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We explore the existence of spin glass phase in FeCo/FePt bilayers arising due to disordered ferromagnet. The non-ergodic and highly degenerate landscape of the spin glass phase at low temperature explains the origin of complex magnetic texture in the FeCo/FePt system. Upon cooling the bilayered system, the magnetic texture undergoes spin freezing below 120 K as evident from the bifurcations in zero field cooling and field cooling magnetizations at low magnetic field as a manifestation of broken ergodicity. The uncompensated magnetic moments originating in the spin glass state result in slow time dynamics of thermoremanent magnetization. Consequently, the bilayers demonstrate an intriguing magnetic memory effect in which the magnetic state of the system could be retrieved upon isothermal ageing below 120 K after reversing the temperature cycle. Thermal treatment deteriorates the spin glass behaviour and shows a transition to strong ferromagnetic character in FeCo/FePt bilayers. [ABSTRACT FROM AUTHOR]

This study explores the effects of atomic-level factors on the performance of CeO 2 when interacting with SiO 2 films. It specifically examines how different precursors, the ratio of Ce to OH, and reaction temperatures influence outcomes. Our findings reveal that smaller particles, around 5 nm in size, created using a Ce4+ precursor, are more effective at removing SiO 2 films compared to larger, more crystalline particles from a Ce3+ precursor. This is due to their increased interaction with the SiO 2 film during the polishing process, challenging the conventional emphasis on mechanical abrasion in chemical mechanical planarization (CMP) and highlighting the crucial role of chemical interactions. Further analysis through FT-IR and TGA-FTIR techniques showed distinct functional group profiles on the ceria surfaces. Ceria derived from Ce4+ exhibited a higher presence of OH and NO 3 groups, enhancing adsorption capabilities, as verified by CHN analysis. Importantly, first-principles calculations identified these surface groups as key to improving adhesion to SiO 2 films. Surfaces of amorphous CeO 2 , rich in -OH and -NO 3 groups, showed significantly higher adhesion levels than their crystalline counterparts, connecting crystallinity to chemical functionality. This new insight leads to the possibility of designing next-generation CeO 2 abrasives with increased chemical activity. [ABSTRACT FROM AUTHOR]

The B-site complex BaZr 0.1 Ti 0.9 O 3 (BZT) microplatelets with perovskite-structured were synthesized, using the Bi 4 (Zr 0.1 Ti 0.9) 3 O 12 (BIZ 0.1 T 0.9) as a precursor. The precursor had a high aspect ratio, with an average size of ∼8.0 μm. Later, B-site complex BZT microplatelets were obtained via molten salt methods. The influence of n(BIZ 0.1 T 0.9):n(BaCO 3) ratio and calcined temperature in the composition, morphology and local piezoelectric and ferroelectric behaviour for BZT microplatelets was deeply discussed. The result showed that the reactants ratio determined the supersaturation degree in the molten salt environment, while the calcined temperature determined the crystallinity of BZT microcrystals. Overall, with the n(BIZ 0.1 T 0.9):n(BaCO 3) ratio was 1:4, the BZT microcrystal calcined at 900 °C had a better plate-like morphology. Manwhile, the micropizoelectric properties of BZT microplatelet was studied, achieving a maximum d 33 * of ∼330 pm/V. The result indicated that the B-site complex BZT microplatelets is a potential templates for textured ceramics. [ABSTRACT FROM AUTHOR]

In-situ consolidation of thermoplastic composites using Automated Fibre Placement (AFP) technology is an emerging manufacturing technique, offering tailored composite properties through customised processing parameters. Multiple competing parameters during AFP manufacturing influence the quality and mechanical performance of the laminates. These lay-up parameters are interrelated, and often require comprehensive experimental characterisation which is costly and time-intensive. This study aims to optimise the fracture toughness of in-situ consolidated thermoplastic composite (AS4/APC-2) and investigate the mechanisms that contribute to it. Taguchi's method is employed to efficiently analyse the effect of various process parameters at multiple levels. Based on the obtained results, a considerable effect of process parameters on Mode I and II fracture toughness is observed. The statistical analysis reveals that the Hot Gas Torch (HGT) temperature required for AFP processing significantly affects the Mode I fracture toughness, contributing to 33.8%. Whereas, the consolidation force, another key processing parameter in AFP notably affects Mode II fracture toughness, with the contribution of 81.8%. The analysis of variance (ANOVA) reveals interdependent processing parameter relations for both fracture modes. A validation test showed good agreement between the predicted fracture toughness and the experimental test. [ABSTRACT FROM AUTHOR]

The effect of surface roughness and temperature on wettability of polyethylene terephthalate (PET) melt on steel substrates is assessed. A plot of contact angle, Φ, Vs. time, τ, revealed the significant effect of temperature on wetting compared to surface roughness. The surface free energy of the steel substrate decreased by about 22% with increase in surface roughness from 0.21 to 3.8 μm. The measured surface tension of the polymer melt was 31.36 mN m−1 at 260°C. The variation in the cooling rate of the solidifying molten PET resulted in varying degree of polymer opacity. The opacity variations were quantified as a function of pixel intensity. The opacity of the solidified PET melt drops sharply declines at lower cooling rates before stabilizing at higher rates. No significant difference in the mean pixel intensity is observed between PET melts solidified at different substrate temperatures. Three distinct regimes in PET melt solidification are identified: (i) increased crystallization propensity at lower cooling rates (<8°C min−1), (ii) dominance of amorphous characteristics at higher rates (>199°C min−1), and (iii) a transitional regime at intermediate cooling rates. [ABSTRACT FROM AUTHOR]

Developing highly efficient catalysts for the hydrogen evolution reaction (HER) is crucial for advancing renewable hydrogen energy technologies. Heterophase nanomaterials have shown great promise in catalysis, owing to the synergistic effect among various phases and the abundance of active sites located at the phase boundaries or interfaces. However, achieving precise control over these phase structures during synthesis remains a significant challenge. In this work, we explored a one-pot synthesis method for amorphous/crystalline heterophase Rh nanoparticles, with crystallinity tunable by adjusting the quantity of urea and reaction duration. Due to the increased electrochemical active sites, enhanced electron transport, the resulting amorphous/crystalline heterophase Rh exhibits superior HER activities in both acidic (with an overpotential of 27 mV) and alkaline media (with an overpotential of 21 mV), surpassing that of commercial Pt/C and crystalline Rh. Theoretical calculations indicate that the amorphous/crystalline structure reduces the kinetic barrier for water splitting and optimizes adsorption free energy of hydrogen (ΔG H∗), thereby enabling the catalyst to exhibit significantly enhanced HER performance. This exploration offers a valuable reference for designing amorphous/crystalline heterophase structures and demonstrates the great potential of phase engineering strategy in the development of electrocatalysts. [Display omitted] • Amorphous/crystalline heterophase Rh can be prepared with urea in a simple method. • The crystallinity can be tuned by modifying the amount of urea and reaction time. • Amorphous/crystalline Rh exhibited a higher HER performance than crystalline Rh. • Amorphous/crystalline structure optimizes adsorption energy of reactant. [ABSTRACT FROM AUTHOR]

This study investigated the effects of alkaline treatment on the pineapple leaf fiber (PALF) cellulose extraction and the properties of cellulose hydrogel. PALF was treated with different concentrations of sodium hydroxide (NaOH) (2 to 10 wt %) and at room temperature (RT) and 80 °C. Then, extracted cellulose was then dissolved in N,N'‐dimethyl acetamide (DMAc)/lithium chloride (LiCl) solvent system and formed into hydrogel by phase inversion method. The Fourier transform infrared spectra shows the peak disappearance at 1606 cm−1 proves that lignin was removed starting from 6 and 4 wt % NaOH at RT and 80 °C, respectively. Higher NaOH concentrations treatment increased thermal stability and the crystallinity (71 to 79 %) of the fibers. Higher NaOH concentration and treatment temperature enhanced cellulose extraction from PALF, leading to more physical crosslinking during hydrogel formation. High amount of cellulose extracted decreased the hydrogel's swelling equilibrium and increased the gel fraction. The highest transmittance (87.8 %) and the lowest intensity of absorbance (at 280 nm corresponding to lignin) were obtained by the hydrogel prepared with PALF treated with 8 wt % NaOH at 80 °C. Clearly, this research findings provide new insights into optimizing cellulose extraction using alkaline treatment specifically for cellulose hydrogel formation. [ABSTRACT FROM AUTHOR]

In this paper, Bi2212 superconducting thin films were prepared with metal acetate as salt source and a mixture of acetic acid and N,N-dimethylformamide (DMF) as solvent. The volatilization process of the solvent was regulated by changing the ratio of the mixed solvent, which in turn achieved the regulation of the surface morphology and crystallinity of the Bi2212 superconducting films. The mechanism of the mixed solvents on the crystallinity and surface quality of Bi2212 superconducting films was systematically investigated. The results showed that the Bi2212 superconducting films were all (00 l) epitaxial growth. The grain size of Bi2212 increased continuously with the increase of the proportion of acetic acid in the solvents. The grain size of the largest grain size was 43.8 nm when the proportion of acetic acid was 80 %. However, the high proportion of acetic acid in the mixed solvents reduced the surface quality of Bi2212 thin films. The minimum surface roughness was 15.0 nm at 40 % acetic acid. All the samples exhibited good superconducting properties. This work provides a research basis for the systematic preparation of multicomponent oxide thin films. [ABSTRACT FROM AUTHOR]

The ternary strategy proves effective for breakthroughs in organic photovoltaics (OPVs). Elevating three photovoltaic parameters synergistically, especially the proportion‐insensitive third component, is crucial for efficient ternary devices. This work introduces a molecular design strategy by comprehensively analyzing asymmetric end groups, side‐chain engineering, and halogenation to explore the outstanding optoelectronic properties of the proportion‐insensitive third component in efficient ternary systems. Three asymmetric non‐fullerene acceptors (BTP‐SA1, BTP‐SA2, and BTP‐SA3) are synthesized based on the Y6 framework and incorporated as the third component into the D18:Y6 binary system. BTP‐SA3, featuring asymmetric terminal (difluoro‐indone and dichloride‐cyanoindone terminal), with branched alkyl side chains, exhibited high open‐circuit voltage (VOC), balanced crystallinity and compatibility, achieving synergistic enhancements in VOC (0.862 V), short circuit‐current density (JSC, 27.52 mA cm−2), fill fact (FF, 81.01%), and power convert efficiency (PCE, 19.19%). Device based on D18/Y6:BTP‐SA3 (layer‐by‐layer processed) reached a high efficiency of 19.36%, demonstrating a high tolerance for BTP‐SA3 (10–50%). This work provides novel insights into optimizing OPVs performances in multi‐component systems and designing components with enhanced tolerance. [ABSTRACT FROM AUTHOR]

Rapid, nondestructive characterization techniques for evaluating the degree of crystallinity and phase segregation of organic semiconductor blend thin films are highly desired for in‐line, automated optoelectronic device fabrication facilities. Here, it is demonstrated that reflection polarized optical microscopy (POM), a simple technique capable of imaging local anisotropy of materials, is capable of determining the relative degree of crystallinity and phase segregation of thin films of polymer:fullerene blends. While previous works on POM of organic semiconductors have largely employed the transmission geometry, it is demonstrated that reflection POM provides 3× greater contrast. The optimal configuration is described to maximize contrast from POM images of polymer:fullerene films, which requires Köhler illumination and slightly uncrossed polarizers, with an uncrossing angle of ±3°. It is quantitatively demonstrated that contrast in POM images directly correlates with 1) the degree of polymer crystallinity and 2) the degree of phase segregation between polymer and fullerene domains. The origin of the bright and dark domains in POM is identified as arising from symmetry‐broken liquid crystalline phases (i.e., dark conglomerates), and it is proven that they have no correlation with surface topography. The use of reflection POM as a rapid diagnostic tool for automated device fabrication facilities is discussed. [ABSTRACT FROM AUTHOR]

As a class of predominantly used cathode interlayers (CILs) in organic solar cells (OSCs), perylene‐diimide (PDI)‐based polymers exhibit intriguing characteristics of excellent charge transporting capacity and suitable energy levels. Despite that, PDI‐based CILs with satisfied film‐forming ability and adequate solvent resistance are rather rare, which not only limits the further advance of OSC performances but also hinders the practical use of PDI CILs. Herein, we designed and synthesized two non‐conjugated PDI polymers for achieving high power conversion efficiency (PCE) in diverse types of OSCs. The utilization of oligo (ethylene glycol) (OEG) linkage enhanced the n‐doping effect of PDI polymers, leading to an improved ability of the CIL to reduce work function and improve electron transporting capability. Moreover, the introduction of the non‐ionic OEG chain effectively improve the wetting property and solvent resistance of PDI polymers, so the PPDINN CIL can withstand diverse processing conditions in fabricating different OSCs, including conventional, inverted and blade‐coated devices. The binary OSC with conventional structure using PPDINN CIL showed a PCE of 18.6 %, along with an improved device stability. Besides, PPDINN is compatible with the large‐area blade‐coating technique, and a PCE of 16.6 % was achieved in the 1‐cm2 OSC where a blade‐coated PPDINN was used. [ABSTRACT FROM AUTHOR]

In this research, we present a novel facile, scalable, and template-free technique of synthesizing graphitic carbon nitride (g-C 3 N 4) nanotubes for generating hydrogen through photocatalysis. The hybrid technique involves a two-fold mixing of the precursor materials melamine (M) and cyanuric acid (CA), involving ball milling followed by solution mixing. By varying the M:CA molar ratios, different compositions of g-C 3 N 4 nanotubes were fabricated. The study focused on examining the surface characteristics and the photocatalytic hydrogen evolution performance of these nanotubes. Nanotubes with high specific surface area of 206 m2 g−1 for M:CA molar ratio of 1:3 and 178 m2 g−1 for M:CA molar ratio of 1:5 were produced, with H 2 evolution rates of 543 μmol h−1 g−1 and 740 μmol h−1 g−1 respectively, which were an increase of 4 and 5-fold, respectively, in comparison to the pristine sample. The enhanced efficiency of hydrogen production through photocatalysis by nanotubes, when contrasted with pristine material, can be ascribed to their high crystallinity, superior specific surface areas, decreased recombination rates of electron-hole pairs generated during light exposure, and improved dynamics of charge carriers. This hybrid technique provides a new pathway for cost-effective fabrication of g-C 3 N 4 nanotubes with substantial surface areas and high yield photocatalysts on an industrial scale, without the use of templates and hydrothermal processes for efficient hydrogen generation. [Display omitted] • Graphitic carbon nitride (g-C 3 N 4) nanotubes were synthesized using a novel hybrid synthesis technique involving dual precursor mixing. • High specific surface area g-C 3 N 4 nanotubes of ∼206 m2 g−1 and 178 m2 g−1 were achieved. • A g-C 3 N 4 nanotube with a 1:3 melamine-cyanuric acid molar ratio achieved enhanced H 2 evolution performance (740 µmol h⁻¹ g⁻¹). • The stability of g-C 3 N 4 nanotubes was shown by the consistent H 2 evolution rate during extended irradiation. [ABSTRACT FROM AUTHOR]

This study focuses on the development of environmentally sustainable polypropylene (PP)-based composites with the potential for biodegradability by incorporating cellulose and the oligomeric siloxane ES-40. Targeting industrial applications such as fused deposition modeling (FDM) 3D printing, ES-40 was employed as a precursor for the in situ formation of silica particles via hydrolytic polycondensation (HPC). Two HPC approaches were investigated: a preliminary reaction in a mixture of cellulose, ethanol, and water, and a direct reaction within the molten PP matrix. The composites were thoroughly characterized using rotational rheometry, optical microscopy, differential scanning calorimetry, and dynamic mechanical analysis. Both methods resulted in composites with markedly reduced crystallinity and shrinkage compared to neat PP, with the lowest shrinkage observed in blends prepared directly in the extruder. The inclusion of cellulose not only enhances the environmental profile of these composites but also paves the way for the development of PP materials with improved biodegradability, highlighting the potential of this technique for fabricating more amorphous composites from crystalline or semi-crystalline polymers for enhancing the quality and dimensional stability of FDM-printed materials. [ABSTRACT FROM AUTHOR]

Despite major advances in efficiency, the operational stability of organic photovoltaic (OPV) devices remains poor. Therefore, understanding the degradation mechanisms and identifying potential solutions to improve device stability is critical to enabling the widespread commercialization of OPVs. Herein, simple filtration of the PBDB‐T:ITIC photoactive layer (PAL) solution prior to film deposition is demonstrated to enhance OPV device operational stability without compromising initial device performance. The effect of filtration, a commonly used but poorly understood OPV fabrication step, is investigated using a range of chemical, structural, and optoelectronic methods, on solutions and films. Filtration is found to remove large aggregates from solution without disrupting nanoscale preaggregation, resulting in enhanced acceptor ordering in PBDB‐T:ITIC thin films, significantly improving morphological stability and photostability. This simple and facile method is confirmed to be a general strategy that also works for other PBDB‐T‐containing OPV blends, including Y6‐based systems, and highlights how subtle changes in morphology can result in dramatic differences in operational stability. [ABSTRACT FROM AUTHOR]

A three-dimensional-micro-pulling-down (3D-μ-PD) method was developed for the growth of 3D shaped single crystals, and spring-shaped sapphire single crystals were grown by the 3D-μ-PD method using Mo crucibles with different dies. The shape of the die significantly affected the growth stability and shape control of the spring-shaped single crystals. Spring-shaped sapphire single crystals with a smaller helical pitch and larger helical radius were obtained easily using a Mo crucible with a sharp conical die compared to that with a blunt conical die. However, spring-shaped sapphire single crystals grown using a Mo crucible with an inverse conical die can be obtained with smaller helical pitches, and the shape of the cross-sectional plane is a horizontally extended elliptical shape. The difference in the shape of the cross-sectional plane for spring-shaped sapphire single crystals affects the crystallinity and mechanical properties. Furthermore, crystals grown using the Mo crucible with the inverse conical die exhibited a larger shrinkage rate in the compression test. [ABSTRACT FROM AUTHOR]

The present research article demonstrates the dispersion of boehmite (BHM) nanoparticles into sericin (SER) from silk industry waste with polyvinyl alcohol (PVA) to enhance the optical, mechanical, thermal and electrical characteristics of PVA/SER blend nanocomposites prepared by a simple green synthesis. Techniques such as Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), UV visible spectroscopy, field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were carried out for the characterization of the prepared composites. XRD revealed the increased crystallinity of the polymer blend by the reinforcement of BHM. The existence of intermolecular interactions in the blend composite was confirmed by FTIR and UV spectroscopy. The optical bandgap energy of the biopolymer blend decreases with the inclusion of BHM. The SEM and HR-TEM confirmed the homogeneous dispersion of BHM in the blend at 5 wt% loading. The glass transition temperature and thermal stability of the blend nanocomposites were significantly improved by the inclusion of BHM was deduced from DSC and TGA. The dielectric constant and AC conductivity were remarkably increased with the reinforcement of nanoparticles. The activation energy obtained from AC conductivity decreased with temperature. The mechanical properties of the blend nanocomposites (hardness, tensile strength and Young's modulus) were greatly increased in presence of BHM. The 5 wt% sample has the highest tensile strength, Young's modulus, dielectric constant, AC conductivity and optical properties, allowing it to be used to make optoelectronic devices with better charge-storing capacity and flexible-type electrochemical gadgets. [ABSTRACT FROM AUTHOR]

We focus on in-plane and out-of-plane crystallinities of the MgB 2 superconductor. These two structural properties were evaluated in terms of peak broadening at lower angles in the X-ray diffraction. The angular behavior of the in-plane and out-of-plane peaks was used to compare it with the corresponding behavior estimated in the case of several crystallite sizes (that affect the in-field superconductivity of MgB 2). We propose that this comparison allows a simple evaluation to provide insight into the individual influences of in-plane and out-of-plane crystallinities on the in-field critical current density (without needing to calculate numerical values of crystallite sizes and lattice strains of fabricated MgB 2 materials). For this study, we used MgB 2 samples sintered at different temperatures. The sintering conditions affected not only the crystallinities but also the phase compositions. The behavior of the compositions, including amorphous phases, was also evaluated by using a quantitative analysis for X-ray diffraction results. [Display omitted] [ABSTRACT FROM AUTHOR]

Cellulose acetate (CA), synthesized by solid–liquid acetylation of low crystalline cellulose (LCCell) obtained by cold shearing in a short time under environmentally benign conditions, effectively enhanced the crystallization of poly(lactic acid) (PLA). The composite of PLA compounded with CA from LCCell exhibited higher crystallinity of PLA and flexural modulus than those from pristine PLA. CAs obtained from crystalline and recrystallized cellulose also improved the mechanical strength of PLA by compounding, but their effects were weaker than that of CA from LCCell. The factor of the effectiveness of CA obtained from LCCell is the higher miscibility with PLA originating from the sufficiently released interchain hydrogen bonds in the cellulose fibrils by cold shearing, which allows the dissolution of macroscopic aggregation of the CA chains in the composite. [ABSTRACT FROM AUTHOR]

This study investigates the morphology and properties of biocomposites based on a blend of poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) and poly (lactic acid) (PLA) 50/50 (w/w) reinforced with untreated (UNDF) and alkali‐treated (ATDF) Diss (Ampelodesmos mauritanicus) fibers at 20 wt. %. Moreover, PHBV‐g‐MA used as the compatibilizer was added at 5 wt. % to the alkali‐treated biocomposites. Morphology, and crystallinity, thermal, thermo‐mechanical, rheological and mechanical properties of PHBV/PLA biocomposites were studied. The study showed that the treated Diss fibers were uniformly dispersed in both PLA and PHBV phases. This results in a good interfacial adhesion between the components, as observed by scanning electron microscopy (SEM). Further, the results also indicated that the compatibilized biocomposite samples showed an enhancement in crystallinity degree and heat deflection temperature (HDT) passing from 48.7% to 62.4% and 119.2 to 132.9°C, respectively, in comparison with the neat blend. Similar trend is also observed with the tensile data indicating a significant increase in Young's modulus by almost 48.5% compared to PHBV/PLA matrix. This is due to better interactions between Diss fibers and PHBV/PLA matrix. The results suggest the occurrence of a synergistic effect between PHBV‐g‐MA and alkali‐treated Diss fibers in the development of materials with interesting properties and could be a potential means to expand their applications. [ABSTRACT FROM AUTHOR]

Cellulose at different scales from lignocellulosic biomass is an important biopolymer for advanced industrial applications. Nevertheless, pretreatments and delignification processes affect most of the physicochemical properties of the final cellulosic products, such as purity, thermal stability, and mechanical behavior. Hence, it is crucial to find suitable extraction procedures. This study intends to point out the importance of the choice of extraction techniques, and it focuses on the isolation of α-cellulose from Aleppo pine, for which two-delignification processes, namely, kraft or organosolv, were employed, followed by either acidified sodium chlorite or alkaline peroxide treatments. Microcrystalline cellulose (MCC) was subsequently prepared through acid hydrolysis. A comparative study was undertaken to assess the efficiency of each treatment by analyzing the chemical composition, molecular weight distribution, structure, crystallinity, morphology, and thermal stability of the different products. The obtained pure MCC exhibited interesting features such as rod-like shape, high crystallinity (74–85%), and high thermal stability (>342 °C) than the commercial MCC or those derived from other natural sources, for which minor differences are observed for the different MCCs obtained from a procedure to another. Interestingly, the chlorine-free delignification process, i.e., organosolv followed by alkaline hydrogen peroxide treatment, allowed obtaining MCC with outstanding characteristics. The findings of this study demonstrated that the delignification process potentially affected the quality of the extraction of MCC from Aleppo pine, which may find promising applications, especially as polymer reinforcements, dietary food, and pharmaceutics. [ABSTRACT FROM AUTHOR]

In order to improve the solubility of metallated monomers and product crystallinity, metal–covalent organic frameworks (MCOFs) are commonly prepared via high‐temperature sol‐vothermal synthesis. However, it hampers the direct extraction of crystallization evolution information. Exploring facile room‐temperature strategies for both synthesizing MCOFs and exploiting the crystallinity mechanism is extremely desired. Herein, by a novel single‐phase synthetic strategy, three MCOFs with different microstructure is rapidly prepared based on the Schiff base reaction between planarity‐tunable C3v monomers and metallated monomers at room temperature. Based on detailed time‐dependent experiments and theoretical calculations, it is found that there is a planarity‐tuned and competitive growth relationship between disordered structures and crystal nucleus for the first time. The high planarity of monomers boosts the formation of crystal nucleus and rapid growth, suppressing the forming of amorphous structures. In addition, the microenvironment effect on selective photocatalytic coupling of benzylamine (BA) is investigated. The strong donor‐acceptor (D‐A) MCOF exhibits efficient photocatalytic activity with a high conversion rate of 99% and high selectivity of 99% in 5 h under the 520 nm light irradiation. This work opens a new pathway to scalable and efficient synthesis of highly crystalline MCOFs. [ABSTRACT FROM AUTHOR]

Lightweight and high‐strength polymer–metal hybrid structures are favored for reducing material and energy consumption. In this study, carbon fiber‐reinforced polyamide 6 (CFPA) composite materials were prepared through melt blending, and 30 wt% CFPA exhibited the highest shear strength and lowest shrinkage rate among other carbon fiber contents. With pretreatments of anodizing and etching treatment, injection molded direct joining was employed to create polyamide 6 (PA)/CFPA–Aluminum alloy (Al) composites. The impacts of the injection temperature and speed on the bonding strength of the PA/CFPA–Al composite materials were investigated. The characterization results confirmed that carbon fiber doping reduces the coefficient of linear thermal expansion (CLTE) and enhances crystallization ability of PA. The higher injection temperatures and lower injection speed significantly increase the crystallinity of PA and the infiltration of the molten polymer into the nanoporous anodic aluminum oxide films. When the injection temperature was 270°C and the speed was 6 mm/s, the bonding strength of the PA–Al hybrid structure reached a maximum of 36.6 MPa. When the injection temperature was 300°C, the bonding strength of the CFPA–Al hybrid structure reached a maximum of 40.8 MPa. Adhesive parts with high shear bonding strength are critical to satisfying engineering requirements and have significant potential, particularly in polymer–metal composite structures. The polymer‐metal hybrid structure can meet the high interfacial bonding strength required in most engineering applications. Highlights: Injection temperature and speed in IMDJ affect PA crystallinity.Carbon fiber doping reduces the CLTE of PA and increases the shear strength.High temperatures and low injection speeds are beneficial to adhesives.The bonding strength of PA–Al reached a maximum of 36.6 MPa.The bonding strength of CFPA–Al reached a maximum of 40.8 MPa. [ABSTRACT FROM AUTHOR]

As the efficiency of single‐junction organic solar cells (OSCs) is about to break 20%, more research effort is needed to achieve long‐term device stability for commercialization. The complex active layer microstructure of bulk‐heterojunctions challenges the degradation mechanism study, especially for the morphological changes under thermal stress. In this work, this issue can be overcome by employing planar‐heterojunction (PHJ) OSCs with well‐defined bi‐layered structures, which enables effective control of the microstructure of polymer donor layers. The evolution of photovoltaic parameters of the PHJ OSCs under thermal stress is specifically revealed, which is strongly related to the inter diffusion of small molecular acceptors into the amorphous phases of the polymer donors. Increasing the crystallinity of polymer donors can effectively stabilize the donor/acceptor interfaces and the photovoltaic performances. The work puts forward effective strategies to improve the morphological stability of OSCs and alternative approaches for mechanistic studies on the thermal stability of OSCs. [ABSTRACT FROM AUTHOR]

Highlights This study aims at the assessment of damage on crystallinity of fiber reinforced thermoplastic (FRTP) composites resulting from mechanical polishing to demonstrate a novel methodology enabling comprehensive crystalline structural characterization. Investigating the crystalline structure is relevant for understanding the relationship with the mechanical properties. In a previous study, FRTPs have successfully been processed to the thickness of 5 μm or below via an innovative polishing strategy, which for the first time visualized the crystalline morphologies by polarized optical microscopy. Analyzing these sections via micro‐Raman and micro‐infrared spectroscopies facilitate the quantification of these structure. However, no study reports on the correct interpretation of FRTP data appropriately considering the damage resulting from mechanical polishing to date. Herein, we report fundamental knowledge on this aspect via detailed Raman micro‐spectroscopic investigations to demonstrate our novel strategy. Four types of FRTPs with major matrix resins (GF/PBT, CF/PA6, CF/PEEK and GF/PP) were analyzed and the damage on both polished cross‐sections, prepared by traditional process, and the thin sections was confirmed to be approx. 1%–2% crystallinity, which solidified the credibility of the obtained analytical data. Then, the newly established methodology of ‘cross‐referenceable microscopic and micro‐spectroscopic analyses for FRTPs’ was applied for comprehensive crystalline structural characterization. Cross‐sectioning and thin‐sectioning of FRTPs. Evidencing of damage on the crystallinity resulting from mechanical polishing. Equations to convert Raman spectral data into crystallinity. Strategy for considering the anisotropy of Raman measurements. Practical application of novel microscopic and micro‐spectroscopic strategies. [ABSTRACT FROM AUTHOR]

In the present paper, we studied the microstructural and sensing behaviors of undoped SnO2 and PbO-doped SnO2 thick film. Three samples have been fabricated using the screen-printing technique on an aluminum substrate and these are S1 (undoped SnO2) S2 (1wt% PbO doped SnO2 firing at 800 oC), and S3 (1 wt% PbO doped SnO2 firing at 900 oC). XRD and AFM techniques are used to observe the microstructural behaviors and it is found that the crystallite size decreases with PbO doping. The reduction in crystallinity is to improve the sensing application. The sensing properties such as sensing response, selectivity, and transient time of the deposited thick films were studied at an operating temperature of 200 oC for various test gases such as ethanol, LPG, and acetone concentrations (0–5000 ppm level). Also, we found that the response of sensor S3 to the ethanol gas is ~ 3.38 times of LPG and ~ 1.95 times that of acetone gas. The response and recovery times of the ethanol gas for the S3 sensor are 41s and 125s, respectively. Therefore, the PbO doping improves the response and recovery time for ethanol gas (5000 ppm) over LPG and acetone. [ABSTRACT FROM AUTHOR]

Many non-destructive optical testing methods are currently used for material research, providing various information about material parameters. At RECENDT, a multimodal experimental setup has been designed that combines terahertz (THz) spectroscopy, optical coherence tomography (OCT), infrared (IR), and Raman spectroscopy with a tensile test stage. This setup aims to gather material information such as crystallinity and optical parameters of high-density polyethylene (HDPE) during a tensile test. The setup compares common IR and Raman spectroscopy and the less common optical methods THz and OCT. Complementarity is achieved through different frequency ranges and measurement approaches, resulting in different measured optical material parameters and depths. During tensile testing, HDPE samples with varying crystallinity were analysed, and the determined optical parameters such as refractive index, birefringence, scattering coefficient of decay, and penetration depth can be correlated with the change in crystallinity. These findings demonstrate that the optical methods and their outcomes can be interconnected. With further optimization of the experimental setup, it would be possible to observe the alignment of fibres in fibre composite panels and the stress distribution of polymers effectively. This opens interesting possibilities for polymer characterization in the future, including quality control during moulding processes and material testing. [ABSTRACT FROM AUTHOR]

Fiber-reinforced thermoplastic composites (FRTPs) are gaining increasing attention and widespread use in engineering applications due to their high specific strength and stiffness, excellent toughness, and recyclability. The mechanical properties of these composites are closely tied to their crystallization process, making it crucial to accurately describe this phenomenon. Existing theoretical models for analyzing the non-isothermal crystallization of thermoplastic composites often face challenges relating to the complexity of obtaining multiple parameters and the difficulty of achieving a final relative crystallinity of 1. To address these issues, this paper introduces a novel functional form of the crystallization rate parameter K(T), tailored for engineering applications, and proposes an improved Mampel model. This model assumes K(T) to be zero before the onset of crystallization and also to be linearly dependent on temperature thereafter, ensuring that the final relative crystallinity reaches 1. The model requires only two easily accessible parameters: the initial crystallization temperature (Ts) and the linear slope (k). The simplicity of the model makes it particularly well suited to engineering applications. This provides a straightforward and effective tool for describing the non-isothermal crystallization kinetics of fiber-reinforced thermoplastic composites. [ABSTRACT FROM AUTHOR]

The advantages of 3D materials as guest components of ternary organic solar cells (TOSCs) are being realized, showing great potential in improving device performance. However, the correlation between their distinctive 3D structure and device performance remains largely unexplored. Herein, a 3D acceptor named SF‐HR is cost‐effectively synthesized utilizing a twisted spirofluorene core. SF‐HR shows an edge‐on oriented packing but not the disordered aggregation as other 3D molecules. When introduced into D18:Y6 binary system, SF‐HR can induce more predominant face‐on packing and finer domain size in ternary blend, which facilitates exciton dissociation and multi‐direction charge transport. Besides, SF‐HR exhibits complementary absorption and cascaded energy levels with D18 and Y6, contributing to the improvement of short‐circuit current density (Jsc) and open‐circuit voltage (Voc), respectively. Accordingly, the optimized ternary device achieves higher Voc of 0.893 V, Jsc of 27.13 mA cm−2, and fill factor (FF) of 77.8%, respectively, than that of the host binary device, yielding an excellent efficiency of 18.85%. This success demonstrates that the utilization of a crystalline 3D material as a guest component represents a promising strategy for achieving state‐of‐the‐art OSCs, which is conducive to understanding the relationship between 3D guest structure and device performance from a new perspective. [ABSTRACT FROM AUTHOR]

Herein, a low RESET current 1T1R mushroom‐cell phase‐change memory (PCM) device that uses fiber‐textured homostructure GeSbTe (GST) grown on highly oriented TiTe2 seed layer is reported. The homostructure device outperformed the industry standard device, that uses doped polycrystalline GST, on most figures of merit. The homostructure devices are also benchmarked against superlattice (SL) PCM devices with 10 periods of 5/5 nm GST/Sb2Te3 grown on the TiTe2 seed layer, and are found to have same low RESET current. It is also observed by transmission electron microscopy that the alternating layers of GST/Sb2Te3 and TiTe2/Sb2Te3 in SL devices are intermixed in the switched region after the devices are cycled with RESET/SET pulses. Additionally, when the SL device is left in the SET state, the intermixed switched region crystallinity is textured and exhibits van der Waals gaps. The SL PCM devices require a precise layered structure that is hard to yield on a full wafer scale. In contrast, fiber‐textured homostructure PCM cells reported here are easily manufacturable, while providing similarly low RESET current and low‐resistance drift, which makes this device suitable for analog artificial intelligence computation. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of acid or alkali modification of isolated cassava starch (ICS) on its physicochemical properties. Acetic acid concentrations of 5%, 10%, and 20% v/v (0.87, 1.73, and 3.46 M, respectively) and calcium hydroxide concentrations of 0.15%, 0.20%, and 0.30% w/w (0.02, 0.025, and 0.04 M, respectively) were tested independently and compared with untreated isolated starch. The scanning electron microscope (SEM) shows starches with polyhedral and semispherical shapes; these modifications do not change the surface of the starch granules. Nanocrystals with orthorhombic crystal structure were extracted from ICS. Transmission electron microscopy (TEM) shows crystallites with a size (two‐dimensional) of 20 ± 5 nm in length and 10 ± 2 nm in width and reveals that this starch contains nanocrystals with orthorhombic crystal structure. The X‐ray patterns show that these nanocrystals are unaffected by acidic or alkaline treatments. The Ca+2 and CH3COO− ions do not interact with these nanocrystals. The alkaline treatment only affects the gelatinization temperature at a Ca(OH)2 concentration of 0.30%. Low concentrations of acidic and alkaline treatments affect the ability of cassava starch to absorb water and reduce the peak and final viscosity. The infrared spectra show that the modifications lead to C–H and C═C bond formations. ICS‐B 0.30 can modify the amorphous regions of the starch, and the acid treatment leads to acetylation, which was confirmed by the presence of an IR band at 1740 cm−1. [ABSTRACT FROM AUTHOR]

Glass foams and glass-ceramic foams exhibit great potential in thermal insulation of buildings, consequently reducing the necessity for heating or cooling, and ultimately contributing to energy saving. In this study, we prepared glass-ceramic foams utilizing silicate glass as starting material and CaCO 3 as foaming agent through a thermochemical process. Foams with varying degrees of relative crystallinity were produced by controlling temperature and duration of isothermal heat treatment. The foaming mechanism in the glass-ceramics was discussed by analyzing how the heat flow, mass, and volume evolve within the powder mixture during dynamic heating. The crystallization in glass did not show any clear trend on the compressive strength of glass foams. On the other hand, the thermal conductivity of the glass-ceramic foams increases with increasing relative crystallinity. The calculated solid thermal conductivity exhibited a minimum at low relative crystallinity (<20 %). These findings are crucial for designing high performance glass-ceramic foams for thermal insulation, potentially also for fabricating glass-ceramic foams using waste glasses. [ABSTRACT FROM AUTHOR]

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Polyacrylonitrile (PAN) nascent fibers were spun in a mixture of dimethyl sulfoxide (DMSO) and water. As the DMSO mass fraction (WDMSO) or temperature (TS) of the solution increased, the crystallinity and the modulus of PAN fibers first increased and then decreased. At WDMSO < 75% or TS < 45 °C, increases in the WDMSO and TS resulted in the formation of ordered crystal structures, and the crystallinity and the modulus of the PAN fibers improved. At WDMSO > 75% or TS > 45 °C, increases in the WDMSO and TS facilitated formation of a chaotic internal structure. Furthermore, the crystallinity and modulus of the nascent fiber decreased because the aqueous DMSO solution dissolved PAN. The moduli of the PAN fibers depended strongly on the crystallinity. The fiber outer layer was the first part of the fiber to encounter the DMSO aqueous solution, and material exchange between DMSO in the fiber and water in the DMSO aqueous solution occurred more readily than in the core. This resulted in a higher degree of coagulation and a larger modulus. When WDMSO was 75% and TS was 45 °C, the PAN fibers had the highest crystallinity (61%), highest modulus (28.5 GPa), and smallest modulus difference (5 GPa) between the PAN fiber outer layer and core. [ABSTRACT FROM AUTHOR]

Fresh mulberry is a soft and juicy fruit with no protective layer on the skin, limiting its storage and transportation. Nanocellulose (NCC) and chitosan (CS) films have extensive potential in packaging due to their high–gas barrier, excellent mechanical, and antibacterial properties. Therefore, this study aimed to improve the storage resistance of fresh mulberries using laminated cellulose nanocrystal/CS (NCC/CS) composite coatings. The relationships between film microstructure, gas barrier characteristics, and mulberry storage properties were investigated. The results showed that the prepared NCC had a crystallinity of 80.40% with the length of 382.53 ± 42.40 nm and the diameter of 10.97 ± 4.71 nm. It was capable of forming a uniform film with an oxygen transmittance rate of 23.97 × 103 cm3/(cm2 day) and a solubility rate of 0.0025 g/min. The laminated NCC/CS composites had a denser structure, a lower oxygen transmittance rate of 0.62 × 103 cm3/(cm2 day), and antibacterial properties, as indicated by an inhibition circle measuring 5.3–6.2 mm in diameter. During storage, NCC/CS-coated mulberries displayed a slowly reducing sensory quality, lower mass loss rate, and lower rotting rate. After 10 days, compared with the uncoated mulberry, the soluble solid content in NCC/CS-coated mulberries decreased from 10.9 to 8.73%, soluble glucose content increased from 5.24 to 6.2%, and malondialdehyde content increased from 20.43 to 37.95%. The coating provided mechanical protection and offered superior oxygen barrier properties and a denser microstructure, leading to a weaker respiratory function and better mulberry storage. The findings of this study provided a novel approach for the practical application of NCC materials. [ABSTRACT FROM AUTHOR]

The challenges of forming a crystalline phase within 45S5 Bioglass® (45% SiO2-24.5% CaO-24.5% Na2O-6% P2O5 mol%) and its subsequent influence on the bioactivity of the bioglass were studied in this research. Bioglasses were sintered at 1400, 750, and 550 °C, using both melting and sol-gel methods. The different responses of bioglasses to different sintering temperatures were revealed. Particularly, increased crystallinity was observed in sol-gel-derived bioglass sintered at 750 °C, indicating a denser and more ordered structure. This crystalline architecture facilitated enhanced bioactivity, as demonstrated by increased hydroxyapatite deposition when immersed in simulated body fluid (SBF). Furthermore, superior mechanical properties and biocompatibility were achieved with this temperature regime, making it a prime candidate for bone regeneration applications. The bioglass sintered at 750 °C exhibited an accelerated degradation rate associated with its porosity, potentially contributing to faster material resorption in vivo. Its antibacterial efficacy against E. coli and S. aureus was also noted, and in vitro studies with MTT assay confirmed that the optimized sol-gel bioglass meets biocompatibility standards. These findings highlight the potential of fine-tuning the sintering temperature to modulate the crystallinity of bioglasses, thereby enhancing their application scope in bone tissue engineering. Highlight: Bioglasses were sintered at three different temperatures: 550, 750, and 1400 °C. The sol-gel-derived sintered at 750 °C exhibited increased crystallinity. This increased crystallinity resulted in enhanced mechanical properties, biocompatibility, antibacterial efficacy, and accelerated degradation. [ABSTRACT FROM AUTHOR]

We use the crystallinity of hydrated silica, represented by the 1.4 μm absorption position in orbiter spectroscopic data, as a proxy for the longevity of water–rock interaction in the Syrtis Major region. Geological maps and crater size–frequency distribution analyses are employed to contextualize mineral detections and estimate surface ages. Hydrated silica is detected within two distinct geological units: a younger "volcanic terrain" (vt) unit (∼2.4 Ga) and an older "highland terrain" (ht) unit (3.5–3.7 Ga). Hydrated silica in the vt unit typically has a band position <1.41 μm, consistent with amorphous opal‐A, suggesting these younger terrains have experienced limited interaction with water. In contrast, hydrated silica in the older highlands typically has a band position >1.41 μm, indicating opal‐CT, suggesting that these deposits have had more time to interact with water, while also producing accessory minerals such as kaolinite and Fe/Mg phyllosilicates. Plain Language Summary: This study explores the interactions between water and rocks in a region on Mars known as Syrtis Major by investigating a mineral‐like substance called hydrated silica. The structure of hydrated silica helps us estimate the extent of water interaction and its effects on the rocks. We used satellite data to locate this mineral across Syrtis Major and infer its crystal structure. Furthermore, we developed detailed geological maps and estimated surface ages to understand the geological context. We found that hydrated silica is located in two different types of areas: (a) a younger volcanic region; and (b) an older highland region. In the younger volcanic areas, it appears that less crystalline hydrated silica formed by interaction with small amounts of water, possibly during later volcanic activity. In the older highlands, more crystalline hydrated silica likely interacted with water for a longer duration or in larger amounts. This information aligns with the idea that the older highlands experienced more extensive or long‐lasting interactions with water compared to the younger volcanic regions. It provides insights into different wet periods in Mars' past, aiding our understanding of the planet's geological history and the role water played in shaping its surface. Key Points: We analyzed the crystallinity of hydrated silica in Syrtis Major to infer the extent and longevity of water–rock interactionAmorphous silica is found in young volcanic terrains within Nili and Meroe Paterae and more crystalline silica in the older highlandsOlder highland regions likely underwent a longer interaction with water compared to younger volcanic terrains [ABSTRACT FROM AUTHOR]

This study mainly focused on the hot-stretching-induced oriented crystallization structure of isotactic polypropylene (iPP) granules specialized for capacitance films (i. e. electrical grade iPP). A series of characterization tools, including differential scanning calorimetry, wide-angle X-ray diffraction, two-dimensional small-angle/wide-angle X-ray scattering, and dynamic mechanical analysis, were employed to determine the long-period spacing, orientation degree, crystallinity, melt point and chain relaxation behavior of iPP. The stretching deformation resulted in a highly oriented fibrillar morphology. A strain-induced crystallization enhancement was observed, in which both of the orientation degree and crystallinity increased continuously with an increasing in the strain. Two types of lamellae with thicker or thinner thicknesses were newly formed during the hot-stretching process. The thicker one can be attributed to the melt-recrystallization mode, while the thinner one is ascribed to the strain-induced crystallization mechanism. The dependence of strain on their crystallinity and melt point seemed to be weak. Moreover, the electric density difference between the amorphous and crystalline phases decreased with an increase in the strain, and meanwhile the chain relaxation temperatures related to different condensed states became close to each other. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) electrocatalysis is an area of increasing interest for the in‐situ production of H2O2 or the development of energy‐related devices such as hydrogen fuel cells. Although pyrolyzed catalysts still offer the best performances to date with reference to the organic‐based catalysts, metal‐free and non‐pyrolyzed covalent organic frameworks (COFs) stands out as promising alternatives candidates due to their favourable characteristics such as crystallinity, porosity, and organic composition, allowing the study of structural‐property relationships. Herein, we present the design principles and recent advances in COFs‐based ORR electrocatalysts, demonstrating how composition influences the activity and electronic pathway of the oxygen reduction process. [ABSTRACT FROM AUTHOR]

Highlights Polymer nanocomposites boast complex microstructures with instant control of final performance, including mechanical strength, thermal stability, and crystallinity. Although tremendous studies have been devoted to understanding the structure–property relation of polymer nanocomposites, the effect of simultaneous nanomaterial contents on binary polymers remains unclear. Here, we report how the microstructure and rheological characteristics are subject to change upon adding a hybrid multi‐walled carbon nanotube (CNT) and graphene nanoplatelet (GNP). We choose a refined binary system based on polypropylene (PP) as a commodity polymer with proven long‐standing applications, alongside ethylene‐butylene copolymer (EBC) with a random ethylene and butylene monomers orientation for better impact strength acquisition. Rheology and microscopy imaging support an adequate dispersion of both materials across the PP/EBC blend, similar to when a single‐particle nanocomposite is examined. Beyond investigating the heterogeneous nucleation role of CNT and GNP, the crystallinity rate and the half‐time parameter for completing the ordered transformation are calculated using the Avrami equations. The thermal stability as well as the mechanical properties of all nanocomposites reveal improved resilience under heat and external stress, leading to a rising trend in decomposition temperature, tensile strength, and modulus. Synergistic effect of hybrid CNT and GNP on the thermal stability of PP/EBC. The impact of hybrid CNT and GNP on crystallization kinetics. Improvement of the mechanical performance with CNT/GNP loading. Role of PP‐g‐MA on the dispersion and distribution of CNT and GNP. [ABSTRACT FROM AUTHOR]

Cellulose nanomaterials are derived from the most abundant biopolymer on earth, and are gaining importance in the shift from oil-based materials to sustainable alternatives. To facilitate this, sustainable methods to modify these renewable nanostructured materials must be explored, as surface modifications are prerequisite for many nanocellulose applications. Here, we present a solvent-free method for the surface modification of cellulose nanocrystals, encompassing mechanochemistry to convert uncharged or charged CNCs to tosylated CNCs, and for the subsequent versatile nucleophilic substitution with amines and esters. Systematic screening of the reaction parameters revealed key variables - milling time, base type and amount, for tosylation to take place during 60 minutes of ball-milling without major changes to CNC morphology and crystallinity. Both step-wise and one-step in situ nucleophilic substitution of the tosyl CNCs was successful with amine and ester modification. Our results demonstrate how fine-tuning the parameters of solvent-free methods can lead to fast and environmentally benign reactions on cellulose nanomaterials while retaining their structure on the nanoscale. [ABSTRACT FROM AUTHOR]

Hydrated nickel hydroxides with partial aluminum substitution were synthesized using the conventional coprecipitation and soft chemistry methods. The soft chemistry derived sample showed better reversibility owing to the low activity for oxygen evolution during charging. Operando X-ray diffraction indicated the increased interlayer distance and decreased crystallinity during discharging caused by water accommodation. [ABSTRACT FROM AUTHOR]

Achieving high crystallinity levels, dense, crack-free microstructures with near-stoichiometric phase composition and controlled secondary phase formation are crucial for enhancing the performance of environmental barrier coatings (EBCs). To investigate the impact of APS process parameters on the as-sprayed crystallinity, microstructure, and phase composition of Yb 2 Si 2 O 7 EBCs, various spraying conditions were explored by adjusting torch power, nozzle size, powder feedrate, stand-off distance, and adding a shroud attachment to the torch. The velocity of particles controlled the density of the EBCs by an interplay between deposition efficiency and splat flattening ratios. Increasing nozzle size from 5/16″ to 1/2″ reduced particle velocity by up to 40 %, resulting in improved deposition efficiencies, porosity levels and coating thickness. However, larger nozzles led to higher silicon evaporation and up to 8 wt% more stable Yb 2 SiO 5 (I2/a) secondary phase was formed. Increasing the stand-off distance from 50 mm had minimal effect on microstructure, but metastable Yb 2 SiO 5 (P 21/c) was detected (up to 9 wt%) at longer stand-off distances of 100 and 150 mm. Raising the powder feedrate from 15 gr/min to 60 gr/min improved deposition efficiency (up to 9 %) and density (up to 15 %) of EBCs, yet resulted in higher silicon-depleted phase formation (up to 12 wt%). Adding a shroud to the torch nozzle exit led to severe silicon evaporation and formation of up to 42 wt% and 6 wt% of Yb 2 SiO 5 (I2/a) and Yb 2 O 3 , respectively. Moreover, due to the shroud's funnelling effect on smaller particles as well as particle overheating, porous microstructures with up to 28 % porosity levels were formed. High levels of crystallinity (∼75–91 %) were achieved in the as-sprayed condition for all the coatings, indicating real-time crystallization during spraying in all the spraying conditions. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA), a commonly used material for bone repair, can enhance its biological properties through the modulation of its crystallinity. Exploring the variations in physicochemical and biological properties associated with different degrees of crystallinity is crucial for advancing the applications of HA. In this study, stoichiometric nano-apatite precursors were initially synthesized using chemical precipitation. Subsequently, four groups of HA ceramics with varying degrees of crystallinity (24 %, 42 %, 72 %, 100 %) were produced by adjusting the calcination temperature, as confirmed through comprehensive characterizations. A systematic investigation was then conducted to examine the impact of crystallinity on the physicochemical, cytological, and in vivo osteogenic properties of HA ceramics, elucidating the influence of crystallinity on the osteogenic potential of HA. Results indicated that higher crystallinity in HA ceramics enhanced mechanical strength and hardness while reducing surface roughness, hydrophilicity, and protein affinity. Cytological studies revealed that decreased crystallinity led to lower cell proliferation rates but facilitated cell adhesion, spreading, and increased expression of osteogenic genes. Moreover, cell experiments with extracts further supported the significant role of surface properties of HA ceramics in modulating cell behavior. In vivo osteogenic assays demonstrated that reduced crystallinity notably stimulated new bone formation. Overall, by integrating the results of in vitro and in vivo experiments, it can be concluded that reducing the crystallinity of HA ceramics, the biological properties of HA ceramics can be significantly enhanced while maintaining a certain level of mechanical strength, such as HA2 group (42 % crystallinity). This study highlights the substantial impact of crystallinity and surface characteristics of HA ceramics on cell behavior, offering valuable insights and strategies for enhancing and optimizing bone repair materials in future applications. [ABSTRACT FROM AUTHOR]

In this work, pine and birch wood were modified by graphene oxide using a single vacuum impregnation method. The research results indicate that the impregnation of wood with graphene oxide increases the crystallinity of cellulose in both pine and birch wood, and the increase in crystallinity observed in the case of birch was more significant than in the case of pine. FT-IR analyses of pine samples impregnated with graphene oxide showed changes in intensity in the absorption bands of 400–600, 700–1500 cm−1, and 3200–3500 cm−1 and a peak separation of 1102 cm−1, which may indicate new C-O-C connections. In the case of birch, only some differences were noticed related to the vibrations of the OH group. The proposed modification also affects changes in the color of the wood surface, with earlywood containing more graphene oxide than latewood. Analysis of scanning electron microscope images revealed that graphene oxide adheres flat to the cell wall. Considering the differences in the anatomical structure of both wood species, the research showed a statistically significant difference in water absorption and retention of graphene oxide in wood cells. Graphene oxide does not block the flow of water in the wood, as evidenced by the absorbability of the working liquid at the level of 580–602 kg/m3, which corresponds to the value of pure water absorption by wood in the impregnation method using a single negative pressure. In this case, higher graphene oxide retention values were obtained for pine wood. [ABSTRACT FROM AUTHOR]

Iron (Fe) removal is a critical step in the hydrometallurgical zinc (Zn) extraction process. Hematite, a stable Fe precipitate, offers an environmentally friendly option that complies with environmental protection standards. While existing research primarily focuses on hematite process technology, there is a lack of studies on how ions in ZnSO4 leaching solutions affect Fe removal efficiency and hematite particle size distribution. This study investigated the influence of manganese II (Mn(II)) and magnesium II (Mg(II)) concentrations and temperature on both Fe removal efficiency and hematite particle size distribution in ZnSO4 leaching solution. The results indicated that at various temperatures, the highest Fe removal efficiency occurred with an initial Mn(II) concentration of 10 g/L and an Mg(II) concentration of 15 g/L. As the concentrations of Mn(II) and Mg(II) as well as temperature increased, FeSO₄ crystallization also increased, which adversely affected hematite precipitation. The average particle size of hematite decreases from 300 to 100 nm, resulting in a more uniform particle size distribution, which correlated with the homogeneous solution saturation precipitation mechanism. However, the number of rod-shaped, regular small particles decreases, while the number of irregular, blocky particles increased. [ABSTRACT FROM AUTHOR]

Temperature-dependent nano SiC obtained from the polymer-derived ceramics method was used to modify ZrC coating by supersonic atmosphere plasma spraying. The crystallinity and grain size of SiC increased with increasing annealing temperatures. SiC annealed at 1400 °C exhibited the lowest crystallinity of 48.4 %, which led to massive re-pyrolyzing gas spillage from the modified ZrC coating during ablation, causing penetrating cracks. SiC annealed at 2100 °C exhibited the largest grain size of 190.4 nm, which could produce locally massive amounts of SiO 2 , accelerating the sintering of ZrO 2 in the coating and leaving maximum residual stress. SiC annealed at 1800 °C possessed a medium crystallinity of 81.5 % and a grain size of 12.2 nm, which was favorable to improve the ablation resistance of ZrC coating for forming fine-grained ZrO 2 scale with minimum residual stress. Our work provides a novel perception of the microstructure-property relationship for ablation-resistant coating under extreme conditions. [ABSTRACT FROM AUTHOR]

This study employs coaxial electrospinning to fabricate core‐sheath fibers composed of crystalline poly(L‐lactide) (PLLA) in the core and amorphous polystyrene (PS) in the sheath. The fibers undergo cold crystallization at temperatures either below (hard confinement) or above (soft confinement) the glass transition temperature of PS. These conditions are employed to investigate the crystallization behavior of PLLA under multiple confinement types. The electrospinning of PLLA fibers results in the development of coexisting α‐ and α′‐form crystals. The coaxial electrospinning process enhances the extent of chain stretching of PLLA through the PS solution in the outer layer, thereby promoting the close packing of PLLA chains and facilitating the formation of α crystals. Crystallization within soft confinement enables PLLA chains to relax, leading to an increased population of α crystals; this phenomenon is not observed in electrospun single PLLA fibers. A comparison of the crystal parameters in core‐sheath and single PLLA fibers reveals that the crystallite size and the degree of crystallinity are considerably higher in unconfined single PLLA fibers than in confined core‐sheath fibers. The encapsulation of PLLA into the fiber core strongly inhibits the chain movement of PLLA, resulting in a decrease in PLLA crystallizability. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is chosen as a coating material on industrial Kraft paper substrates to impart a barrier against air, grease, and water. This is an excellent initiative to replace the existing non-biodegradable and petroleum-based coating materials used in many industrial products such as packaging and coated abrasives. In this study, the effect of the crystallinity of PLA on its barrier properties is evaluated. Initially, amorphous and semi-crystalline PLA (sc-PLA) are compared for properties such as coating weight, gloss, heat seal strength, air resistance, grease resistance, contact angle, water resistance, and water vapor transmission rate (WVTR). Sc-PLA is observed to show better barrier properties than its amorphous counterpart. To understand if the barrier properties imparted by a biodegradable coating material on Kraft paper will improve with an increase in crystallinity, sc-PLA is compared to a more crystalline biodegradable polymer, polycaprolactone (PCL). The results indicate that PCL shows compromised results with respect to sc-PLA as a barrier coating material. The theory behind this effect is discussed, and the two bio-based polymers, namely, PLA and PCL, are also comparatively evaluated against the conventionally used synthetic barrier coating materials, acrylic, and varnish, on identical paper substrates under identical process conditions. SEM and DSC analyses on amorphous PLA, sc-PLA, and PCL coatings are also conducted to decipher the microstructural traits of these macromolecules. Sc-PLA serves as an ideal barrier coating material on Kraft paper, and it possesses better hydrophobic properties than untreated, PCL-treated, acrylic-treated, or varnish-treated Kraft paper substrates. [ABSTRACT FROM AUTHOR]

Antimony selenosulfide Sb2(SxSe1−x)3 is featured as a stable, environment‐friendly, and low‐cost light‐harvesting material with a tunable bandgap in the range of 1.1–1.8 eV, satisfying the requirement of indoor photovoltaics (IPVs). Up to now, the certified efficiency of Sb2(SxSe1−x)3 solar cell with 1.45 eV bandgap has broken 10% under standard illumination (AM1.5G). However, this bandgap is not suitable for IPVs in terms of spectral matching. Herein, for the first time, the effect of optical bandgap of Sb2(SxSe1−x)3 on photovoltaic performance of the devices under AM1.5G and indoor light conditions is studied systematically. It is discovered that although an appropriate Se/S atomic ratio is beneficial for improving the crystallinity of Sb2(SxSe1−x)3 film and passivating the trap states, the band gap remains a key factor in determining the suitability of this material for IPVs. As a result, solar cells based on Sb2S3 with a large bandgap of 1.74 eV achieve an optimal efficiency of 20.34% under 1000 lux indoor illumination. Moreover, a high IPV efficiency of over 16% can still be maintained within a wide bandgap range from 1.5 to 1.7 eV, demonstrating the great potential of Sb‐based chalcogenide as a light‐harvesting material for IPVs. [ABSTRACT FROM AUTHOR]