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Sealing treatment provides a strategy for the long-term performance of thermal spray coatings under actual working conditions. However, common sealants are mainly limited to improving the corrosion resistance of coatings, neglecting applications in more complex environments where they are subject to simultaneous corrosion and wear. Herein, a novel organic-inorganic hybrid composite sealant, composed of self-lubricating MoS 2 nanoparticles and environmentally friendly waterborne silicone modified acrylic resin (WBS-ACR), was successfully prepared in the pores and micro-defects of plasma-sprayed HEA coatings by one-step hydrothermal method. The results indicate that MoS 2 nanosheets are uniformly synthesized in resin materials through precursor hydrothermal reactions. The hybrid sealants are filled densely in the micro-defects of HEA coatings with a maximum penetration depth greater than 180 μm. The tribological and electrochemical results indicate that the hybrid sealant exhibits similar anti-wear performance, but two orders of magnitude lower corrosion currents than that of pure MoS 2 sealant. In comparison to the pure resin sealant, the hybrid sealant retains its excellent corrosion resistance while increasing its wear resistance. The superior comprehensive performance of the novel organic-inorganic hybrid sealant could expand the application of thermal spray coatings into new fields. [ABSTRACT FROM AUTHOR]

A hybrid material consisting of an array of vertically ordered carbon nanotubes (CNTs) in porous anodic alumina was fabricated directly on oxidized Si substrates. Individual CNTs with vertical orientation were grown using the catalyst Ni nanoparticles (NPs) embedded in the pore walls of a thin template based on porous anodic alumina with a pore diameter of 40 ± 5 nm. The initial film was a two-layer Ti-Al structure on a Si/SiO 2 substrate. A vertically oriented porous structure was formed by anodizing the Al layer. Electrochemical deposition was used to form the catalyst Ni-NPs with dimensions of 30 ± 5 nm. CNTs were synthesized by high-temperature chemical vapor deposition. Scanning and transmission electron microscopy, Raman spectroscopy, and X-ray diffraction were used to analyze the surface morphology and microstructure of the composite nanostructures. The CNT length was (0.6–1.5) μm, and the CNT spacing was 110 ± 10 nm. It is expected that the resulting structure will serve as a basis for the development of CNT-based electrodes for electrochemical impedance biosensors. Electrochemical impedance spectroscopy was used for the electrochemical characterization of the fabricated CNT-based electrodes. The results showed that the CNT-based electrodes are characterized by improved electron transfer kinetics. [ABSTRACT FROM AUTHOR]

In today's world, the efficient preparation of clean energy has become a problem for every country. Hydrogen is a very clean and easy to prepare energy source. In this paper, a hybrid materials of (Fe 6 (OH) 12 (CO 3)) and sulphide (Ni 9 S 8 /Co 9 S 8) was demonstrated as a catalytic electrode for efficient oxidation reaction in seawater and urea. The catalysts were prepared by a three-step hydrothermal-sulfuration-hydrothermal reaction, and the layered composites of hydroxides and sulfides were co-grown into nano-arrays, which exposed more reaction centers and shortened the electron transfer path. The three metal cations were also able to demonstrate different corrosion resistance and excellent adsorption properties for different environments, allowing the catalyst to present better electrochemical activity in seawater as well as in urea solution. In the oxidation reaction in urea solution (1 M KOH+0.5 M urea), the required voltage was only 1.33 V at a current intensity of 50 mA/cm2, and in the water oxidation reaction in seawater, the required voltage was only 1.47 V at a current intensity of 50 mA/cm2 for Ni 9 S 8 @Co 9 S 8 @Fe 6 (OH) 12 (CO 3). Unfortunately, the durability of the catalyst need to be improved, the current density dropped from 40 mA/cm2 to 35 mA/cm2 and then remained for 12 h. Meanwhile, the comparison of electrochemical performance tests was performed before and after the IT test, it can be clearly seen that the overall performance of Ni 9 S 8 @Co 9 S 8 @Fe 6 (OH) 12 (CO 3) decreased after the stability test, which may be related to the shedding of active species from the surface of the catalyst. As you can see through density functional theory (DFT) that Ni 9 S 8 can promote the adsorption energy of urea and Co 9 S 8 lowers the barrier to electron conduction. Many conjectures were made and confirmed in this study, and finally, it is hoped that seawater as well as industrial wastewater can be better utilized for the production of clean energy. The NiCoS@Fe 6 (OH) 12 (CO 3) catalyst present superior electrocatalytic performance in 1.0 M KOH + seawater and urea electrolyte solution. [Display omitted] • NiCoS@Fe 6 (OH) 12 (CO 3) electrodes was synthesized for the first time through hydrothermal processes. • The working potential of NiCoS@Fe 6 (OH) 12 (CO 3) electrode is only 1.33 V at 50 mA cm−2 for UOR. • The introduction of Ni 9 S 8 gives a large enhancement in the adsorption energy of urea for NiCoS@Fe 6 (OH) 12 (CO 3). [ABSTRACT FROM AUTHOR]

To assess the impact of elastic gradients formed among restorative material, cement, and substrate on the fracture resistance of tri-layer restorative systems. Four CAD/CAM materials were utilized, two glass-ceramics (IPS e.max CAD, Vita Suprinity) and two resin-ceramic hybrids (Vita Enamic, Lava Ultimate). Their fracture resistance was examined by biaxial flexure (n = 8) and Hertzian indentation (n = 10) tests. Statistical analysis was conducted using ANOVA and Tukey tests (p = 5 %). Finite element analysis (FEA) was employed to simulate the Hertzian indentation test and elucidate the stress-fields formed on the intaglio surface below the loading area. The biaxial flexural strength (MPa) of glass-ceramics exceeded the hybrid materials (e.max 417a, Suprinity 230b, Enamic 138c, and Lava Ultimate 183bc). Conversely, the load-bearing capacity (N) of the materials bonded to dentin analog demonstrated the opposite trend, with the hybrid materials achieving superior results (e.max 830 C, Suprinity 660D, Enamic 1822B, and Lava Ultimate 2593 A). The stress-fields observed by FEA were coherent with the experimental results for Hertzian flexural stresses (MPa): e.max 501 A, Suprinity 342 C, Enamic 406B, whereas no tensile stress was observed at the intaglio surface of Lava Ultimate. Detailed analysis of the fracture resistance of the tri-layer restorative systems showed that the elastic gradients play a more significant role than the flexural strength of the restorative materials. The coherence of the elastic moduli between the restorative material and supporting structures results in reduced tensile stress concentration at the intaglio surface beneath the loading area and enhances the ability to withstand load. • The biaxial flexural strength of glass-ceramics exceeds that of the hybrid materials. • When bonded to "dentin", the load-bearing capacity is greater for hybrid materials. • When bonded to "dentin", no flexural stress is observed for Lava Ultimate. • Elastic gradients are critical to the fracture resistance of restorative materials. [ABSTRACT FROM AUTHOR]

Observing the degradation rate of the bone fillers upon implantation enables us to predict the next stages of healing process. Strong luminescent property of the biocompatible carbon quantum dots accompanied by the high bioactivity of the 45S5 bioglass, bearing an antibiotic drug, can form reliable bone filler with detectable degradation rate via bioimaging. This study reported the preparation of fluorescent carbon quantum dots/45S5 (CQDs/45S5) nanohybrids via the chemical precipitation procedure for the first time. The pyrolysis of the citric acid was carried out to achieve the fluorescent N-doped CQDs with an average size of around 11 nm. The physicochemical and microstructural characteristics of the obtained materials were studied by XRD, FTIR and FESEM, respectively, Ultraviolet visible (UV–Vis) and photoluminescence (PL) spectroscopies were employed to investigate the features of the carbon dots as well as hybrid materials. The PL spectroscopy analysis indicated the in-vitro luminescent emission of the CQDs/45S5 nanohybrids compared to 45S5 bioglass. Around 22 μg of DOX could adhere to 1 mg of the nanohybrids after 12 h of contact, proposed that more quantity of particles were needed to adsorb higher amount of drug. The drug release study indicated a fast release pattern of DOX (90 %) during the first hours. The in-vitro bioactivity and biocompatibility results revealed the high capability of the BG/15 mL CQDs sample to deposit calcium phosphate with no toxic effects on the fibroblast cells. Consequently, the obtained nanohybrids could be promising trackable drug-vehicle candidates, as well as bone fillers, bone cements and implant coating materials. [ABSTRACT FROM AUTHOR]

Bistable composite shells are suitable candidates for deployable space structures due to high stiffness to weight ratio as well as large volume reduction. Nevertheless, impact performance of bistable composite shells conflicting with space debris have been rarely studied. In this paper deployable hybrid composites constructed with combinations of carbon–carbon, carbon–kevlar, kevlar–kevlar, high-energy-absorption graphene-reinforced polyurethane elastomers are developed, and their ballistic penetration behaviors are experimentally and computationally studied. The influences of ballistic velocity on the absorbed energy, the residual velocity and damage morphology of the targets are investigated in both deployed and coiled stable states. The results show that severe local damages were observed for the carbon–carbon and carbon–kevlar samples after penetration with various velocities even first cosmic velocity, and the sample of deployable hybrid composite shell yielded the best ballistic impact resistance. The total energy absorption performance of the hybrid composite structure was greatly improved by introducing graphene-reinforced polyurethane elastomers without losing the deployability. Additionally, investigation on the energy absorption capability of deployed laminated shells with various curvature radii indicated that the curvature radius had a significant effect on the anti-penetration performance. • Development of deployable composite shell structures. • Experimental and numerical penetration and damage analysis of deployable composite shells. • Effects of curvature radius and elastomer ply thickness on the energy absorption of deployable laminated shells. [ABSTRACT FROM AUTHOR]

In this study, the Al/B 4 C/Y 2 O 3 hybrid composites were produced by Al 2 O 3 and Y 2 O 3 interaction via hot pressing. Moreover, the influence of Y 2 O 3 on the properties of Al/B 4 C 10 wt% was investigated. The hot pressing was performed at 600 °C with pre-oxidized aluminium powder to produce the composites. The microstructure analyses revealed that Al/B 4 C/Y 2 O 3 hybrid composite production was achieved by Al 2 O 3 and Y 2 O 3 interaction, and the Y 4 Al 2 O 9 (YAM) phase was obtained in the Al–B 4 C/Y 2 O 3 5 % sample. The Y 2 O 3 addition increased the porosity content of the Al/B 4 C structure. However, wear rate and corrosion resistance of the Al/B 4 C were enhanced owing to the presence of Y 2 O 3. The wear rate of Al/B 4 C was reduced from 26.55·10−7 cm3/Nm to 5.68·10−7 cm3/Nm at 15 N test load. The increasing Y 2 O 3 content and the formation of the Y 4 Al 2 O 9 decreased the corrosion rate of the Al/B 4 C fom 0.0179 mm/year to 0.0051 mm/year. Also, corrosion damage was shifted from the matrix to the reinforcement zone in Al–B 4 C/Y 2 O 3 5 % sample, and the aluminium was protected owing to the presence of Y 2 O 3 and Y 4 Al 2 O 9. [ABSTRACT FROM AUTHOR]

The global water resource shortage has evolved into a pressing concern, necessitating the advancement of effective and environmentally sustainable water treatment techniques. Photocatalysis has surfaced as a hopeful technology for eliminating organic contaminants from wastewater because of its efficiency, cost-effectiveness, and eco-friendliness. Here, CeO 2 microspheres and Ni 0.5 Zn 0.5 Fe 2 O 4 (NiZn-ferrite) nanoparticles were synthesized using the hydrothermal method, followed by the fabrication of ternary hybrid composites CeO 2 /NiZn ferrite/multiwalled carbon nanotubes (MWCNT) via ultrasonic treatment. Various analytical techniques including XRD, FESEM, VSM, PL, BET and UV–Visible spectroscopy were employed to characterize the resulting synthesized samples. The hybrid ternary composites demonstrate remarkable efficiency in degradation of reactive red-35 dye through photocatalysis attributed to enhanced surface area. This efficiency is further enhanced when coupled with ultrasonic treatment, leading to a synergistic effect. The catalysts can be easily separated from the suspension due to their magnetic behaviour and thus hold great potential for utilizations in the field of wastewater treatment and environmental remediation. [ABSTRACT FROM AUTHOR]

The present study focuses on synthesizing a composite material comprising of nickel ferrite and carbon derived from cotton, to exhibit exceptional microwave absorption capabilities over a wide frequency range. By adopting a mechanical alloy method, the microwave-absorbing composite is developed. The microwave absorption characteristics of the developed composites are further unearthly in terms of their permittivity and permeability. Combining magnetic and dielectric phases produces better eddy current loss and polarization, which are primarily responsible for absorption characteristics. The developed composites are cast into rectangular pallets to evaluate microwave absorption characteristics and examined using a vector network analyzer within the 8.2–12.4 GHz frequency range. With a pallet thickness of 2.55 mm, the entire X-band frequency is effectively covered, yielding a remarkable minimum reflection loss of −20.46 dB at 10.01 GHz. The current work's findings, owing to the synergistic combination of nickel ferrite and carbonized carbon provide a practical approach for developing a hybrid material with remarkable electromagnetic performance. [Display omitted] • The composite comprising of both magnetic and non-magnetic phases has been developed with the mechanical alloying method. • Impedance matching characteristics of the developed lightweight NCF tailored effectively with varying weight percentages. • Achieved minimum reflection loss of −20.46 dB for NCF25 composition at 10.01 GHz with 2.55 mm coating thickness. [ABSTRACT FROM AUTHOR]

The ever-growing need for advancement in data storage technology demands materials that can be controlled by as many degrees as possible. In this regard, multiferroic materials that show response both in electric and magnetic dimensions are of great interest especially when being investigated in two-dimensional materials that have their potential applications. In this study, we have incorporated Lanthanum (La) doped Bismuth Ferrite (BLFO), and La and Selenium (Se) co-doped BFO (BLFSO) with two-dimensional layered titanium carbide (Ti 3 C 2 T x) from the class of MXene as hybrid composites. The structural, optical and morphological investigation validated the successful etching of MXene from MAX, successful hybrid formation with conserved crystal structure and new phases of titanium dioxide (TiO 2) detected when the samples underwent heat treatment. This heat treatment was performed in order to enhance the multiferroic properties owing to the presence of TiO 2. Our results showed that the heated BLFSO-embedded Ti 3 C 2 T x hybrid composite showed maximum remnant polarization and higher dielectric response when measured with respect to the varying electric field and at different frequencies. The prepared samples also exhibited tunable polarization response at an applied static magnetic field, unveiling their magnetoelectric properties. [ABSTRACT FROM AUTHOR]

The overuse of antibiotics and antitumor drugs has resulted in more and more extensive pollution of water bodies with organic drugs, causing detrimental ecological effects, which have attracted attention towards effective and sustainable methods for antibiotics and antitumor drug degradation. Here, the hybrid nanomaterial (g-C 3 N 4 @Fe/Pd) was synthesized and used to remove a kind of both an antibiotic and antitumor drug named mitoxantrone (MTX) with 92.0% removal efficiency, and the MTX removal capacity is 450 mg/g. After exposing to the hybrid material the MTX aqueous solution changed color from dark blue to lighter progressively, and LC-UV results of residual solutions show that a new peak at 3.0 min (MTX: 13.2 min) after removal by g-C 3 N 4 @Fe/Pd appears, with the simultaneous detection of intermediate products indicating that g-C 3 N 4 @Fe/Pd indeed degrades MTX. Detailed mass spectrometric analysis suggests that the nuclear mass ratio decreased from 445.2 (M+1H) to 126.0 (M+1H), 169.1 (M+1H), 239.2 (M+1H), 267.3 (M+1H), 285.2 (M+1H), 371.4 (M+1H) and 415.2 (M+1H), and the maximum proportion (5.63%) substance of all degradation products (126.0 (M+1H)) is 40-100 times less toxic than MTX. A mechanism for the removal and degradation of mitoxantrone was proposed. Besides, actual water experiments confirmed that the maximum removal capacity of MTX by g-C 3 N 4 @Fe/Pd is up to 492.4 mg/g (0.02 g/L, 10 ppm). [ABSTRACT FROM AUTHOR]

Nanocomposites of SrBi (2-X) (CF) X Nb 2 O 9 (SBNCF) (CF=CoFe 2 O 4 for X = 0.0 to 0.5 with a step increment of 0.1) were synthesized using the hydrothermal method and characterized for their structural, morphological, elastic, and optical properties. The incorporation of CF into SrBi 2 Nb 2 O 9 (SBN) resulted in hybrid composites with tailored properties. X-ray Diffraction (XRD) with Rietveld refinement analysis confirmed the formation of orthorhombic SBN and spinel CF phases. Field Emission Gun Scanning Electron Microscopy (FEG-SEM) revealed that SBN exhibits a plate-like morphology, with the incorporation of CF into the SBN matrix resulting in both plate-like and octahedral-shaped grains. The Brunauer–Emmett–Teller (BET) method was used to determine the pore radius and surface area, both of which were found to have increased, indicating an enhancement in photocatalytic performance. The presence of the constituent elements in the prepared compositions was confirmed by Energy Dispersive Spectroscopy (EDS). Fourier Transform Infrared Spectroscopy (FTIR) spectra were used to determine elastic properties, suggesting potential applications in electronic noise filtering. From Diffuse Reflectance Spectroscopy (DRS), a recognizable semiconducting behavior and band gap bowing were noticed in SBNCF nanocomposites on the obtained energy band gap values (2.20 eV–1.56 eV) compared to the SBN host matrix (3.16 eV). The materials exhibited strong emission peaks at 470 nm, 528 nm, 584 nm, and 703 nm upon the excitation of 425 nm light using Photoluminescence (PL) spectroscopy. The white emission was predominant at room temperature in all the produced samples and the corresponding color temperature values range from 5865.93 K to 7599.05 K from the CIE diagram. The SBNCF materials are promising candidates in photocatalytic reactions and white light-emitting diodes (w-LEDs) based on their enhanced optical properties. [ABSTRACT FROM AUTHOR]

Addressing the significant issues of sand burn-on defects and interfacial reaction in sand casted 13Cr9Mo1VNb steel castings, which notably compromise the quality of the steel castings, remains a persistent challenge. The interfacial behaviors between the novel mixed sands and the steel grade were investigated under various sands. The sintering behavior of the sands was also studied without liquid steel at various holding time. In the absence of the influence of molten steel, sintering of mixed chromite-MgO does not undergo solid-solid reaction, with no detected presence of liquid phase and 2MgO·SiO 2. The mixed sands undergo sintering reactions upon contact with molten steel, yet no liquid phase is detected. This is primarily attributed to the chemical reaction between MgO and the liquid phase, resulting in the formation of forsterite, leading to the near-complete liquid phase consumption. Magnesia grains can suppress the liquid phase sintering of chromite by 13Cr9Mo1VNb, thus weakening its sintering performance. The presence of 2MgO·SiO 2 , which exhibits excellent resistance to slag (liquid phase) and steel liquid corrosion, impedes the rising of the liquid phase. Consequently, this reduces the thickness of the adhesive layer and suppresses metal penetration. The production of 2MgO·SiO 2 diminishes with the escalation of MgO addition, which increases adhesive thickness and metal penetration as the magnesia content rises. Within the scope of this study, the incorporation of 20 % MgO is suggested to mitigate burn-on defects, which may represent an advantageous selection. [ABSTRACT FROM AUTHOR]

This work aims to demonstrate the effect of ZrO 2 and MgO inclusion into the Poly(methyl methacrylate) (PMMA). To fabricate novel hybrid composites via heat cure method, various composites (PZM2, PZM4 and PZM6) were synthesized in the system [(95-x) PMMA + 5 ZrO 2 + x MgO] (x = 2, 4, and 6) respectively. Density of the prepared composites were determined and varying between 1.035–1.152 g/cm3. X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) followed by EDAX and mechanical testing were performed to evaluate the fabricated composite properties. Moreover, to explore the structure of the fabricated composites the 13 C CP-MAS SSNMR and 1 H-13 C Phase-Modulated Lee Goldberg (PMLG) HETCOR Spectrum were recorded which clarify chemical shifting and motional dynamics of the composites. Mechanical tests were performed by UTM and the obtained parameters such as compressive strength, Young's modulus, fracture toughness, brittleness coefficient, flexural strength and flexural modulus are found to be in the range of 91–100 MPa, 0.48–0.51 GPa, 9.122–9.705 MPa.m1/2 , 0.66–0.815, 51.03–42.78 MPa and 499–663 MPa respectively. Some more mechanical parameters such as proportional limit, elastic limit, failure strength, modulus of resilience and modulus of toughness were also calculated. Furthermore, tribological properties were also determined and the coefficient of friction (COF) was decreased by 17.4 % and 38 % for composite PZM6 at 20 N and 40 N as compared to the composite PZM2 and the lowest wear volume of 1.55 mm3 was observed for PZM2, whereas the maximum volume loss of 5.64 mm3 is observed for composite PZM6. To check out the biocompatibility, cytotoxicity and genotoxicity of the fabricated composites the Trypan-blue assay was also performed for PZM2 and PZM6 composites. Dissection on the gut of larvae was also performed on the both composites followed by DAPI and DCFH-DA staining. Therefore, these synthesized samples can be used for the fabrication of denture materials. [Display omitted] • Synthesis of ZrO 2 and MgO reinforced denture-based resin composites via heat cure method. • Density of the composites were determined and varying between 1.035-1.152 g/cm3. • The structure of the fabricated composites was studied using the 13 C CP-MAS SSNMR and 1 H-13 C Phase-Modulated Lee Goldberg (PMLG) HETCOR spectrum. • The PZM6 composite shows the maximum compressive strength, 100 MPa. • To check out the biocompatibility, cytotoxicity and genotoxicity, the Trypan-blue assay was performed. [ABSTRACT FROM AUTHOR]

In this research, Al/18Cu/3WC/3MoS 2 (wt.%) multilayered hybrid composites were fabricated by accumulative roll bonding (ARB), and their electrical and mechanical properties were investigated. After seven ARB cycles, an Al-matrix multilayered hybrid composite with a uniform distribution of WC-MoS 2 particles and Cu islands was achieved. The presence of the WC-MoS 2 particles and Cu islands significantly affected the electrical and mechanical properties of the fabricated composites. The composite obtained after seven ARB cycles showed an enhanced strength of 259 MPa. Also, it was found that the electrical conductivity of the Al matrix decreased by applied strain (about 19 % IACS) and the presence of the WC-MoS 2 particles. By annealing the fabricated composite obtained from final cycles, the electrical conductivity increased from 54 % IACS to 71 % IACS. [ABSTRACT FROM AUTHOR]

Herein, a hybrid support of Nb-doped TiO 2 and carbon nanotubes (Nb x TO@CNT, x = Nb wt%) was successfully prepared by a facile hydrothermal method. Controlling the annealing temperature to form either anatase (ANb x TO@CNT) or rutile (RNb x TO@CNT) changed the effect of the Nb dopant in the TiO 2 structure. The Pt/RNb 10 TO@CNT electrocatalyst exhibits excellent oxygen reduction reaction activity and durability (E onset : 0.945 V vs. RHE; E 1/2 : 0.888 V vs. RHE; j L : −6.260 mA cm−2). Theoretical calculations predicted that the synergetic effect of Pt/RNb 10 TO@CNT improves the electrochemical performance. The strong metal-support interaction (SMSI) effect and the formation of oxygen vacancies due to the increased amount of Ti3+ was observed. Band-gap reorganization by the distortion of electronic structures was further confirmed by UV–visible spectrometry. Single-stack polymer electrolyte membrane fuel cell measurements showed the highly improved current density of Pt/RNb 10 TO@CNT (1.913 A cm−2 at 0.6 V) and low current degradation (6.3%) under identical conditions. We report a Nb-doped rutile TiO 2 @CNT hybrid catalyst support prepared by a facile method, namely RNb 10 TO@CNT, which exhibits enhanced activity and ultra-durability of Pt towards ORR by improved SMSI effect caused by Nb doping. [Display omitted] • Nb-doped rutile TiO 2 @CNT hybrid support was designed by a facile synthesis process. • Pt/Nb-doped rutile TiO 2 @CNT ORR catalyst showed reasonable activity and durability. • Nb doping not only controlled electronic structures but also enhanced SMSI effect. • Significantly improved sustainability was exhibited in a single-stack PEMFC cell. [ABSTRACT FROM AUTHOR]

• An optimisation methodology is proposed for shielding against Orbital Debris. • Hypervelocity impact models are developed to capture damage/fracture mechanisms. • The proposed models are validated against hypervelocity impact experiments. • The optimised configuration maximises protection and minimises areal density. Advancements in space exploration over the last few decades have led to a sharp increase in Micro-Meteoroid and Orbital Debris (MMOD), with the associated increased risk of hypervelocity impact on satellites and space structures. The Whipple shield can mitigate the effects of such impacts and current research is exploring further developments towards effective lightweight passive shielding technology to counter the damaging effects of MMOD. With the increase in MMOD and the prospect of increased space travel in the coming years and decades, it is vital that more research is conducted and improvements are made in the development and design of efficient, lightweight shielding technology to protect both unmanned and manned spacecraft against hypervelocity impacts (HVI). The optimisation of shield design for HVI is a high dimensionality problem, suited to advanced computational approaches. Key variables in HVI shield design that should inform the focus on optimisation include: impact velocity, rear wall thickness, projectile diameter and bumper thickness. A hybrid shield configuration and numerical model are proposed and validated, with alternating layers of aluminium (AL2024) and carbon fibre composites (CFRP, T300 woven-fabric) to form a 5 mm thick target plate consisting of 5 plies. The adaptive coupled FEM-SPH method is used to model the target plates. The proposed hypervelocity shield design optimisation methodology is based on Direct Simulation-based Genetic Algorithm (DSGA) optimisation and is implemented to optimise a multi-variable shield design space. Objective weightings are used to analyse and discuss results, referring to the ratio of the kinetic energy to the shield areal density objectives. A clear transition in the impact behaviour of the optimised MMOD shields is observed in the transition region from high-velocity to hypervelocity impact, where significant levels of kinetic energy dissipation are observed below the transition region, and lower energy dissipation at hypervelocity. The shield design optimisation results show that with a weighted kinetic energy to mass objective of 90:10, the kinetic energy of the back shield plate decreases significantly (62.7%) and the areal density can be reduced by more than 18%. Alternative configurations displayed sub-optimal results based on a trade-off between objective functions. [ABSTRACT FROM AUTHOR]

Additive manufacturing of ceramics has attracted large interest due to its unique ability to rapidly prototype, low cost, and increased geometric complexity. Material extrusion technique is often considered for processing and shaping fine and dense ceramic structures because of the high solid loading in ink. In this work, 8 mol.% yttria-stabilized zirconia ink with 70 wt% ceramic loadings was prepared to print zirconia samples in horizontal and vertical directions, following two different filament orientations: 0/90° and ±45°. The study's main objective was to evaluate printing design influences on mechanical properties. This was assessed through flexural testing and digital image correlation analysis. Experimental findings showed that samples printed horizontally with ±45° filament orientation displayed the highest strength. A detailed inspection of fracture surfaces revealed that printing defects were the critical failure location sites formed after sintering and intimately related to printing design issues. After that, a conductive sensor was integrated into the surfaces of 3D-printed specimens by screen-printing silver-based conductive ink to analyze the structural health of zirconia samples. The sensing capabilities of printed conductive patterns were investigated using the four-point bending tests. The results demonstrated that the electrical resistance of the printed silver patterns increased as the applied load on zirconia substrates rose. It indicates that hybrid material extrusion and screen printing techniques are favored ways to manufacture sensors for structural detection of advanced 3D-printed ceramics. [ABSTRACT FROM AUTHOR]

An increasing number of CAD/CAM (computer-aided design/computer-aided manufacturing) hybrid materials have been introduced to the dental market in recent years. In addition, CAD/CAM hybrid materials for additive manufacturing (AM) are becoming more attractive in digital dentistry. Studies on material microstructures using micro-computed tomography (µ-CT) combined with scanning electron microscopy (SEM) have only been available to a limited extent so far. One CAD/CAM three-dimensional- (3D-) printable hybrid material (VarseoSmile Crown plus) and two CAD/CAM millable hybrid materials (Vita Enamic; Voco Grandio), as well as one direct composite material (Ceram.x duo), were included in the present study. Cylindrical samples with a diameter of 2 mm were produced from each material and investigated by means of synchrotron radiation µ-CT at a voxel size of 0.65 µm. Different samples from the same materials, obtained by cutting and polishing, were investigated by SEM. The 3D-printed hybrid material showed some agglomerations and a more irregular distribution of fillers, as well as a visible layered macrostructure and a few spherical pores due to the printing process. The CAD/CAM millable hybrid materials revealed a more homogenous distribution of ceramic particles. The direct composite material showed multiple air bubbles and microstructural irregularities based on manual processing. The µ-CT and SEM analysis of the materials revealed different microstructures even though they belong to the same class of materials. It could be shown that µ-CT and SEM imaging are valuable tools to understand microstructure and related mechanical properties of materials. • µ-CT and SEM imaging are valuable tools to understand material microstructure. • Mechanical properties might be derivable from the microstructure of the material. • Deviations from a homogeneous microstructure may influence material properties. [ABSTRACT FROM AUTHOR]

An additive manufacturing process and subsequent pyrolysis cycle were used to fabricate SiC matrix/carbon fiber hybrid composites. The matrix was fabricated using a mixture of preceramic polymer and acrylate monomers, while polyacrylonitrile (PAN) precursor was used to fabricate fibers via electrospinning. The precursor matrix and reinforcing fibers at 0, 2, 5, or 10 wt% were printed using digital light processing, and both were simultaneously pyrolyzed to yield the final ceramic matrix composite structure. After pyrolysis, XRD and SEAD analysis proved the existence of SiC nanocrystals and turbostratic carbon structure in the matrix, while the reinforcement phase was shown to have a turbostratic carbon structure similar to commercial carbon fibers. Thermogravimetric analysis (TGA) in air up to 1400 °C was used to evaluate the oxidation resistance of this material. TGA results showed some weight loss due to oxidation of SiC and/or carbon up to about 900 °C, followed by weight gain to about 1200 °C due to the formation of a protective SiO 2 layer. Although increasing carbon fiber content negatively impacted the total mass loss for the first heating cycle, exposure of the composite to second-run air revealed negligible weight loss. This is explained by SiO 2 layer formation which acts as a protective film that prevents oxygen diffusion. Oxidation of SiC and the formation of a glassy layer has been proven to protect the sample from further oxidation, as well as provide healing of surface cracks and defects as revealed by SEM analysis. [ABSTRACT FROM AUTHOR]

This work reports the design and manufacturing of a new electrochemical sensing platform for the monitoring of prednisolone (PE) steroid in physiological fluids. To reach this, palladium (Pd) nanoparticles were successfully deposited on carbon nitride (CN) nanosheets using chemical reduction approach. The prepared CN-Pd hybrid material along with an ionic liquid (IL, 1-ethyl-3-methylimidazolium tetrafluoroborate) were employed for modification of a low expense carbon paste electrode (CPE). The CN-Pd-IL modified CPE was electrochemically characterized to ensure the electrochemical performance towards PE reduction. The important parameters affecting the performance of the PE sensor including CN-Pd dosage and pH of buffer were studied and optimized. The CN-Pd-IL modified CPE illustrated a wide linear response in a PE concentration range of 0.6 nM to 60 nM using SWV methodology. The limit of detection (based on S/N=3) was 0.1 nM at optimal conditions. The suggested PE sensor illustrated the satisfactory reproducibility and good matrix-effectless character. In addition, the CN-Pd-IL modified CPE was facilely used for the electrochemical measuring of PE in the serum samples of athletes with high recovery values (97.6%-102.4%). The proposed methodology can be employed for the sensitive, selective and fast detection of PE. [Display omitted] • Novel electrochemical sensing platform for voltammetric screening of prednisolone was proposed. • The suggested sensor illustrated the matrix-effectless character with admissible reproducibility. • The modified electrode was successfully utilized for prednisolone analysis in serum samples of athletes. [ABSTRACT FROM AUTHOR]

• The review emphasizes the potential of Mg alloys in lightweight structures and the evolution of FSP for Mg alloys and MMCs in the 21st century. • It covers novel fabrication methods, reinforcement strategies, machine and tool design parameters, material characterization, and integration with other methods for enhanced properties. • FSP offers simultaneous refinement, homogenization, and densification of microstructures, resulting in high strength and improved surface characteristics. • Challenges include the need for further study on pin profiles, process parameters, and mono and hybrid composites. It is recommended that future research should focus on material flow and reinforcement impact on temperature distribution, among many more. • Despite challenges, FSP has the potential to enhance Mg alloys and MMCs in engineering applications, presenting ongoing progress and potential advancements. Rising concerns about climate change drive the demand for lightweight components. Magnesium (Mg) alloys are highly valued for their low weight, making them increasingly important in various industries. Researchers focusing on enhancing the characteristics of Mg alloys and developing their Metal Matrix Composites (MMCs) have gained significant attention worldwide over the past decade, driven by the global shift towards lightweight materials. Friction Stir Processing (FSP) has emerged as a promising technique to enhance the properties of Mg alloys and produce Mg-MMCs. Initially, FSP adapted to refine grain size from the micro to the nano level and accelerated the development of MMCs due to its solid-state nature and the synergistic effects of microstructure refinement and reinforcement, improving strength, hardness, ductility, wear resistance, corrosion resistance, and fatigue strength. However, producing defect-free and sound FSPed Mg and Mg-MMCs requires addressing several variables and their interdependencies, which opens up a broad range of practical applications. Despite existing reviews on individual FSP of Mg, its alloys, and MMCs, an attempt has been made to analyze the latest research on these three aspects collectively to enhance the understanding, application, and effectiveness of FSP for Mg and its derivatives. This review article discusses the literature, classifies the importance of Mg alloys, provides a historical background, and explores developments and potential applications of FSPed Mg alloys. It focuses on novel fabrication methods, reinforcement strategies, machine and tool design parameters, material characterization, and integration with other methods for enhanced properties. The influence of process parameters and the emergence of defects are examined, along with specific applications in mono and hybrid composites and their microstructure evolution. The study identifies promising reinforcement materials and highlights research gaps in FSP for Mg alloys and MMCs production. It concludes with significant recommendations for further exploration, reflecting ongoing advancements in this field. [Display omitted] [ABSTRACT FROM AUTHOR]

• A novel electron-transfer MOF material was synthesized and deposited onto the porous coating of AZ31Mg alloy. This material was modified by transition metallic oxides. • The electronic structures of SnOF, ZnOF, and VOF complexes varied, impacting the morphologies of the samples and influencing their electrochemical and photocatalytic activities. • SnOF aggregation on the PEO layer sealed structural defects, creating a barrier against corrosive ion infiltration and resulting in high electrochemical stability. • SnOF and VOF samples showed high efficiency in crystal violet degradation after exposure to visible light. VOF demonstrated remarkable efficiency and stability, surpassing the performance of previously reported catalysts. • The degradation mechanism and the interaction between crystal violet and the catalyst were thoroughly examined, along with the reactive species responsible for degradation. In the pursuit of multifunctional coatings, the controlled growth of materials on stationary platforms holds paramount importance for achieving superior corrosion protection and optimal photocatalytic performance. This study introduces a cutting-edge approach, intertwining bifunctional metal-organic frameworks (MOFs) seamlessly into defective MgO layers produced by the anodic oxidation of AZ31 alloy. Key metallic oxides of Zn, Sn, and V take center stage as metallic sources for MOF formation, complemented by the organic prowess of l -Tryptophan as an α-amino acid linker. Leveraging the electronic structure of metallic oxides reacting with tryptophan molecules, controlled morphologies with distinct characteristics are induced on the defective surface of the MgO layer, enabling the precise modulation of surface defects. The hybrid composite demonstrates an adaptive microstructure in diverse aqueous environments, offering dual functionality with electrochemical stability and visible light photocatalytic activity for crystal violet degradation. Among the samples, the SnOF complex exhibited remarkable electrochemical stability with a low corrosion current density of 7.50 × 10−10 A·cm−2, along with a 94.56 % degradation efficiency after 90 min under visible light exposure. The VOF complex, under similar visible light conditions, demonstrated exceptional performance with a higher degradation efficiency of 97.79 % and excellent electrochemical stability characterized by a corrosion current density of 3.26 × 10−9 A·cm−2. Additionally, Density Functional Theory (DFT) computations shed light on the basic bonding patterns between MOFs and inorganic components, providing electronic understanding of their electrochemical and photocatalytic activities. [Display omitted] [ABSTRACT FROM AUTHOR]

Ethylenediamine-bisborane (EDB), with its high hydrogen storage capacity, has been in the limelight among researchers. In this study, a new catalytic hybrid material (Pd@ r GO-SO 3 H), comprising sulfonated reduced graphene oxide (r GO-SO 3 H) and palladium (Pd), was developed. This material serves as a highly efficient and reusable catalyst in the hydrogen production from EDB hydrolysis. The synthesized EDB, r GO-SO 3 H, and Pd@ r GO-SO 3 H were characterized using ICP-OES, PXRD, XPS, SEM, TEM, and TEM/EDX tools. The initial TOF value of the Pd@ r GO-SO 3 H catalyst in hydrogen production from EDB hydrolysis was calculated as 136 min−1. This TOF value was found to be remarkably high compared to related studies in the literature. The reusability performance of Pd@ r GO-SO 3 H was observed to be quite stable. Finally, activation parameters, such as activation energy (E a), activation enthalpy (ΔH # ), and activation entropy (ΔS # ) for the hydrolysis reaction, were calculated by conducting catalytic reactions at different temperatures using relevant equations. • R GO–SO 3 H–supported Pd NPs were prepared by easy and reproducible way. • Pd NPs in the Pd@ r GO-SO 3 H catalyst system have a mean size of 2.20 nm. • R GO–SO 3 H–supported Pd NPs were tested as catalyst for the hydrolysis of EDB. • Activity of the catalyst is 136 min−1 for EDB hydrolysis at 298 K. • R GO–SO 3 H–supported Pd NPs could be recycled for at least twenty runs. [ABSTRACT FROM AUTHOR]

Graphene-based hybrids such as carbon nanotube/graphene nanosheet (CNT/GNS), carbon nanofiber/graphene nanosheet (CNF/GNS), and CNF-CNT/GNS have attracted extensive attention in energy-related applications due to their excellent properties. The selective synthesis of GNS-based hybrids usually relies on the precise design of metal catalysts and multiple tedious processes. Here, a facile one-step synthesis of GNS-based hybrids was successfully performed by chemical vapor deposition (CVD) on waste bio-shell derived catalysts without the addition of extra metal components, and GNS-based hybrids were selectively synthesized through the hydration and dehydration (H-D) treatment of catalysts. When eggshells were calcined at high temperature, the obtained E-CaO catalyst only synthesized GNSs. After E-CaO was treated by the H-D method, the obtained E-CaO-H-1 catalyst grew CNF/GNS. E-CaO-H-2 catalyst was further prepared by the H-D treatment of E-CaO-H-1, which produced CNF-CNT/GNS. Multiple characterizations of catalysts demonstrated that the high-temperature calcination of eggshells led to the aggregation of CaO and incorporation of Fe into CaO lattices, and thus only GNSs were synthesized on CaO. However, after the H-D treatment of E-CaO, the Fe element was released from CaO lattices and the surface area of CaO enhanced with the decrease of particle size, leading to the dispersion of Fe oxides on the CaO surface, and Fe particles were subsequently formed during the CVD synthesis, which synthesized CNFs on GNS. Further, with the size reduction of Fe particles after the second H-D treatment of the catalyst, smaller Fe particles facilitated the CNT growth, leading to the production of CNF-CNT/GNS. Similarly, the catalysts formed by calcination of other bio-shells (oyster shells, shrimp shells, and crab shells) only synthesized GNSs, whereas these catalysts after H-D treatment produced CNF-CNT/GNS with enhanced carbon yields. This study offers a new method for utilizing the metal species in waste bio-shells for the facile production of structurally tunable GNS-based hybrid materials. [ABSTRACT FROM AUTHOR]

The current work investigates the effects of drilling parameters on hole quality, including delamination and circularity, produced in hybrid composite materials consisting of neat glass fibre (NG) and hybrid glass fibre/Al-wire mesh in two distinct sequences, the first one being with Al-mesh in the outermost layers (AG) and the other with Al-mesh in the central layer (GA). The operation's process parameters are feed rate (F = 20, 40, and 60 mm/min), spindle speed (N = 1000, 2000, and 3000 rpm), and drill point angle (Ɵ = 90°, 120°, and 135°). Taguchi's L9 orthogonal array is used for the study. The optimal levels and effects of the process parameters were determined. Gray relational analysis (GRA) was employed to examine the complicated interactions influencing the results and ANOVA was used to evaluate the influence of process parameters. The results indicated that for all specimens, push-out delamination was more severe than peel-up. Circularity is minimized by using N = 3000 rpm, F = 20 mm/min, and Ɵ = 90°. At speed (N) of 3000 rpm circularity reduces by 83.5% and 76.5% compared to 1000 or 2000 rpm, respectively. Compared to other specimens, AG-specimen produced minimal delamination and circularity by an average of 6% and17.38%. The results of the confirmation test and regression model provide good agreement between the experimental and predicted results. [ABSTRACT FROM AUTHOR]

Low-temperature and short-time sinter-forging has been used to obtain a dense WC/Y–TZP–Al 2 O 3 hybrid ceramic–matrix composite with dispersed Hadfield steel with high fracture toughness. The hardness and К 1С fracture toughness were 13.7 ± 0.3 GPa and 7.4 ± 0.4 MPa m1/2, respectively. The composite contained phases such as Y–TZP–Al 2 O 3 eutectics and hypereutectic grains, WC agglomerates, γ-Fe particles as well as small amounts of Al 2 (WO 4) 3 and MnFe 2 O 4. No t -ZrO 2 →m-ZrO 2 transformational toughening occurred during mechanical loading so that enhanced fracture toughness resulted from forming a dense microstructures with ductile metallic interlayers between ceramic and tungsten carbide grains. [ABSTRACT FROM AUTHOR]

Amorphous CoO/Al 2 O 3 /C hybrids were synthesized using a simple pyrolysis method at various temperatures and reagent ratios. At 500 °C, CoO localized from homogenous distribution to quantum dots (∼10 nm) on the Al 2 O 3 /C matrix. X-ray photoelectron spectroscopy results suggested that the feed nitrate ions doped the hybrids with pyridinic (398.8 eV) and pyrrolic (400.55 eV) N, which ameliorated the electrochemical performance of the hybrids. The optimum pyrolysis temperature to obtain a reversible capacity of 0.45 Ah g−1 at the 1000th cycle at a current density of 1 A g−1 was 500 °C. However, owing to the polarization electrode, the specific capacity decreased by 54 % after increasing the material mass loading (0.5–3 mg cm−2), which resulted in a maximum areal capacity of 0.78 mAh cm−2. After regulating the C content in the hybrid, the loss in reversible capacity was only 29 % for an eight-fold gain in the mass-loading (0.4–3.2 mg cm−2) and the areal capacity was up to 1.13 mAh cm−2. The specific capacity of the optimized electrode was 0.52 Ah g−1 at the 1000th cycle. In addition, it only lost 28 % of its capacity along with a ten-fold increase in current density (0.2–2 A g−1). In a full cell test involving a LiNi 0.8 Mn 0.1 Co 0.1 O 2 -based cathode and a CoO/Al 2 O 3 /C-based anode, 91 % of the maximum theoretical specific capacity was obtained, whereas the capacity retention at the 100th cycle was 97 %. Electrochemical impedance spectra suggested that small resistances (<38 Ω) and high Li+ diffusivity (5.5–6.8 × 10−11 cm2 s−1) supported the fast-charging properties of the hybrid. [Display omitted] • Pyrolysis temperature affects CoO/Al 2 O 3 /C hybrid's cyclability via CoO's distribution. • Increasing C content in the hybrid improves electrode's polarization. • Current density, capacity balance, and electrolyte affects a full-cell's performance. [ABSTRACT FROM AUTHOR]

Nanoscale coordination polymer (NCP) is a class of hybrid materials formed by self-assembly of metal ions and organic ligands through coordination. The applications of NCP in biomedicine are quite extensive due to the diversity choice of metal ions and organic ligands. Here we designed Zr-P1 NCP based on Zr4+ selected as metal ion nodes and tetrakis(4-carboxyphenyl) ethylene as bridging ligands. Zr-P1 NCP was modified with functionalized pyrene derived polyethylene glycol (Py-PAA-PEG-Mal) on the surface and further conjugated with cRGD for active targeting of integrin α v β 3 overexpressed in triple-negative breast cancer. Doxorubicin was loaded on Zr-P1 NCP with encapsulation efficiency up to 22 % for the treatment of triple negative breast cancer. 89Zr-P1 NCP can be used for in vivo tumor imaging due to the fluorescence properties resulting from the enhanced aggregation-induced Emission (AIE) behavior of P1 ligands and its positron emission tomography (PET) capability. Cellular evaluation indicated that the functionalized Zr-P1@PEG-RGD presented a good function for tumor cell targeting imaging and doxorubicin could be targeted to triple negative breast cancer when it was loaded onto Zr-P1@PEG-RGD, which corroborated with the in vivo results. In summary, 89Zr-P1@PEG-RGD can serve as a biocompatible nanoplatform for fluorescence and PET image-guided cargo delivery. Nanoscale coordination polymer (NCP) is a class of hybrid materials formed by self-assembly of metal ions and organic ligands through coordination. The diversity of available metals and ligand structures upon NCP synthesis plays an advantage in establishing multimodal imaging platforms. Here we designed 89Zr-P1@PEG-RGD NCP based on Zr4+ selected as metal ion nodes and tetrakis(4-carboxyphenyl) ethylene as bridging ligands. 89Zr-P1@PEG-RGD nanomaterials have positron emission tomography (PET) capability due to the incorporation of zirconium-89, which can be used for in vivo tumor imaging with high sensitivity. The chemotherapeutic drug DOX was loaded on Zr-P1 NCP for the treatment of triple-negative breast cancer, and dual modality imaging can provide visual guidance for drug delivery. [Display omitted] [ABSTRACT FROM AUTHOR]

In this research, a chronoamperometric biosensor based on zinc oxide (ZnO)-graphene oxide (GO) nanocomposite material was designed and employed for lactate determination. The ZnO-GO hybrid proved to be a suitable substrate for the immobilization of lactate oxidase (LOD). The presence of ZnO and GO components in hybrid material led to synergistic effects and facilitates the LOD loading and electron transfer between the receptor and screen printed carbon electrode (SPCE) surface. The LOD-GO-ZnO modified SCPE exhibits excellent lactate sensing capabilities thanks to the uniform dispersion of ultrafine ZnO nanoparticles and enhanced mass-transfer kinetics. In phosphate buffer solution (pH=7.4), this novel electrochemical lactate biosensor demonstrates a linear response to lactate within the concentration range of 0.015–1.25 mM. Limit of detection (based on S/N=3) of the assay was estimated to be 9 µM. More importantly, the presence method is a highly selective device for the analysis of lactate in biological fluids. The lactate level in saliva samples was successfully measured before and after exercise of athletes using the suggested biosensor. This method offers a simple, cost-effective, fast, and effective platform for lactate determination in typical diagnostic applications. [Display omitted] • Using ZnO-GO nanocomposite, a navel biosensor for lactate detection was manufactured. • The proposed sensing strategy shows low detection limit towards lactate. • The biosensor was successfully employed for lactate determination in biological fluids. [ABSTRACT FROM AUTHOR]

The preparation of low-cost and high-activated catalysts is an important challenge in the development of hydrogen production industry. Here we reported a novel core-shell triangular cone electrocatalyst Ni 3 S 2 @Ni 3 N@Co 2 N 0.67 grown on nickel foam (Ni 3 S 2 @NiCoN/NF) obtained by a self-templated method. The obtained Ni 3 S 2 @NiCoN/NF consists of Ni 3 S 2 triangular cone core and Ni 3 N@Co 2 N 0.67 particles shell, which has rich heterogeneous interface and synergistic effect. The strong electronic interaction at the newly bonded heterojunction regulates the electronic structure of active Ni, which is conducive to the transfer of charge to the active site. In addition, NiCoN particles are coated on the surface of Ni 3 S 2 triangular pyramidal nucleus to form a core-shell structure, which can make sure the exposure of active sites. It is found that the self-templated conversion of Co(OH) 2 coated Ni 3 S 2 into NiCoN/Ni 3 S 2 enhances the activity for hydrogen evolution reaction (HER). The hybrid material has excellent HER catalytic performance under alkaline conditions, which only needs to overcome the overpotential of 63 and 174 mV to reach the current density of 10 and 100 mA cm−2, respectively. This study provides a new idea for the preparation of efficient and stable catalysts with core-shell structure for HER. • Novel Ni 3 S 2 @NiCoN for HER has been prepared by a self-templated method. • The core-shell structure with heterogeneous interface enhances the conductivity. • The typical structure and proper component contribute to the electrochemical activity. [ABSTRACT FROM AUTHOR]

[Display omitted] Metalenses have outstanding light-modulating performances, and studies have been conducted on them to not only replace conventional bulky and heavy refractive lenses but also to expand on them. However, their operating wavelengths have rarely covered the ultraviolet (UV) regime since UV-transparent materials are scarce and nanopatterning techniques have a small patterning area, high cost, and low throughput. These limitations are overcome in this study, and centimeter-scale and highly efficient UV metalenses are successfully mass-produced. The UV metalens is designed to operate at a wavelength of 325 nm, with a numerical aperture of 0.2. Argon fluoride photolithography is used to fabricate an 8-inch master stamp in which 300 metalenses are patterned in an array with a high resolution. The fabricated master stamp can be duplicated repeatedly using wafer-scale nanoimprint lithography. To improve efficiency, we developed a zirconium dioxide–polymer hybrid material that is scalable, easily manufacturable, UV-transparent, and high-index material. The experimental results confirm that the mass-produced metalenses operate as ideal imaging systems, exhibiting an average measured efficiency of 45.1 %. [ABSTRACT FROM AUTHOR]

[Display omitted] Interconnected porous materials have recently emerged as hybrid porous materials, comprising (meso/micro)pores with interconnected (micro/meso)porous walls. Benefiting from structural, morphological, and geometrical properties, interconnected porous materials are endowed with high porosity, specific surface area, mass transfer capacity, tailored pore sizes, volume and shape compatibility. These hybrid materials can be synthesized and further functionalized into a wide range of nanomaterials by either modifying conventional strategies or involving novel strategies such as pillared-layer assembly, defect-formation and/or the use of structure-directing agents. Owing to their exceptional properties, functionalized materials have already exhibited remarkable potential in various practical applications including reduction, sensing, purification, detection of gases, harvesting, conversion, and storage of energy, photocatalysis, electrocatalysis, chemical synthesis, as well as non-automotive applications. A brief description of recent advancements in catalysis and energy conversion/storage applications of functionalized interconnected materials as well as prospects is provided in this contribution. [ABSTRACT FROM AUTHOR]

Herein, CuCo 2 O 4 nanocomposites were synthesized using a facile electrochemical method and a subsequent annealing treatment. Afterward, uniform Pd nanoparticles were further doped on the surface of CuCo 2 O 4 via an electrochemical deposition. Gas-sensing tests showed that this novel Pd@CuCo 2 O 4 hybrid exhibited a relatively high response of 17 % and a short response time of 150 s. The response of the film to hydrogen gas was measured at flow values of 500 and 1000 ppm at 300 °C. Pd@CuCo 2 O 4 shows 17 %, CuCo 2 O 4 shows 16 % response to 1000 ppm, Pd@CuCo 2 O 4 shows 11 %, CuCo 2 O 4 shows 9 % response to 500 ppm H 2 gas. Furthermore, Pd@CuCo 2 O 4 /n-Si and CuCo 2 O 4 /n-Si devices were fabricated as a photodetector. I–V measurements were performed under both visible light and UV light (365 and 395 nm) to test the optical performance of both devices. The Pd@CuCo 2 O 4 /n-Si exhibited better optical performance than the undoped device, and this was attributed to the increase in the conductivity of the material by Pd doping. The results indicated that Pd@CuCo 2 O 4 hybrid composites are a promising material for monitoring and accurately detecting H 2. [Display omitted] [ABSTRACT FROM AUTHOR]

• SiC incorporation in a Mg 2 Si matrix for improving wear resistance during additive manufacturing. • Localization of secondary phase along the edge of each melt pool of the primary phase. • Formation of a compositional gradient distribution from the center to the edge of each melt pool of the Mg 2 Si–SiC/nitride hybrid composite. • Yield strength of the aged Mg 2 Si–SiC/nitride hybrid composite after longitudinal additive manufacturing was 559.6 MPa. • Discovery of a new type of hybrid composite with a build-direction-dependent functionally graded structure. The ex-situ incorporation of the secondary SiC reinforcement, along with the in-situ incorporation of the tertiary and quaternary Mg 3 N 2 and Si 3 N 4 phases, in the primary matrix of Mg 2 Si is employed in order to provide ultimate wear resistance based on the laser-irradiation-induced inclusion of N 2 gas during laser powder bed fusion. This is substantialized based on both the thermal diffusion- and chemical reaction-based metallurgy of the Mg 2 Si–SiC/nitride hybrid composite. This study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-dependent architectonics during additive manufacturing. This strategy enables the development of a compositional gradient from the center to the edge of each melt pool of the Mg 2 Si–SiC/nitride hybrid composite. Consequently, the coefficient of friction of the hybrid composite exhibits a 309.3% decrease to –1.67 compared to –0.54 for the conventional nonreinforced Mg 2 Si structure, while the tensile strength exhibits a 171.3% increase to 831.5 MPa compared to 485.3 MPa for the conventional structure. This outstanding mechanical behavior is due to the (1) the complementary and synergistic reinforcement effects of the SiC and nitride compounds, each of which possesses an intrinsically high hardness, and (2) the strong adhesion of these compounds to the Mg 2 Si matrix despite their small sizes and low concentrations. [ABSTRACT FROM AUTHOR]

• A novel approach to high-performance hybrid materials for corrosion prevention. • WO 3 /PPVA hybrids deposited in a fragmented manner, forming a "laminar reef-like structure. • PPVA-sealed WO 3 -based coating showed superior corrosion resistance compared to other samples. • Computational analyses to elucidate the hybrid formation mechanism. Meeting the demands of complex and advanced applications requires the development of high-performance hybrid materials with unique properties. However, the integration of polymeric frameworks with MgO/WO 3 composite layers faces challenges due to the lack of understanding of the formation mechanism and the challenge of determining the impact of self-assembled architecture on anticorrosive properties. In this study, we aimed to enhance the corrosion resistance of the MgO layer produced by plasma electrolysis (PE) of AZ31 Mg alloy by incorporating WO 3 with partially phosphorated poly(vinyl alcohol) (PPVA). Two types of porous MgO layers were produced using the PE process with an alkaline-phosphate electrolyte, one with and one without WO 3 nanoparticles, which were subsequently immersed in an aqueous solution of PPVA. Incorporating PPVA into the WO 3 -MgO layer resulted in hybrids being deposited in a fragmented manner, creating a '' laminar reef-like structure '' that sealed most of the structural defects in the layer. The PPVA-sealed WO 3 -based coating exhibited superior corrosion resistance compared to the other samples. Computational analyses were employed to explore the mechanism underlying the formation of PPVA/WO 3 hybrids on the MgO layer. These findings suggest that PPVA-WO 3 -MgO hybrid coatings can potentially improve corrosion resistance in various fields. [ABSTRACT FROM AUTHOR]

Motivated by the unique structures and diverse properties of two-dimensional (2D) heterostructures, herein, we designed a series of heterojunction-based catalysts composed of MoS 2 and M 2 CO 2 monolayers (M = Ti, V, Cr, Zr, Nb, Mo, Hf, and Ta) monolayers, and investigated their activities towards HER by means of density functional theory (DFT) computations. The results showed that these van der Waals heterostructures exhibit favorable stability, high stiffness, and versatile electronic properties. Interestingly, MoS 2 /Nb 2 CO 2 and MoS 2 /Ta 2 CO 2 candidates were expected to exhibit high HER catalytic activity at low H coverage due to their optimal H* adsorption strength, and the low barrier for H 2 release via the Heyrovsky mechanism. More importantly, we for the first time proposed that the difference in the work functions between MoS 2 and M 2 CO 2 can be utilized as an ideal descriptor to rationalize the remarkably different HER catalytic activity of these MoS 2 /M 2 CO 2 hybrid materials. This work not only suggested efficient catalysts for advancing sustainable H 2 production, but also opened a new door to further explore the potential of 2D heterostructures in electrocatalysis. • The MoS 2 /M 2 CO 2 heterostructures exhibit good stability and diverse properties. • MoS 2 /Nb 2 CO 2 and MoS 2 /Ta 2 CO 2 candidates display high HER catalytic activity. • The HER process can take place via the Heyrovsky mechanism. • The difference in the work functions between MoS 2 and M 2 CO 2 determines the HER activity of MoS 2 /M 2 CO 2 heterostructures. [ABSTRACT FROM AUTHOR]

The simultaneous degradation of organic pollutants and generation of value-added compounds like ammonia and hydrogen energy has recently gained considerable attention in photocatalysis. The present study deals with successful preparation of novel AgVO 3 nanowire@rGO-tetrahedral Ag 3 PO 4 (110) (AGA) heterojunction and utilized for enhanced generation of NH 3 and H 2 from N-containing antibiotic sulfamethoxazole (SMX) under visible light. The prepared catalyst was well characterized by XRD, SEM, TEM and XPS to confirm the formation of heterojunction. The results indicated that the composite exhibited 546.0 μmol g−1 of hydrogen evolution rate, which is approximately 3.6 (153.6 μmol g−1) and 5.1 (108.7 μmol g−1) times higher than the pure AgVO 3 and Ag 3 PO 4 respectively after 6 h. Similarly, 38.3 mg L−1g−1 of NH 3 generation was observed during 6 h of SMX degradation, which is about 1.9 and 2.8 times higher than the pure AgVO 3 (20.1 mg L−1g−1) and Ag 3 PO 4 (13.7 mg L−1g−1) respectively. The formation of heterojunction between AgVO 3 and Ag 3 PO 4 not only promotes the transfer of electron but also prevents the recombination which eventually enhances the catalytic conversion of N-element to NH 3 and for H 2 generation during water splitting. Furthermore, the plausible degradation pathway in SMX was proposed and the results revealed that the SMX was mineralized by the composite further converted to NH 3 and generates H 2 during the degradation process. Thus, our study provides new insights into novel photocatalytic treatment methodologies for simultaneous degradation of SMX to produce NH 3 and H 2 as value-added compounds from antibiotic wastewaters during water treatment process. • A facile dual functional hybrid composite was prepared. • H 2 and NH 3 has been generated during photocatalytic degradation of SMX. • Heterojunction significantly enhanced SMX degradation and H 2 generation. • N-containing SMX molecule was utilized as a nitrogen source for ammonia. [ABSTRACT FROM AUTHOR]

Energy efficient buildings, propulsion components and thermal protection systems require materials with high thermal protective properties. Traditional polymer composites or ceramic materials have limited comprehensive applications because of their poor thermal protective properties or poor processability. Herein, a novel fire resistant and thermally insulating polymer/ceramic hybrid ceramifiable composite was developed based on low temperature sintering principle and foaming on fire strategy. Specifically, the influences of raw materials of low temperature ceramics, such as glass frit, phosphate, etc, on the properties of ceramifiable ethylene-vinyl acetate (EVA) composites were investigated. Its fire resistance and thermal insulation properties were evaluated by simulating different sintering environments. The results show that the ceramifiable composite exhibits the highest improvement in fire resistance because a crystalline phase was formed at high temperatures. Gas evolution from the thermal decomposition of ammonium polyphosphate (APP) and EVA contributes to the formation of the porous structure in ceramic residues. The optimal system can resist above 1000 °C flame for 30 min without disintegration, and the temperature of the unfired side was maintained around 200 °C. The reliability of the strategy was verified by the effective medium theory model. [Display omitted] [ABSTRACT FROM AUTHOR]

Investigate attrition simulation using CAD/CAM leucite-reinforced glass-ceramic antagonists on occlusal vs. buccal enamel. Three dental materials with known wear rates (resin-modified glass-ionomer, micro-filled, and fine particle composites) validated the wear simulator (CAD/CAM glass-ceramic antagonists, 200 cycles, 80 N load, deionised water irrigation, 0.7 mm sliding movement). Following this, human molars were sectioned into paired occlusal and buccal polished samples (n = 8/gp). Exposed 1.5 mm Ø enamel areas were subjected to attritional wear with and without pre-immersion in citric acid (5 min, 0.3%, pH 3.8). Profilometry measured step-height enamel wear and surface microhardness at different depths was calculated using Vickers indentation at 0.1 N and 0.5 N loads. Dental material wear using the CAD/CAM antagonists showed consistency with previous data: mean (SD) resin-modified glass ionomer material loss of 177.77 (16.89) µm vs. 22.15 (1.30) µm fine particle hybrid composite resin wear vs. 13.63 (1.02) µm micro filled composite resin wear (P < 0.001). The coefficient of variation was less than 10%. Following validation, enamel sample wear was significantly increased when attrition was introduced (P < 0.001) independent of buccal vs. occlusal sample location (P < 0.05). Attrition resulted in occlusal wear of 26.1 ± 4.5 µm vs. buccal 26.3 ± 1.2 µm and attrition/erosion resulted in occlusal wear of 26.05 ± 4.46 µm vs. buccal 25.27 ± 1.16 µm. Whereas erosion-alone resulted in occlusal wear of 1.65 ± 0.13 µm and buccal 1.75 ± 0.03 µm. Microhardness testing at different loads revealed significantly greater hardness reductions in occlusal enamel vs. buccal enamel for 0.1 KgF indentations (P < 0.001) whereas in contrast 0.5 KgF indentations showed no differences. Wear simulation with CAD/CAM glass ceramic antagonists produced consistent wear in dental materials and human enamel, regardless of enamel surface origin. Lighter (0.1 KgF) hardness testing of occlusal vs. buccal origin revealed damage to the mechanical integrity of the superficial worn enamel. • Valid attritional wear simulation requires a co-efficient of variation ∼10%. • CAD/CAM leucite-reinforced glass-ceramic antagonists can simulate attrition. • Occlusal and buccal polished enamel samples wear at similar rates in vitro. • Attrition results in subsurface damage of human enamel due to mechanical wear. [ABSTRACT FROM AUTHOR]

Green hydrogen production by water electrolysis with the least possible energy waste requires the application of suitable electrocatalytic electrodes. In this work, highly active, free-standing electrodes were prepared by deposition of nitrogen-doped carbon nanofibers (N-CNFs) on oxidized carbon cloth. Different types of N-CNFs with variable structures, nitrogen dopant concentrations and defect contents were synthesized. Their electrocatalytic activities as hybrids with oxidized and raw carbon cloth electrodes were evaluated in the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). We show that the N–CNF sample with the highest nitrogen doping in the series (6.7 at.%) and the predominance of well-ordered herringbone/bamboo-like structure with abundant edge sites, exhibited both the highest OER and HER activities (with overpotentials of 330 and 410 mV, respectively at j = ±10 mA cm−2) and excellent performance stability. The hybrid material provided abundant active sites on N-CNFs that show good adhesion to the hydrophilic carbon cloth. • Herringbone/bamboo-like N-doped CNFs exhibit exceptional electrocatalytic activity. • The N–CNF composite with carbon cloth shows OER η 10 = 330 mV and HER η -10 = 410 mV. • This structure provides high electrochemically active surface area. • The material activity in HER correlates with the nitrogen dopant concentration in the N-CNFs. • The OER activity is based on electrocatalytically active spots located in the mesopores. [ABSTRACT FROM AUTHOR]

Amorphous molybdenum sulfide (a-MoS 3) is a promising non-precious electrocatalyst for hydrogen evolution reaction owing to the abundant defective active sites. Here in, we show a rapid microwave-assisted synthesis method to produce a-MoS 3 catalysts on reduced graphene oxide (rGO) substrates. The a-MoS 3 reported in this study comprise of two possible 1D chain-like structures, i.e., with molybdenum (IV) in Weber's model and molybdenum (V) in Hibble's model, unlike the polymeric cluster type a-MoS 3 structures reported in literature. Thermal annealing of the microwave-prepared a-MoS 3 produced a family of defect-engineered MoS x /rGO hybrids, from a-MoS 3 to crystalline MoS 2 , which showed tunable HER activities. XPS analysis provided in-depth understanding of the compositional changes in MoS x /rGO with thermal annealing. The a-MoS 3 /rGO 250 (annealed at 250 °C) exhibited the highest HER catalytic activity among all the MoS x /rGO hybrids, with an overpotential of 208 mV at 10 mA/cm2, a low Tafel slope of 52 mV/decade, a high double layer capacitance of 3.7 mF/cm2 and a high TOF value of 0.43 H 2 /s per site at the HER overpotential of 208 mV. The excellent HER activity is attributed to both MoV and sulfur active sites. This study provides a controllable, scalable and rapid synthesis method to produce 1D chain-like a-MoS 3 structures for HER electrocatalysis. 1D chain-like amorphous molybdenum trisulfide was deposited on reduced graphene oxide (a-MoS 3 /rGO) via a microwave-assisted synthesis. Further thermal annealing resulted in a series of defect engineered MoS x /rGO hybrids with tunable composition and HER activity. The a-MoS 3 /rGO annealed at 250 °C exhibits excellent HER electrocatalytic activity and stability. [Display omitted] • Rapid microwave-assisted synthesis of 1D chain-like amorphous MoS 3 on rGO. • Subsequent thermal annealing of a-MoS 3 produces defect-engineered MoS x /rGO hybrids. • XPS reveals the tunability in composition of hybrids by annealing, from amorphous MoS 3 /rGO to crystalline MoS 2 /rGO. • The amorphous MoS 3 /rGO annealed at 250 °C exhibits the highest HER overpotential of 208 mV at 10 mA/cm2 with remarkable stability. • Both Mo and S act as HER catalytic active sites. [ABSTRACT FROM AUTHOR]

It is important to develop new metal-free catalysts that are both low-cost and environmentally friendly with high performance. Recently, heterojunction catalysts have been used more than single-component catalysts in catalytic reactions. The current study reports the facile production of a new environmental and green metal-free nanocatalyst by three stages including the synthesis of graphite carbon nitride (GCN) from urea, synthesis of GCN-γ-Al 2 O 3 hybrid composite from GCN and aluminium oxide (γ-Al 2 O 3), and synthesis of O-doped GCN-γ-Al 2 O 3 from the interaction of hybrid GCN-γ-Al 2 O 3 with nitric acid treatment. The obtained O-doped GCN-γ-Al 2 O 3 hybrid material was used to catalyse the green and environmental H 2 production(H 2 -P) from sodium borohydride (NaBH 4) methanolysis for the first time. The chemical compositions and morphology structures of these heterojunction-structured hybrid catalysts were carefully characterized by SEM-EDS, XRD, FTIR, TEM, and XPS analyses, and the catalytic activities and reusability were systematically evaluated. The H 2 generation rate (HGR) values of GCN, GCN-γ-Al 2 O 3 and O doped GCN-γ-Al 2 O 3 catalysts were found as 3486, 5310 and 10080 ml min-1 g-1, respectively. The activation energy (Ea) for the O-doped GCN-γ-Al 2 O 3 catalyst was 35.12 kJ mol-1. Besides, the mechanism of the O-doped GCN-γ-Al 2 O 3 catalyst in the NaBH 4 methanolysis reaction(NaBH 4 -RM) was tried to be clarified. [Display omitted] • O doped GCN-γ-Al 2 O 3 was used for H 2 production from NaBH 4 methanolysis. • HGR values of GCN-γ-Al 2 O 3 and O doped GCN-γ-Al 2 O 3 were 5310 and 10080 ml min-1 g-1. • The activation energy for the O doped GCN-γ-Al 2 O 3 catalyst was 35.12 kJ mol-1. • XRD, SEM-EDS, TEM, FTIR and XPS analyses were used for characterization. [ABSTRACT FROM AUTHOR]