High Structural Integrity Research Articles

Thermoresponsive Gels with Rosemary Essential Oil: A Novel Topical Carrier for Antimicrobial Therapy and Drug Delivery Applications

This study investigates the development and comprehensive characterization of innovative thermoresponsive gels incorporating rosemary essential oil (RoEO) encapsulated in poly(lactic-co-glycolic acid) (PLGA) microparticles, with a focus on their potential applications in topical antimicrobial and wound healing therapies. RoEO, renowned for its robust antimicrobial, antioxidant, and wound-healing properties, was subjected to detailed chemical profiling using gas chromatography-mass spectrometry (GC–MS), which identified oxygenated monoterpenes as its dominant constituents. PLGA microparticles were synthesized through an optimized oil-in-water emulsion technique, ensuring high encapsulation efficiency and structural integrity. These microparticles were thoroughly characterized using Fourier-transform infrared (FTIR) spectroscopy to confirm functional group interactions, scanning electron microscopy (SEM) for surface morphology, X-ray diffraction (XRD) for crystalline properties, and thermal analysis for stability assessment. The synthesized microparticles displayed uniform size distribution and efficient encapsulation, demonstrating compatibility with the gel matrix. Two distinct thermoresponsive gel formulations were developed using varying ratios of Poloxamer 407 and Poloxamer 188 to achieve optimal performance. The gels were evaluated for key physicochemical properties, including pH, gelation temperature, viscosity, and rheological behavior. Both formulations exhibited thermoresponsive gelation at skin-compatible temperatures (27.6 °C and 32.9 °C), favorable pH levels (6.63 and 6.40), and shear-thinning behavior suitable for topical application. Antimicrobial efficacy was assessed against common pathogens associated with skin infections, including Staphylococcus aureus, Escherichia coli, and Candida albicans. The RoEO-PLGA-loaded gels demonstrated significant inhibitory effects, confirming their potential as effective carriers for controlled and localized drug delivery. These findings underscore the promising application of RoEO-PLGA-loaded thermoresponsive gels in addressing challenges associated with topical antimicrobial therapies and wound care, offering an innovative approach to enhancing therapeutic outcomes. By integrating the bioactive potential of RoEO with the advanced delivery capabilities of PLGA microparticles and thermoresponsive gels, this study paves the way for the development of next-generation formulations tailored to meet the specific needs of localized drug delivery in skin health management.

Aqueous Binder with Self-Emulsifying Characteristics for Practical Si/C Anode in Lithium-Ion Batteries.

Silicon/carbon (Si/C) materials have achieved commercial applications as a solution to the problems of large volume expansion and short lifespan of silicon-based anodes in lithium-ion batteries. However, the potential risk of structural fracture and localized differences in surface adsorption properties lead to difficulties in maintaining the structural integrity of Si/C anodes using conventional binders during repeated lithiation/delithiation. Herein, an aqueous binder (PVA-g-M) based on polyvinyl alcohol (PVA) grafted methacrylic acid (MAA) obtained by self-emulsifyingemulsion polymerization is reported. The introduction of carboxyl groups of MAA enables PVA-g-M to form more hydrogen bonds, thereby enhancing both the cohesion of the binder film and its adhesion to silicon-based surface. Simultaneously, the methyl-containing segments of MAA can wet the carbon-based surface, thereby enhancing the adhesion of PVA-g-M to carbonaceous materials. In addition, the hydroxyl groups on both the PVA segments and the silicon surface can be esterified with the carboxyl groups during the heat treatment, thus further improving the bonding strength. As-prepared Si/C anodes with PVA-g-M binder can significantly inhibit the electrode volume expansion and maintain high structural integrity during cycling as well as form SEIs with high lithium fluoride content, showing excellent cycling stability (81.1% capacity retention after 300 cycles).

Condensation heat transfer and applicability assessment of a printed circuit heat exchanger as a condenser in a cryogenic CO2 capture and storage system

Global warming is accelerating due to the rapid increase in CO2 emissions and cold energy. CO2 capture and storage systems (CCSSs) using discarded cold energy have been suggested to prevent this problem. To utilize cold energy, a printed circuit heat exchanger (PCHE) with high structural integrity was applied as a condenser in the CCSS. However, studies on condensation heat transfer in PCHE are still lacking, and conventional condensation heat transfer correlations developed in circular-channels do not sufficiently predict heat transfer performance in PCHE. Additionally, evaluating the local heat transfer performance is difficult because PCHE is an all-in-one type heat exchanger. Therefore, in this study, a CO2 condensation experiment in PCHE was conducted using an optical fiber sensor as a measurement, which can evaluate the local heat transfer performance, and a new condensation heat transfer correlation for CO2 in PCHE was developed. The correlation was approximately 20 % smaller than the conventional correlations developed in circular-channels, indicating that CO2 would not be fully condensed if the condenser was designed by conventional correlations. Based on the developed correlation, in-house code was developed and the CCSS using cold energy was compared with the conventional CCSS, which condenses CO2 after pressurizing it to a high pressure. As a result, cold energy based CCSS could replace the conventional CCSS because the CCSS using cold energy was approximately 5.7 million-USD per year more economical than the conventional CCSS when condensing CO2 at 200 tons/h. These results contribute to the design of PCHE-type condensers used in the CCSS.

The Effect of Adhesive Quantity on Adhesion Quality and Mechanical Characteristics of Woven Kevlar Fabric-Reinforced Laminated Structures

This study investigated the adhesion and mechanical properties of woven fabric-reinforced laminates (FRLs) made with four distinct Kevlar fabrics of varying areal densities (36 g/m2, 60 g/m2, 140 g/m2, and 170 g/m2) under different fabric-to-adhesive weight ratios (1:0.5, 1:1, and 1:1.5) in both the warp and weft directions. A novel aspect of this research lies in our systematic study of the effect of adhesive quantity on FRLs, a topic that has received limited attention despite its critical role in laminate performance. Additionally, the application of a newly developed yarn pullout test alongside the standard T-peel test provides unique insights into the interfacial behavior of laminates. The results show that in lower areal density fabrics (36 g/m2 and 60 g/m2), adhesive quantity minimally affects the pullout and T-peel forces or tear strength, indicating that structural integrity can be maintained with reduced adhesive application. In contrast, higher areal density fabrics (140 g/m2 and 170 g/m2) benefit from an increased adhesive ratio, with a transition from 1:0.5 to 1:1 significantly enhancing the pullout resistance, while further increases to 1:1.5 yielded diminishing returns. Tensile strength remained consistent across all samples, highlighting that it is largely dictated by the inherent properties of the fibers and fabric structure rather than the adhesive. This study concludes that a 1:1 fiber-to-adhesive ratio offers an optimal balance of adhesion quality and mechanical performance for FRLs. By addressing the understudied impact of adhesive quantity on FRLs and introducing the yarn pullout test, this research provides novel and practical guidelines for optimizing FRLs in applications demanding high structural integrity and adaptability under challenging conditions.

A novel silicon carbide plate-fin heat exchanger and its thermal and hydraulic performance for SOFC cathode air preheater application

This paper focuses on a novel silicon carbide (SiC) plate-fin heat exchanger (PFHE) for the cathode air preheater application of Solid Oxide Fuel Cells (SOFCs). An innovative assembly method and a reliable connection structure with the system's metal pipelines were proposed, and then a prototype of the SiC PFHE with offset strip fins was developed. Additionally, a performance testing apparatus for the SOFC cathode air preheater was built. Based on this testing setup, experimental studies and application validation on the heat transfer and flow characteristics of the SiC PFHE were conducted. Finally, the application prospect of SiC PFHE in SOFC systems was further evaluated and compared with metallic plate heat exchangers. The results indicate that the assembly structure and test procedure of the SiC PFHE not only realize the reliable high temperature sealing, but also effectively reduce the thermal stress of SiC ceramic material. Essential parameters such as overall heat transfer coefficient, Colburn factor, and friction factor reveal consistent trends with existing literature under various operating conditions at average Reynolds number in the range from 84 to 361. The SiC PFHE has significant advantages in upper operating temperature limit and high temperature structural integrity and reliability.

Shock Response of Sandwich Panels with Additively Manufactured Polymer Gyroid Lattice Cores

This work evaluates the shock response of sandwich structures with gyroid lattice cores made from Polylactic Acid (PLA), Acrylonitrile Butadiene Styrene (ABS), and Thermoplastic Polyurethane (TPU) using shock tube experiments coupled with high-speed photography and digital image correlation (DIC). The study found that gyroid lattice structures exhibit high energy absorption capacity and good structural integrity under shock loading, making them suitable for high strength-to-weight ratio and energy absorption applications in aerospace and defense industries. The sandwich panel with a TPU-core structure exhibited the highest deformation under shock loading, with a maximum deflection of approximately 6mm, followed by ABS at 0.9mm and PLA at 0.82mm. Under shock loading, the sandwich panel with TPU gyroid core exhibited the highest specific deformation energy (0.146J/g), which is consistent with its flexibility, though it remained in the same general order as ABS (0.104J/g) and PLA (0.070J/g). Interestingly, the specific total energy of the TPU gyroid core sandwich, while the lowest at 39.310J/g, was still relatively close to ABS (54.098J/g) and PLA (52.620J/g), despite the substantial difference in inherent stiffness of TPU compared to ABS and PLA. This suggests that while TPU's stiffness is much lower compared to PLA and ABS, its total energy absorption capability in gyroid form is not as drastically reduced, indicating the importance of geometry and mass distribution within the gyroid structure. Overall, the results of this study highlight the importance of careful design and optimization of these structures to utilize their unique properties fully.

Engineering of biocompatible Zn-MOFs for efficient delivery of curcumin and amplified anticancer potential against Leukemia cells

Metal-organic frameworks (MOFs) are used as effective drug delivery vehicles owing to their higher structural integrity, low toxicity, biodegradability, and flexible surface functionalities. Zn-MOFs provide a variety of options for drug delivery systems such as zinc ions act as attachment sites, providing cavities among organic ligands, serving as carriers, and they self-assemble via ligand into adaptable structures. However, a lack of knowledge of their biocompatibility at the organic and cellular levels limits their widespread use in biomedical applications. Herein, we engineered the polydopamine (PDA)-coated Zn-MOFs as an efficient delivery system of curcumin (CRM) against leukemia cells. PDA-coated Zn-MOFs were completely characterized through different analytical techniques such as Fourier Transform Infra-red (FTIR) spectroscopy, scanning electron microscopy (SEM), dynamic light scattering (DLS), zeta potential (ZP) analyzer and powder X-ray diffraction (P-XRD). In-vitro CRM loading and release kinetics studies were performed to determine the percent drug loading and releasing efficiency of PDA-coated Zn-MOFs. The anticancer potential of CRM against leukemia cells was significantly increased after encapsulation into PDA-coated MOFs. These findings highlight the great potential of PDA-coated CRM-loaded Zn-MOFs in nano-based drug delivery systems.

Facile orientation control of MOF-303 hollow fiber membranes by a dual-source seeding method

Metal‒organic frameworks (MOFs) are nanoporous crystalline materials with enormous potential for further development into a new class of high-performance membranes. However, the preparation of defect-free and water-stable MOF membranes with high permselectivity and good structural integrity remains a challenge. Herein, we demonstrate a dual-source seeding (DS) approach to produce high-performance, water-stable MOF-303 membranes with hollow fiber (HF) geometry and preferentially tailored crystallographic orientation. By controlling the nucleation site density during secondary growth, MOF-303 membranes with a preferred crystallographic orientation (CPO) on the (011) plane were fabricated. The MOF-303 membrane with CPO on (011) provides straight one-dimensional permeation channels with a superior water flux of 18 kg m−2 h−1 in pervaporative water/ethanol separation, which is higher than that of most of the reported zeolite membranes and 1–2 orders of magnitude greater than that of previously reported MOF membranes. The straight water permeation channels also offer a promising water permeance of 15 L m−2 h−1 bar−1 and a molecular weight cut-off (MWCO ≈ 269) for dye nanofiltration. These results provide a concept for developing ultrapermeable MOF membranes with good selectivity and structural integrity for pervaporation and nanofiltration.

Highly durable superhydrophobic bilayer nanofibrous composite membrane with intermediate interlocked network inspired by mortise and tenon connections for membrane distillation

The membranes for membrane distillation (MD) posed challenges for long-term stable operation due to poor mechanical strength, low flux and susceptibility to wetting. In this study, inspired by conventional mortise and tenon (MT) structure, we constructed a novel robust and porous bilayer composite membrane consisting of superhydrophobic microsphere layer and nanofibrous substrate along with interfacial interlocked networks via a facile integrated casting-recrystallization (ICR) method for highly efficient direct contact membrane distillation (DCMD). During one-step ICR process, amorphous polypropylene (aPP) and isotactic polypropylene (iPP) (a-iPP) with certain mass ratio were completely dissolved in xylene and then cast on the surface of highly porous poly(vinylidene fluoride) (PVDF) nanofibrous substrate at high temperature, in which a crystallization process of the mixed solution occurred in a single step to form PP microsphere layer with a flower-like structure for guarantee of the superhydrophobicity and permeability of the composite membrane. Meanwhile, PP solution infiltrated into the PVDF nanofibrous substrate and then solidified along the fibers and fiber junctions at the initial pouring to create intermediate interlocking connections based on MT construction between the nanofibrous substrate and the microsphere layer, which resulted in the composite membrane with extremely high structural integrity and mechanical properties. The optimal a-iPP/PVDF composite membranes exhibited outstanding mechanical properties (36.6 MPa in tensile strength and 118.0% in strain), significantly superior to PVDF electrospun nanofibrous membrane and commercial PVDF membrane. This unique a-iPP composite membrane with unrelenting superhydrophobicity and high permeability demonstrated a complete barrier to salts with a considerable permeation flux of 54 kg m-2 h-1 in a 70-hour DCMD test (ΔT=40 oC).

Lithium, Ether, and Graphite: A Retrospective Trilogy of the Anode-Electrolyte Interface

Ethers represent a family of solvents widely applied in various battery chemistries, except in the most successful battery—Li-ion batteries (LIBs). It is believed that ether electrolytes are incompatible with graphite anodes in LIBs due to detrimental solvent co-intercalation and exfoliation. Here, we demonstrate that ether electrolytes at standard salt concentration can enable outstanding reversibility and fast-charge capability of graphite anodes in LIBs. In short, for ether electrolytes, the anion and the solid-electrolyte interphase (SEI) govern the electrochemical behaviors of graphite anodes. Firstly, we point out that exfoliation and co-intercalation are not always the root causes of the documented cell failures using graphite anodes. Matching the reductive stability between solvents and salts is key to resolving the interphase problem. Reductively unstable lithium bis(fluorosulfonyl)imide (LiFSI) is the optimal salt paired with 1,3-dioxolane (DOL), enabling weakened Li-solvent interaction, preferential reduction of the FSI anion, and a homogeneous SEI enriched with inorganic species. Consequently, electrolyte reduction and Li-DOL co-intercalation are inhibited. Secondly, reductively stable LiBF4 paired with dimethoxyethane (DME) realizes improved cyclability of graphite based on a cointercalation mechanism. We conducted a holistic investigation into the nature, function, and formation of the heterogeneous SEI. Specifically, we revealed a self-terminating, heterogeneous interphase based on grainy LiF located on the catalytically active edge plane of natural graphite. Thirdly, we discovered a novel cointercalation mechanism, namely, in-situ synthesis of ternary graphite-intercalation compounds in a new electrolyte. We characterize the progressive cointercalation via operando synchrotron X-ray analyses, supporting reduced volume expansion and high structural integrity of the cointercalated graphite. The resulting t-GIC chemistry delivers unprecedented fast charging (1 minute) and ultralong lifetimes exceeding 10,000 cycles. The full cells based on cointercalated graphite display remarkable cycling stability upon a 15-minute charging and excellent rate capability even at -40°C. In these three case studies combined as a trilogy with strong correlation, we clarify a long-standing confusing issue in the LIBs community—that is, the compatibility between ether electrolytes and graphite anodes. This trilogy summarizes and reflects on past experiences with the anode/electrolyte interface (mostly failures of ether electrolytes when cycling graphite anodes) dating back to the 1970s. Learning from history, we exemplify different intercalation chemistries of graphite based on DOL, DME, and another common ether solvent, paired with 1M lithium salts, all showing approximately 99.9% Coulombic efficiency, high capacity retention, and rapid interphase kinetics. Our findings not only shed light on the enigmatic interphase formed by ether electrolytes but also offer critical insights into future electrolyte design for graphite anodes operated under extreme conditions.

Printed High-Entropy Prussian Blue Analogs for Advanced Non-Volatile Memristive Devices.

Non-volatile memristors dynamically switch between high (HRS) and low resistance states (LRS) in response to electrical stimuli, essential for electronic memories, neuromorphic computing, and artificial intelligence. High-entropy Prussian blue analogs (HE-PBAs) are promising insertion-type battery materials due to their diverse composition, high structural integrity, and favorable ionic conductivity. This work proposes a non-volatile, bipolar memristor based on HE-PBA. The device, featuring an active layer of HE-PBA sandwiched between Ag and ITO electrodes, is fabricated by inkjet printing and microplotting. The conduction mechanism of the Ag/HE-PBA/ITO device is systematically investigated. The results indicate that the transition between HRS and LRS is driven by an insulating-metallic transition, triggered by extraction/insertion of highly mobile Na+ ions upon application of an electric field. The memristor operates through a low-energy process akin to Na+ shuttling in Na-ion batteries rather than depending on formation/rupture of Ag filaments. Notably, it showcases promising characteristics, including non-volatility, self-compliance, and forming-free behavior, and further exhibits low operation voltage (VSET = -0.26 V, VRESET = 0.36 V), low power consumption (PSET = 26 µW, PRESET = 8.0 µW), and a high ROFF/RON ratio of 104. This underscores the potential of high-entropy insertion materials for developing printed memristors with distinct operation mechanisms.

Quasi-Single-Crystal Tin Halide Perovskite Films with High Structural Integrity for Near-Infrared Imaging Array Enabling Hidden Object Recognition.

Near-infrared (NIR) image sensors based on solution-processed thin film are gaining prominence in various applications, including security detection, remote sensing, medical imaging, and environmental monitoring, owing to superior penetration capabilities of NIR light. However, the reported perovskite image sensors suffer from limited resolution and performance due to poor structural integrity, bioincompatibility, and constrained response wavelength range from lead-based perovskite materials employed. In this study, we present non-toxic quasi-single-crystal (QSC) CH(NH2)2SnI3 (FASnI3) perovskite films, prepared via a simple spin-coating technique, that demonstrate high structural integrity and effective NIR response. Through a series of in situ characterizations, we reveal that the orderly growth mode of QSC-FASnI3 perovskite films enables a more oriented crystal growth with reduced trap and grain boundaries. Consequently, self-powered NIR photodetector based on QSC-FASnI3 films exhibited large detectivity over 1013 Jones in the NIR range (780-890 nm). Ultimately, due to the high structural integrity, the high-resolution 64×64 (4096) pixels NIR imaging array, exhibiting reduced photo and dark response non-uniformity value, was fabricated on the thin-film transistors (TFT) backplanes, enabling ultraweak NIR light (63 nW cm-2) real-time imaging, fingerprint imaging, and hidden object recognition. This work pioneers the application of lead-free perovskite for high-resolution NIR imaging arrays.

Quasi‐Single‐Crystal Tin Halide Perovskite Films with High Structural Integrity for Near‐Infrared Imaging Array Enabling Hidden Object Recognition

AbstractNear‐infrared (NIR) image sensors based on solution‐processed thin film are gaining prominence in various applications, including security detection, remote sensing, medical imaging, and environmental monitoring, owing to superior penetration capabilities of NIR light. However, the reported perovskite image sensors suffer from limited resolution and performance due to poor structural integrity, bioincompatibility, and constrained response wavelength range from lead‐based perovskite materials employed. In this study, we present non‐toxic quasi‐single‐crystal (QSC) CH(NH2)2SnI3 (FASnI3) perovskite films, prepared via a simple spin‐coating technique, that demonstrate high structural integrity and effective NIR response. Through a series of in situ characterizations, we reveal that the orderly growth mode of QSC‐FASnI3 perovskite films enables a more oriented crystal growth with reduced trap and grain boundaries. Consequently, self‐powered NIR photodetector based on QSC‐FASnI3 films exhibited large detectivity over 1013 Jones in the NIR range (780–890 nm). Ultimately, due to the high structural integrity, the high‐resolution 64×64 (4096) pixels NIR imaging array, exhibiting reduced photo and dark response non‐uniformity value, was fabricated on the thin‐film transistors (TFT) backplanes, enabling ultraweak NIR light (63 nW cm−2) real‐time imaging, fingerprint imaging, and hidden object recognition. This work pioneers the application of lead‐free perovskite for high‐resolution NIR imaging arrays.

Coupled thermo-hydro-mechanical analysis of porous rocks: Candidate of surrounding rocks for deep geological repositories

Deep geological sequestration is widely recognized as a reliable method for nuclear waste management, with expanded applications in thermal energy storage and adiabatic compressed air energy storage systems. This study evaluated the suitability of granite, basalt, and marble as reservoir rocks capable of withstanding extreme high-temperature and high-pressure conditions. Using a custom-designed triaxial testing apparatus for thermal-hydro-mechanical (THM) coupling, we subjected rock samples to temperatures ranging from 20 °C to 800 °C, triaxial stresses up to 25 MPa, and seepage pressures of 0.6 MPa. After THM treatment, the specimens were analyzed using a Real-Time Load-Synchronized Micro-Computed Tomography (MCT) Scanner under a triaxial stress of 25 MPa, allowing for high-resolution insights into pore and fissure responses. Our findings revealed distinct thermal stability profiles and microscopic parameter changes across three phases—slow growth, slow decline, and rapid growth—with critical temperature thresholds observed at 500°C for granite, 600 °C for basalt, and 300 °C for marble. Basalt showed minimal porosity changes, increasing gradually from 3.83% at 20 °C to 12.45% at 800 °C, indicating high structural integrity and resilience under extreme THM conditions. Granite shows significant increases in porosity due to thermally induced microcracking, while marble rapidly deteriorated beyond 300 °C due to carbonate decomposition. Consequently, basalt, with its minimal porosity variability, high thermal stability, and robust mechanical properties, emerges as an optimal candidate for nuclear waste repositories and other high-temperature geological engineering applications, offering enhanced reliability, structural stability, and long-term safety in such settings.

An eco-friendly approach for graphene nanoplatelets by innovative wet thermal expansion and liquid-phase exfoliation

Cost-effective synthesis of high-structural integrity graphene nanoplatelets (GNPs) remains a grand challenge. This study presents an innovative, environmentally friendly and efficient method for synthesizing high-quality GNPs by integrating wet thermal expansion with liquid-phase exfoliation. The thermal expansion of a wet graphite intercalation compound (GIC) in a semi-closed system improves the expansion effectiveness, minimizes the release of fine dust and improves the hydrophilicity of the resulting product. These improvements significantly enhance the effectiveness and efficiency of the subsequent liquid-phase exfoliation by shearing, which produces GNPs in pure water within 30 min with an overall productivity of 38.24 %. GNPs exhibit desirable properties, e.g. few layers (1–2 nm thick), large lateral dimension (a few microns), high sp2 hybridized carbon content (86 %), rich surface functional groups yet a low oxidation level (C/O ratio = 21.7 and electrical conductivity of ∼ 2055 S cm−1). The simplicity, adjustability and scalability of this method, combined with environmental friendliness, make it suitable for various applications and pave the way for further advancements in sustainable nanotechnology practices.

A novel water‐based mechanochemical approach for surface modification of graphene platelets and their epoxy nanocomposites

AbstractGraphene (nano) platelets (GPs) are cost‐effective and possess high structural integrity, but their limited surface functional groups hinder their compatibility with polymers. In this study, an eco‐friendly, water‐based mechanochemical approach was developed to modify GPs with polyacrylamide (PAM), creating PAM graphene platelets (PAM‐GPs) with a grafting ratio of approximately 15%. The platelet was measured to be a few nanometers in thickness, and the grafted PAM provides abundant functional groups, including amide groups, which enhance compatibility with polymers. A typical polymer, bisphenol‐A epoxy, was compounded with PAM‐GPs, resulting in a high degree of exfoliation and dispersion of PAM‐GPs within the matrix. The resulting epoxy/PAM‐GP composites exhibited significantly improved mechanical properties, including an 18% increase in Young's modulus and a substantial enhancement in fracture toughness, with a 71% increase at a low filler fraction of 0.5 wt%. These improvements are attributed to the effective interfacial interaction between the PAM‐GPs and the epoxy matrix, facilitated by the grafted functional groups. This study highlights the potential of PAM‐GPs as toughening fillers for epoxy composites, emphasizing their applicability in enhancing the durability and performance of structural components in industrial applications.Highlights Polyacrylamide (PAM)‐modified graphene platelets by a water‐based approach. A strong interface promoted exfoliation and dispersion of platelets. PAM‐modified platelets improved epoxy modulus and toughness. Fractographic analysis unveils toughening mechanisms.

Optimization of Ni-Cu binder composition and sintering time for enhanced mechanical properties of Mo alloys via liquid phase sintering

Liquid phase sintering of refractory alloys offers a promising approach to enhance mechanical properties while ensuring cost-effectiveness and near-net shaping capabilities. This study systematically explores the impact of sintering time and Ni-Cu binder composition on densification, shape retention, and mechanical properties of Mo alloys processed via liquid phase sintering. The aim is to identify optimal binder composition and sintering time for low-cost production of dense, near-net-shape Mo alloys with superior mechanical properties. The sinterability of Mo compacts is enhanced as the Ni-Cu ratio increases. However, excessive Ni content induces geometric distortion during sintering. Alloys with Ni-rich binders exhibit two liquids at the sintering temperature, each with differing Mo solubility, resulting in a dual-phase matrix on solidification. Both Cu-rich and Ni-rich binder compositions exhibit brittle δ-MoNi intermetallic compound formation, whose quantity increases with prolonged sintering times. Alloys characterized by low Mo solubility in the matrix, high Mo volume fraction, high Mo grain contiguity, and large dihedral angles demonstrate high structural integrity and resistance to geometric distortion. Conversely, alloys featuring high matrix volume fraction, low grain contiguity, elevated Mo solubility in the binder, and strong Mo-matrix interfaces exhibit enhanced strength, hardness, and ductility. Notably, an alloy with a Ni-Cu ratio of 3:1 sintered for just 30 min at 1420°C demonstrates outstanding mechanical properties—hardness of 410 HV, tensile strength of 920 MPa, and elongation of 9 %—comparable to or better than many previously reported refractory alloys.

Electrospun three dimensional TiO2@N/P co-doped carbon nanofibers framework as high-performance anode materials for lithium-ion batteries

Electrospinning combined with heating treatment is employed to fabricate N/P co-doped carbon nanofibers encapsulating homogenous ultrafine TiO2 nanoparticles (TiO2@N/P-CNFs). Characterization results reveal that one-dimensional electrospun composite nanofibers with high electronic conductivity and structural integrity are interconnected with each other to construct a three-dimensional conductive nanofiber network as efficient ion/electron transport channels. Specifically, the Li//TiO2@N/P-CNFs coin cell delivers an initial discharge specific capacity of 754.9 mAh/g at 100 mA/g and maintains the reversible specific capacity of 486.1 mAh/g after 100 cycles. Moreover, the cell expresses the exceptional rate capability with discharge specific capacity of 272.2 mAh/g at 2000 mA/g, whose capacity can be restored to 474.3 mAh/g as soon as the current density is returned to 100 mAh/g. Furthermore, Li//TiO2@N/P-CNFs cell demonstrates a significant pseudocapacitive contribution of 78% at 1.0 mV/s. The excellent electrochemical performance can be explained by the fact that the N/P co-doping strategy is promising strategy for facilitating Li+ ions storage and transfer by broadening interlayer distance and increasing the distribution of defects and active sites. Besides, ultrafine TiO2 nanoparticles with diameter of about 7 nm harness excellent mechanical strength to maintain structural stability upon cycling. Therefore, easily fabricated TiO2@N/P-CNFs composite nanofibers with excellent electrochemical properties may be served as a promising option for advanced anode materials for lithium-ion batteries.

Tweaking the structure and symmetry of Y2B2O7:Eu3+ by B-site engineering for efficient and thermally stable phosphor: Y2Zr2O7 versus Y2Ge2O7

There is an urgent need for synthesizing red emitting phosphor with high photoluminescence quantum yield (PLQY) and good thermal stability for high performing phosphor converted light emitting diodes (pc-LEDs) which are in demand to mitigate carbon emission. Here we have achieved the same through symmetry alteration and structural modification strategy which leads to high PLQY and improved thermal stability. In this work we have synthesized highly symmetric cubic fluorite Y2Zr2O7:Eu3+pyrochlore and replacing the B-site Zr4+by Ge4+ to lower the symmetry and induce structural change to tetragonal Y2Ge2O7:Eu3+ by organic solvent free solid state reactions. Among the three composition Y2Ge2O7: Eu is exhibiting higher emission intensity, higher asymmetry ratio and enhanced PLQY (32.3 %) by virtue of lower symmetry of tetragonal phase. On the other hand, higher thermal stability was achieved for Y2Zr2O7: Eu (97 % at 450 K) endowed by higher structural integrity and stability of pyrochlore phase.

Mixed-Layered Lead Halide Frameworks with High Stability and Efficient Room-Temperature Phosphorescence.

Room-temperature phosphorescent (RTP) materials play a crucial role in optical anticounterfeiting science and information security technologies. Ionically bonded organic metal halides have emerged as promising RTP material systems due to their excellent self-assembly and unique photophysical property, but their intrinsic instability largely hinders their advanced practical applications. Herein, we employ a coordination-driven synthetic strategy utilizing organocarboxylates for the synthesis of two isostructural layered lead halide frameworks. The frameworks adopt a new mixed-layered topology, consisting of alternating [Pb10X9]11+ (X = Cl-/Br-) layers and [Pb6XO3]11+ (X = Cl-/Br-) layers that are coordinatively sandwiched by organocarboxylate layers. The frameworks exhibit long-lived green afterglow emission with the long lifetime of up to 45.89 ms and the photoluminescence quantum yield (PLQY) of up to 43.13%. The Pb2+-carboxylate coordination accelerates the metal-to-ligand charge transfer from the light-harvesting lead halide layers to the phosphorescent organic component, promoting efficient spin-orbit coupling and intersystem crossing. Moreover, the coordination networks exhibit good structural robustness under ambient conditions for at least 12 months, as well as stability in boiling water, acidic and basic aqueous environments. The highly efficient afterglow and high structural integrity enable multiple anticounterfeiting applications across diverse chemical environments.