beams with different ply orientations, length‐to‐breadth ratios, core thickness, and core cell wall thickness. In addition, the transverse vibration responses of SC and DC sandwich beams are examined under harmonic force excitations at different end conditions. The study result shows that the sandwich beam's vibration behavior is enhanced by the inclusion of a core. [ABSTRACT FROM AUTHOR]

This study investigated the feasibility of using natural fiber material to create honeycomb cores, as traditional cores made of aluminum, Nomex, and petroleum‐based materials are not environmentally friendly. The natural fiber honeycomb cores were formed using a 3D printed molding process and were bonded to flax and glass fiber facings to improve the durability of the structures. The addition of cellulose and nanoclay to the adhesive enhanced the flexural strength of the structures by 7.43% and 10.48%, respectively, while also absorbing 8.67% and 8.91% more impact energy than structures bonded with epoxy alone. However, the compressive strength decreased by 10.79% and 13.6% with the addition of cellulose and nanoclay to the adhesive, respectively. Tensile properties were also studied, and the tensile strength of hybrid facings was found to be 69.45% higher than those using solely flax facings. Additionally, hybrid facings effectively reduced moisture uptake, making them hydrophobic and reducing water uptake by 46.89% compared to solely flax facings. Overall, natural fiber honeycomb composite structures showed comparable performance to Nomex and aluminum honeycomb composites, offering favorable properties while being constructed using environmentally friendly materials. The efficient manufacturing process using additive manufacturing makes these structures readily customizable and scalable, leading to their implementation in numerous applications such as aerospace, automotive, and marine industries. [ABSTRACT FROM AUTHOR]

In this study, aluminum honeycomb cells were filled with polymethacrylimide (PMI) foam of high strength and stiffness, and carbon fiber reinforced composite (CFRC) skins were added to create a composite sandwich structure. Nine types of specimens with varying cell node spacing and foam density were constructed, and stiffness equations were derived. To compare the performances of aluminum honeycomb and PMI foam sandwich structures, their compressive responses were examined using edgewise and flatwise compression tests. Moreover, the failure was analyzed using finite element methods (FEM). Analytical and numerical models were used to investigate the size effects of rib width, rib angle, and node spacing. [ABSTRACT FROM AUTHOR]

In order to solve the short stabilization time of the water‐in‐oil emulsion binder system and the shortcomings of the critical blast size of the explosive ink molding sample, a water‐in‐oil emulsion binder was designed with polyvinyl alcohol (PVA) aqueous solution as the aqueous phase, fluorocarbon resin (FEVE) ethyl acetate solution as the oil phase, and toluene diisocyanate (TDI) added to modify the water‐in‐oil emulsion binder. The hexanitrohexaazaisowurtzitane(CL‐20)based explosive ink was made by incorporating submicron CL‐20 into the binder system, and the print‐formed samples were tested for microscopic morphology, crystallographic analysis, mechanical susceptibility, and detonation transmission performance. The results showed that the explosive ink's viscosity was moderate and suitable for direct printing, and the formed sample's surface particles were uniformly dispersed and had a honeycomb structure. The crystal form of CL‐20 explosive in the explosive ink did not change, the molded sample's impact and frictional sensitivities were 1 J and 32 N lower than those of submicron CL‐20, respectively, and the detonation velocity of the molded sample was 6655 m/s. The critical detonation size and critical detonation thickness were 1×0.0078 mm and 0.1 mm, respectively, and a critical detonation corner turning of 90°–160° could be achieved. The results show that the prepared binder system is stable for a long time, and the explosive ink molding samples have excellent blast transmission performance. [ABSTRACT FROM AUTHOR]

Mixed‐anion compounds have attracted growing attentions, but their synthesis is challenging, making a rational search desirable. Here, we explored LaF3‐LaX3 (X=Cl, Br, I) system using ab initio structure searches based on evolutionary algorithms, and predicted LaF2X and LaFX2 (X=Br, I), which are respectively isostructural with LaHBr2 and YH2I, consisting of layered La‐F blocks with single and double ordered honeycomb lattices, separated by van der Waals gaps. We successfully synthesized these compounds: LaF2Br and LaFI2 crystallize in the predicted structure, while LaF2I is similar to the predicted one but with different layer stacking. LaF2I exhibits fluoride ion conductivity comparable to that of non‐doped LaF3, and has the potential to show better ionic conductivity upon appropriate doping, given the theoretically lower diffusion energy barrier and the presence of soft iodine anions. This study shows the structure prediction using evolutionary algorithms will accelerate the discovery of mixed‐anion compounds in future, in particular those with an ordered anion arrangement. [ABSTRACT FROM AUTHOR]

Mixed‐anion compounds have attracted growing attentions, but their synthesis is challenging, making a rational search desirable. Here, we explored LaF3‐LaX3 (X=Cl, Br, I) system using ab initio structure searches based on evolutionary algorithms, and predicted LaF2X and LaFX2 (X=Br, I), which are respectively isostructural with LaHBr2 and YH2I, consisting of layered La‐F blocks with single and double ordered honeycomb lattices, separated by van der Waals gaps. We successfully synthesized these compounds: LaF2Br and LaFI2 crystallize in the predicted structure, while LaF2I is similar to the predicted one but with different layer stacking. LaF2I exhibits fluoride ion conductivity comparable to that of non‐doped LaF3, and has the potential to show better ionic conductivity upon appropriate doping, given the theoretically lower diffusion energy barrier and the presence of soft iodine anions. This study shows the structure prediction using evolutionary algorithms will accelerate the discovery of mixed‐anion compounds in future, in particular those with an ordered anion arrangement. [ABSTRACT FROM AUTHOR]

Mixed‐anion compounds have attracted growing attentions, but their synthesis is challenging, making a rational search desirable. Here, we explored LaF3‐LaX3 (X=Cl, Br, I) system using ab initio structure searches based on evolutionary algorithms, and predicted LaF2X and LaFX2 (X=Br, I), which are respectively isostructural with LaHBr2 and YH2I, consisting of layered La‐F blocks with single and double ordered honeycomb lattices, separated by van der Waals gaps. We successfully synthesized these compounds: LaF2Br and LaFI2 crystallize in the predicted structure, while LaF2I is similar to the predicted one but with different layer stacking. LaF2I exhibits fluoride ion conductivity comparable to that of non‐doped LaF3, and has the potential to show better ionic conductivity upon appropriate doping, given the theoretically lower diffusion energy barrier and the presence of soft iodine anions. This study shows the structure prediction using evolutionary algorithms will accelerate the discovery of mixed‐anion compounds in future, in particular those with an ordered anion arrangement. [ABSTRACT FROM AUTHOR]

Mixed‐anion compounds have attracted growing attentions, but their synthesis is challenging, making a rational search desirable. Here, we explored LaF3‐LaX3 (X=Cl, Br, I) system using ab initio structure searches based on evolutionary algorithms, and predicted LaF2X and LaFX2 (X=Br, I), which are respectively isostructural with LaHBr2 and YH2I, consisting of layered La‐F blocks with single and double ordered honeycomb lattices, separated by van der Waals gaps. We successfully synthesized these compounds: LaF2Br and LaFI2 crystallize in the predicted structure, while LaF2I is similar to the predicted one but with different layer stacking. LaF2I exhibits fluoride ion conductivity comparable to that of non‐doped LaF3, and has the potential to show better ionic conductivity upon appropriate doping, given the theoretically lower diffusion energy barrier and the presence of soft iodine anions. This study shows the structure prediction using evolutionary algorithms will accelerate the discovery of mixed‐anion compounds in future, in particular those with an ordered anion arrangement. [ABSTRACT FROM AUTHOR]

In this paper, a honeycomb Si3N4 ceramic was fabricated by 3D printing with a well‐preserved structure. The effects of Si3N4 content on the rheological properties of Si3N4/sol–silica ink and the printing resolution of products were investigated. The microstructure, phase composition, liner shrinkage rate, and fracture behavior of printed samples before and after sintering were systematically characterized in detail. The results showed that the modified inks had the optimized rheological properties, and the stress–shear rate curves corresponding to each slurry could be well described by Bingham and Herschel–Bulkley fluid models. The corresponding slump rates of the printed samples with different Si3N4 to sol–silica mass ratios were all lower than 4%, and the linear shrinkage rate of all of the samples after sintering was below 20%. The fracture behavior under compressive loading of the honeycomb Si3N4 ceramics tended to be non‐catastrophic fractures both before and after sintering. The compressive strengths of all of the printed samples decreased with the increase of the Si3N4 content, and the highest compressive strength of the honeycomb ceramics could reach 131.2 MPa after sintering at 1600°C, which was about 366.9% higher than that of the samples in green state prior to the sintering. [ABSTRACT FROM AUTHOR]

This article proposes a compact low‐pass filter (LPF) using a miniaturized capacitor, and honeycomb cavity based on the substrate integrated suspended line platform. A new method for miniaturizing capacitors is proposed, and simultaneously honeycomb cavities are adopted to extend the stopband. As a design case, a seven‐order quasi‐lumped‐element LPF with a cutoff frequency of 0.6 GHz is designed, fabricated, and tested. The size of the LPF is 0.085λg × 0.015λg × 0.012λg, and a wide stopband from 0.82 to 67 GHz with a suppression level greater than 20 dB is obtained. [ABSTRACT FROM AUTHOR]

The valley contrasting physics in photonic systems gives rise to many interesting phenomena such as photonic valley Hall effect and robust valley transport. However, most reported valley photonic crystals are demonstrated in the honeycomb lattice. Here, unidirectional bulk modes and robust edge modes are numerically and experimentally shown in triangular photonic crystals. By switching the phase vortex of an input chiral source, dynamic unidirectional propagation of bulk modes at different valleys is observed. Unidirectional edge modes are also demonstrated on the domain wall between two distinct triangular photonic crystals. In addition, robust edge modes around sharp corners are experimentally confirmed. This work paves the way for the realization of dynamic unidirectional photonic transport and robust valley transport in photonic crystals. [ABSTRACT FROM AUTHOR]

Herein, vibrational behavior of functionally graded (FG) smart piezoelectric sandwich plates with honeycomb core resting on viscoelastic foundation under the effect of 2D magnetic field is presented. By varying the magnetic‐field magnitude and its direction, the vibrations can be controlled. The plate is composed of two FG piezoelectric layers bonded with honeycomb structure as a mid‐layer. Magnetic Lorentz force will be deduced via Maxwell's relations. A new quasi‐3D plate theory considering the shear and normal deformations is incorporated to evaluate the displacements. The governing equations of motion are introduced via Hamilton's principle. Galerkin technique is considered to solve the motion equations for different boundary conditions. Influences of the magnetic field, boundary conditions, electric voltage, and core thickness on the eigenfrequency of the FG sandwich piezoelectric plate are illustrated. It is found that considering the effect of the magnetic field on the smart devices increases their vibrations, which may lead to an increment in the energy harvested from them. Further, when the magnetic field is applied along the length of the rectangular plate, the vibrations are reduced and vice versa. [ABSTRACT FROM AUTHOR]

Structural hierarchy has become a popular technique to improve the crashworthiness of engineering structures. A study is conducted to explore the interaction between hierarchical geometries and determine the optimum honeycomb configuration that improves crashworthiness. Nine distinct second‐order vertex‐based hierarchical honeycombs are constructed by iteratively replacing the vertices of a square‐based honeycomb with squares, circles, and octagons. Validated finite element models are then established to investigate the out‐of‐plane crashworthiness performance. Subsequently, the effect of the hierarchical geometry combinations and cell length ratios on the crashworthiness performance of the nine honeycombs is studied. The study showed that the second‐order hierarchical honeycomb exhibited superior crashworthiness performance under the same relative density compared to the regular and first‐order hierarchical square honeycombs. The study determined that the circle is a suitable matching geometry in the first‐ and second‐order hierarchies for improving the crashworthiness of a square‐based honeycomb. Using Complex Proportional Assessment, the Square‐Circle‐Circle ranked as the optimum structure for crashworthiness application. [ABSTRACT FROM AUTHOR]

Flexible Zn‐ion batteries (ZIBs) emerge as a promising entrant for flexible and safe energy systems in the post‐Li era, while the instability of Zn anode including inferior flexibility, uncontrollable plating, and dendrite growth remains a challenge. Naturally inspired, a topology‐optimized biomimetic honeycomb Zn (BH‐Zn) anode through mechanical‐electrochemical processing is demonstrated. Numerical simulations and experimental observations reveal the BH‐Zn engenders smooth current–stress–thermal field distributions, concurrently realizing the multi‐field regulation effect and boosted stability. After in situ alloying, the BH‐Zn enables half‐diminished voltage polarization, superior electrochemical stability of 2000 h cycling, and thermal stability even at 30 mA cm−2. Moreover, the assembled ZIBs manifest over 20 times enhanced capacity retention and are integrated as a self‐powered wearable system for real‐time health monitoring. This strategy can be extended to customizable metal anodes and promises to be applied in stable flexible batteries. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) are becoming promising candidates for energy storage devices due to the low cost, abundant reserves, and excellent electrochemical performance. As the most important unit, layered cathodes attract much attention, where honeycomb‐layered‐oxides (HLOs) manifest outstanding structural stability, high redox potential, and long‐life electrochemistry. Here, recent progress on HLOs as well as Na3Ni2SbO6 and Na3Ni2BiO6 as two representative materials are introduced, and the crystal and electronic structure, electrochemical performance, and modification strategies are summarized. The advanced high nickel HLOs are highlighted toward development of state‐of‐the‐art sodium‐ion batteries. This review would deepen the understanding of superstructure in layered oxides, as well as structure–property relationship, and inspire more interest in high output voltage, long lifespan sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

The brittleness of Si3N4 ceramics has always limited its wide application. In this paper, Si3N4 ceramics were prepared based on foam. Combining the unique honeycomb structure of the ceramic foams and the self‐toughening mechanism of Si3N4, the strengthening and toughening of Si3N4 ceramics can be further achieved by adjusting the microstructure of Si3N4 ceramic foams. The powder particles are self‐assembled by particle‐stabilized foaming to form a foam body with a honeycomb structure. It was pretreated at different temperatures (1450–1750°C). The microstructure evolution of foamed ceramics at different pretreatment temperatures and the conversion rate of α‐Si3N4 to β‐Si3N4 at different pretreatment temperatures were explored. Then the foamed ceramics with different microstructures are hot‐press sintered to prepare Si3N4 dense ceramics. The effects of different microstructures of foamed ceramics on the strength and toughness of Si3N4 ceramics were analyzed. The experimental results show that the relative density of Si3N4 ceramics prepared at a particle pretreatment temperature of 1500°C is 97.8%, and its flexural strength and fracture toughness are relatively the highest, which are 1089 ± 60 MPa and 12.9 ± 1.3 MPa m1/2, respectively. Compared with the traditional powder hot‐pressing sintering, the improvement is 21% and 33%, respectively. It is shown that this method of preparing Si3N4 ceramics based on foam has the potential to strengthen and toughen Si3N4 ceramics. [ABSTRACT FROM AUTHOR]

2D materials beyond graphene and in particular 2D semiconductors have raised interest due to their unprecedented electronic properties, such as high carrier mobility or tunable bandgap. Blue phosphorene is an allotrope of black phosphorene that resembles graphene as it presents a honeycomb structure. However, it is known to have semiconductor character and the crucial point is to determine whether this hexagonal phase of phosphorene presents Dirac fermions as in graphene. Here, the first compelling experimental evidence of Dirac fermions in blue phosphorene layer grown on Cu(111) surface is presented. The results highlight the formation of a highly ordered blue phosphorene sheet with a clear Dirac cone at the high symmetry points of the Brillouin Zone. The charge carriers behave as massless relativistic particles. Therefore, all the expectations held for graphene, such as high‐speed electronic devices based on ballistic transport at room temperature, may also be applied to blue phosphorene. [ABSTRACT FROM AUTHOR]

In this study, a series of adsorbents with honeycomb structure that hyperbranched polyethyleneimine (PEI) functionalized carboxymethyl chitosan (CMC/PEI) are successfully designed for acteoside (ACT) separation. The microstructures of adsorbents are adjusted to optimum by changing the molecular weight and addition amount of PEI. The scanning electron microscope (SEM) and N2 adsorption‐desorption experiment results show that CMC/PEI‐70000‐4.5g presents the honeycomb structure with the highest specific surface area and the largest pore volume. The honeycomb structure has the multiple internal cavities, which provide sufficient space for accommodating and adsorbing ACT molecules, improving the adsorption capacity. Furthermore, this work introduces PEI on the inner and outer surface of pores and forms an amino layer, which has high‐affinity for ACT molecules and realizes the excellent selectivity. Therefore, CMC/PEI‐70000‐4.5g shows the highest adsorption capacity of 125.67 mg g−1 and selectivity of 5.38. The adsorption process of ACT can be fitted by pseudo‐second‐order kinetics, intraparticle diffusion, and Langmuir isotherm models. High‐affinity (hydrogen bond, hydrophilic attraction, and Van der Waals force) is proposed as the main driving forces for adsorption between CMC/PEI‐70000‐4.5g and ACT. This work provides a strategy to synthesize the adsorbents with honeycomb structure for bioactive components separation from natural products. [ABSTRACT FROM AUTHOR]

The core task for Mott insulators includes how rigid distributions of electrons evolve and how these induce exotic physical phenomena. However, it is highly challenging to chemically dope Mott insulators to tune properties. Herein, we report how to tailor electronic structures of the honeycomb Mott insulator RuCl3 employing a facile and reversible single‐crystal to single‐crystal intercalation process. The resulting product (NH4)0.5RuCl3⋅1.5 H2O forms a new hybrid superlattice of alternating RuCl3 monolayers with NH4+ and H2O molecules. Its manipulated electronic structure markedly shrinks the Mott–Hubbard gap from 1.2 to 0.7 eV. Its electrical conductivity increases by more than 103 folds. This arises from concurrently enhanced carrier concentration and mobility in contrary to the general physics rule of their inverse proportionality. We show topotactic and topochemical intercalation chemistry to control Mott insulators, escalating the prospect of discovering exotic physical phenomena. [ABSTRACT FROM AUTHOR]

Aerogels, shaped as fibers, films, as well as monoliths, have demonstrated a plethora of applications in both academia and industry due to charming properties including ultralow density, large specific surface area, high porosity, etc., however studies on more complicated aerogel forms (e.g., honeycombs) with more powerful applications have not been fully explored. Herein, the Kevlar aerogel honeycomb is firstly constructed through a dry ice‐assisted 3D printing method, where the Kevlar nanofiber ink is printed directly in dry ice freezing atmosphere, followed by supercritical fluid drying. The subsequent 3D Kevlar/shear‐stiffening gel (SSG) honeycomb (3D‐KSH) can be obtained by selective nanoconfining of SSG into nanopores of the aerogel skeleton wall (with the loading amount of 93 wt%) rather than into open honeycomb channels, solving the leakage, creep deformation, and shape design infeasibility of the SSG. Combining the advantages of Kevlar, honeycomb and SSG, the fabricated 3D‐KSH shows obvious smart responsive behavior to external stimulus. Additionally, the 3D‐KSH has high strain rate sensitivity (sensitivity factor of 4.16 × 10−4) and excellent impact protection performance (energy absorption value up to 176 J g−1 at the strain rate of 6300 s−1), which will significantly broaden application prospect in some intelligent protection fields. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA)—based honeycomb samples with different cell sizes and thickness were prepared using the fused filament fabrication (FFF) 3D printing technology and used to build sandwiched multilayer structures consisted of the honeycomb as the core component and poly(vinylidene fluoride) (PVDF) and/or PVDF/carbon nanotube (CNT) nanocomposites as top and bottom layers. The effect of the honeycomb design (cell size and thickness) and the presence and nature of the impedance matching layer on the microwave absorbing properties of the corresponding structures was investigated in the X‐band (8.2–12.4 GHz) and Ku‐band (12.4–18 GHz). For the systems without matching layer or with neat PVDF film as the matching layer, the honeycomb with larger thickness (5 mm) and larger cell size resulted in better electromagnetic wave attenuation but narrow frequency bandwidth with RL below −10 dB. The best combination minimum RL value (−18 to −14 dB) and broad frequency bandwidth with attenuation higher than 90% (around 8 GHz) was achieved with honeycomb of 2 mm thickness sandwiched by PVDF/CNT05 as the matching layer and bottom layer constituted by PVDF/CNT1 film, regardless the cell size of the honeycomb. These results indicate the PLA honeycomb as promising candidate as component for multilayer microwave absorbing materials and open new possibilities of applications of FFF technology for designing flexible, lightweight, and low‐cost materials to be used in both civil and military industries. [ABSTRACT FROM AUTHOR]

BACKGROUND: The poor gelling and emulsification properties of pea protein (PeaP) limit its application in gel‐based products. In this study, a strong hydrogel and a high internal phase emulsion (HPLE) gel of PeaP were constructed by covalent cross‐linking of transglutaminase (TGase) assisted by high‐intensity ultrasound. RESULTS: Ultrasound promoted the catalytic efficiency of TGase, with the gel‐point temperature dropping from 44 °C to 28 °C after 10 min of ultrasound. As the ultrasound time increased from 1 min to 10 min, the microstructure of the hydrogel also changed from an irregular macropore structure to a relatively homogeneous honeycomb structure. This was accompanied by an improvement in gel strength, water holding capacity, and ultimate stress. Ultrasound enhanced the binding of water to PeaP, but had little effect on the water‐locking ability of the network structure. Ultrasonication improved the self‐supporting ability of the HPIE gels. The oil droplets within the HPIE gels were closely aligned to form a hexagonal structure. The PeaP layer was further cross‐linked by TGase, strengthening the network structure. High internal phase emulsion gel displayed a higher gel strength, viscosity, and good self‐healing ability under 1 min ultrasound. Meanwhile, HPIE gel at 1 min of ultrasound could be printed with the highest clarity. CONCLUSION: This work provided some insights into improving the functional properties of PeaP, which is helpful for the design and development of PeaP‐based gel products. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Photonic crystals can be used to achieve high‐performance surface‐emitting lasers and enable novel photonic topological insulator devices. In this work, a GaAs/InGaAs heterojunction nanowire platform by selective area metalorganic vapor phase epitaxy for such applications is demonstrated. The nanowires are arranged into deformed honeycomb lattices on silicon‐on‐insulator substrate to exploit the quadrupolar photonic band‐edge mode. Core–shell and axial heterostructures are formed with their crystalline properties studied by scanning transmission electron microscopy. Room‐temperature, single mode lasing from both stretched and compressed honeycomb lattices within the telecom‐O band, with lasing threshold as low as 1.25 µJ cm−2 is demonstrated. The potential of using InGaAs nanowire‐based honeycomb lattices for small‐divergence surface‐emitting lasers and topological edge mode lasers is investigated. Finite‐difference time‐domain far field simulations suggest a sub‐10° beam divergence can be achieved thanks to the out‐of‐plane diffraction. [ABSTRACT FROM AUTHOR]