Macroscopic Structure Research Articles

Effect of B2O3 content on the structural and optical properties of (Ba0.85Ca0.15) (Ti0.9Zr0.1)O3 glass

This study explores the structural and optical properties of (Ba0.85Ca0.15) (Ti0.9Zr0.1)O3 system mixed with B2O3. The samples with the composition xB2O3 + (100-x) (Ba0.85Ca0.15) (Ti0.9Zr0.1)O3 (where x = 5, 10, 20, 30 and 40 mol. %) were prepared using the melting quenching technique to form borate-based glass containing BaO, CaO, ZrO2 and TiO2 (BBCZT). X-ray diffraction analysis confirmed the amorphous nature of the prepared samples. The macroscopic structure of the glasses was assessed from the density measurements determined through Archimedes' principle, while information regarding the atomic structural units and vibrational modes were obtained from Infrared measurements. Increasing the B2O3 content led to variation of the relative intensity of these modes together with a decrease (increase) in density (molar volume), indicating a less dense and open-structure for the glass network. The absorption spectra showed absorption bands associated with the optical transitions B22g→B21g and B22g→A21g of Ti3+ ions occupying distortion octahedral sites (TiOh3+) in the glass matrix. The ligand field strength (10Dq), optical energy gap (Eopt), Urbach's energy (ΔE), and nonlinear optical properties (NLO) were calculated in the study.

Elucidating chirality transfer in liquid crystals of viruses.

Chirality is ubiquitous in nature across all length scales, with major implications spanning fields from biology, chemistry and physics to materials science. How chirality propagates from nanoscale building blocks to meso- and macroscopic helical structures remains an open issue. Here, working with a canonical system of filamentous viruses, we demonstrate that their self-assembly into chiral liquid crystal phases quantitatively results from the interplay between two main mechanisms of chirality transfer: electrostatic interactions from the helical charge patterns on the virus surface, and fluctuation-based helical deformations leading to viral backbone helicity. Our experimental and theoretical approach provides a comprehensive framework for deciphering how chirality is hierarchically and quantitatively propagated across spatial scales. Our work highlights the ways in which supramolecular helicity may arise from subtle chiral contributions of opposite handedness that act either cooperatively or competitively, thus accounting for the multiplicity of chiral behaviours observed for nearly identical molecular systems.

Deep learning with diffusion MRI as in vivo microscope reveals sex-related differences in human white matter microstructure

Biological sex is a crucial variable in neuroscience studies where sex differences have been documented across cognitive functions and neuropsychiatric disorders. While gross statistical differences have been previously documented in macroscopic brain structure such as cortical thickness or region size, less is understood about sex-related cellular-level microstructural differences which could provide insight into brain health and disease. Studying these microstructural differences between men and women paves the way for understanding brain disorders and diseases that manifest differently in different sexes. Diffusion MRI is an important in vivo, non-invasive methodology that provides a window into brain tissue microstructure. Our study develops multiple end-to-end classification models that accurately estimates the sex of a subject using volumetric diffusion MRI data and uses these models to identify white matter regions that differ the most between men and women. 471 male and 560 female healthy subjects (age range, 22–37 years) from the Human Connectome Project are included. Fractional anisotropy, mean diffusivity and mean kurtosis are used to capture brain tissue microstructure characteristics. Diffusion parametric maps are registered to a standard template to reduce bias that can arise from macroscopic anatomical differences like brain size and contour. This study employ three major model architectures: 2D convolutional neural networks, 3D convolutional neural networks and Vision Transformer (with self-supervised pretraining). Our results show that all 3 models achieve high sex classification performance (test AUC 0.92–0.98) across all diffusion metrics indicating definitive differences in white matter tissue microstructure between males and females. We further use complementary model architectures to inform about the pattern of detected microstructural differences and the influence of short-range versus long-range interactions. Occlusion analysis together with Wilcoxon signed-rank test is used to determine which white matter regions contribute most to sex classification. The results indicate that sex-related differences manifest in both local features as well as global features / longer-distance interactions of tissue microstructure. Our highly consistent findings across models provides new insight supporting differences between male and female brain cellular-level tissue organization particularly in the central white matter.

Beyond Frequency Bands: Complementary-Ensemble-Empirical-Mode-Decomposition-Enhanced Microstate Sequence Non-Randomness Analysis for Aiding Diagnosis and Cognitive Prediction of Dementia.

Exploring the spatiotemporal dynamic patterns of multi-channel electroencephalography (EEG) is crucial for interpreting dementia and related cognitive decline. Spatiotemporal patterns of EEG can be described through microstate analysis, which provides a discrete approximation of the continuous electric field patterns generated by the brain cortex. Here, we propose a novel microstate spatiotemporal dynamic indicator, termed the microstate sequence non-randomness index (MSNRI). The essence of the method lies in initially generating a sequence of microstate transition patterns through state space compression of EEG data using microstate analysis. Following this, we assess the non-randomness of these microstate patterns using information-based similarity analysis. The results suggest that this MSNRI metric is a potential marker for distinguishing between health control (HC) and frontotemporal dementia (FTD) (HC vs. FTD: 6.958 vs. 5.756, p < 0.01), as well as between HC and populations with Alzheimer's disease (AD) (HC vs. AD: 6.958 vs. 5.462, p < 0.001). Healthy individuals exhibit more complex macroscopic structures and non-random spatiotemporal patterns of microstates, whereas dementia disorders lead to more random spatiotemporal patterns. Additionally, we extend the proposed method by integrating the Complementary Ensemble Empirical Mode Decomposition (CEEMD) method to explore spatiotemporal dynamic patterns of microstates at specific frequency scales. Moreover, we assessed the effectiveness of this innovative method in predicting cognitive scores. The results demonstrate that the incorporation of CEEMD-enhanced microstate dynamic indicators significantly improved the prediction accuracy of Mini-Mental State Examination (MMSE) scores (R2 = 0.940). The CEEMD-enhanced MSNRI method not only aids in the exploration of large-scale neural changes in populations with dementia but also offers a robust tool for characterizing the dynamics of EEG microstate transitions and their impact on cognitive function.

Making titanium alloys ultrahigh strength and toughness synergy through deformation kinks-mediated hierarchical α-precipitation

Titanium alloys engineered in structural applications achieve ultrahigh strength primarily through precipitation strengthening of secondary α-phase (αs) during aging, while they often experience compromised ductility and toughness due to traditional strength-toughness tradeoff. In this study, we propose a novel strategy to address this conflict by introducing deformation kinks prior to conventional cold rolling (CR) and aging processes. These kinks are produced by cold forging (CF) to create macroscopic lamellar structures in β-grains, which alter strain partitioning during subsequent CR and ultimately tailor αs-precipitation upon aging. As a result, an ultrafine duplex (αe + β)-structure is formed within kink interiors, while hierarchical αs-precipitates are generated in the external β-matrix. This unique microstructure effectively enhances dislocation activity, promotes uniform plastic strain distribution and impedes crack propagation. Consequently, a simple Ti-V binary titanium alloy exhibits exceptional properties with ultrahigh strength ∼1636 MPa, decent ductility ∼5.4 % and appreciable fracture toughness ∼ 36.1 MPa m½. The synergetic properties surpass those obtained through traditional CR and aging processes for the alloy and even outperform numerous multielement engineering titanium alloys reported in literature. Our findings open up a new avenue for overcoming the strength-toughness tradeoff of ultrahigh-strength titanium alloys, and also offer a facile production route towards structural materials for advanced performance.

Briefing: Selective laser sintering technology to print walnut shell/phenolic resin new biomass-based porous electrode

In this paper, porous carbon electrodes were prepared by using walnut shell and phenolic resin as matrix materials, combined with selective laser sintering (SLS) technology and carbonization process. The effects of different ratios and temperatures on the macroscopic morphology, graphitization degree, electrical conductivity and pore structure of the carbonized parts were investigated. The results show that the lower proportion of walnut shell and the higher carbonization temperature increase the degree of graphitization. High temperature has a significant effect on the conductivity. The conductivity at 1000 °C is 7.5197 S·cm−1, which is 752 % higher than that at 600 °C, while the conductivity at 30 % walnut shell content is only 75.4 % higher than that at 50 %. This study provides a new reference for the preparation of carbon electrodes with complex shape and structure by biomass consumables.

A deviatoric couple stress Mindlin plate model and its degeneration

Based on the classical couple stress theory, the deviatoric couple stress theory (DCST), where both couple stress and curvature tensors are traceless, is developed. The deviatoric couple stress Mindlin plate is established based on a new hypothesis of the vanishing curvature of the transverse normal, and the governing equations and associated boundary conditions of the simplified size-dependent Mindlin plate are respectively derived by the principle of virtual work. In the absence of couple stresses, a simplified Mindlin plate model between the classical Kirchhoff plate model and classical Mindlin plate model is derived. To illustrate the simplified DCST-based Mindlin plate model, the static bending and free vibration of rectangular plates are studied. The dependence of the length scale parameter and curvature ratio on the deflection, rotation and natural frequency is analyzed. The numerical results show that the consideration of couple stresses and curvatures hardens the stiffness of the microstructure, resulting in a decrease in its deflection and rotation compared with that of the macroscopic structure under the same conditions, while the natural frequency increases, which is consistent with the size effect observed in experiments.

Direct FE[formula omitted] failure prediction of fused-filament fabricated parts

The rapid development of additive manufacturing technology and the consequential microstructural variations have brought the simulation aspects into focus. To capture an accurate mechanical response, multiscale methods are used to determine the macroscopic constitutive behaviour. Among these methods, the recently introduced Direct FE2 (DFE2) technique has shown some success in predicting material behaviour via the direct incorporation of representative microstructure volumes into the macroscopic structure. The present study highlights the predictive modelling capabilities of DFE2 linked with an element elimination technique (EET) in investigating the performance of fused-filament fabrication (FFF) samples under tension and compression. Parts were manufactured by FFF with various raster angles to vary the failure characteristics. Their mechanical responses and fracture behaviours were simulated by DFE2 and benchmarked against conventional finite element (FE) analysis, highlighting that the results of DFE2 were competitive against FE. Most importantly, the combination of EET with DFE2 resulted in predictive insights regarding changes in the failure surface for samples with varying raster angles.

A Tape-Wrapping Strategy towards Electrochemical Fabrication of Water-Dispersible Graphene.

Graphene has achieved mass production via various preparative routes and demonstrated its uniqueness in many application fields for its intrinsically high electron mobility and thermal conductivity. However, graphene faces limitations in assembling macroscopic structures because of its hydrophobic property. Therefore, balancing high crystal quality and good aqueous dispersibility is of great importance in practical applications. Herein, we propose a tape-wrapping strategy to electrochemically fabricate water-dispersible graphene (w-Gr) with both excellent dispersibility (~4.5 mg/mL, stable over 2 months), and well-preserved crystalline structure. A large production rate (4.5 mg/min, six times faster than previous electrochemical methods), high yield (65.4% ≤5 atomic layers) and good processability are demonstrated. A mechanism investigation indicates that the rational design of anode configuration to ensure proper oxidation, deep exfoliation and unobstructed mass transfer is responsible for the high efficiency of this strategy. This simple yet efficient electrochemical method is expected to promote the scalable preparation and applications of graphene.

Tunable Macroscopic Alignment of Self-Assembling Peptide Nanofibers.

Progress in the design and synthesis of nanostructured self-assembling systems has facilitated the realization of numerous nanoscale geometries, including fibers, ribbons, and sheets. A key challenge has been achieving control across multiple length scales and creating macroscopic structures with nanoscale organization. Here, we present a facile extrusion-based fabrication method to produce anisotropic, nanofibrous hydrogels using self-assembling peptides. The application of shear force coinciding with ion-triggered gelation is used to kinetically trap supramolecular nanofibers into aligned, hierarchical macrostructures. Further, we demonstrate the ability to tune the nanostructure of macroscopic hydrogels through modulating phosphate buffer concentration during peptide self-assembly. In addition, increases in the nanostructural anisotropy of fabricated hydrogels are found to enhance their strength and stiffness under hydrated conditions. To demonstrate their utility as an extracellular matrix-mimetic biomaterial, aligned nanofibrous hydrogels are used to guide directional spreading of multiple cell types, but strikingly, increased matrix alignment is not always correlated with increased cellular alignment. Nanoscale observations reveal differences in cell-matrix interactions between variably aligned scaffolds and implicate the need for mechanical coupling for cells to understand nanofibrous alignment cues. In total, innovations in the supramolecular engineering of self-assembling peptides allow us to decouple nanostructure from macrostructure and generate a gradient of anisotropic nanofibrous hydrogels. We anticipate that control of architecture at multiple length scales will be critical for a variety of applications, including the bottom-up tissue engineering explored here.

Drilling- and coring-induced artefacts in poorly indurated clays

Macroscopic and microscopic drilling-induced deformation structures were documented in cores of Ypresian Ieper Group and Rupelian Boom Formation clays using macro-polished slabs and polarizing microscopy of thin sections. The cores were recovered in north Belgium from a depth of a few hundred metres by pushing a steel barrel with a cutting shoe into the non-indurated clays that are in a ductile to brittle transition state. The outer border of the clay cores was bent downwards due to the pushing action. The geometry of the drilling-induced fractures can be described as vertically stacked axisymmetrical conical fractures complexed by a general concave and undulating shape, and by fractures splaying from other fractures. At the microscopic scale (2D), the fractures are micro-faults that produce a breccia texture and which consist of thin planes, lines in 2D, of orientated clay minerals. The preferred orientation of these clay minerals in the fractures point to shear movement and explain the shiny appearance of these slickenside-like fractures when viewed in 3D. The micro-faults produce clay domains tilted with respect to each other. Recognizing exclusively drilling-induced structures helps in the selection of cores and core fragments for further laboratory testing, and may be of help in distinguishing them from regional faults or fracture systems in homogeneous clays. Thematic collection: This article is part of the Sustainable geological disposal and containment of radioactive waste collection available at: https://www.lyellcollection.org/topic/collections/radioactive

Probing the Molecular and Macroscopic Structure of Solid Solutions by Dynamic Nuclear Polarization (DNP) Enhanced 13C and 15N Solid-State NMR Spectroscopy.

Crystallization is a widely used purification technique in the manufacture of active pharmaceutical ingredients (APIs) and precursor molecules. However, when impurities and desired compounds have similar molecular structures, separation by crystallization may become challenging. In such cases, some impurities may form crystalline solid solutions with the desired product during recrystallization. Understanding the molecular structure of these recrystallized solid solutions is crucial to devise methods for effective purification. Unfortunately, there are limited analytical techniques that provide insights into the molecular structure or spatial distribution of impurities that are incorporated within recrystallized products. In this study, we investigated model solid solutions formed by recrystallizing salicylic acid (SA) in the presence of anthranilic acid (AA). These two molecules are known to form crystalline solid solutions due to their similar molecular structures. To overcome challenges associated with the long 1H longitudinal relaxation times (T1(1H)) of SA and AA, we employed dynamic nuclear polarization (DNP) and 15N isotope enrichment to enable solid-state NMR experiments. Results of solid-state NMR experiments and DFT calculations revealed that SA and AA are homogeneously alloyed as a solid solution. Heteronuclear correlation (HETCOR) experiments and plane-wave DFT structural models provide further evidence of the molecular-level interactions between SA and AA. This research provides valuable insights into the molecular structure of recrystallized solid solutions, contributing to the development of effective purification strategies and an understanding of the physicochemical properties of solid solutions.

In situ preparation and characterization of Cr-MOF-alginates for methylene blue through the adsorption process

One of the increasing environmental worries arises from water pollution caused by synthetic dyes since several colors possess carcinogenic properties. Metal-organic frameworks (MOFs) have attracted considerable attention as adsorbents for removing dyes in wastewater treatment. Nevertheless, the inherent characteristics of MOFs impose limitations on their practical use in terms of recycling, separation, and recovery. To overcome these limitations, MOFs are modified into macroscopic structures. We reported two macroscopic Cr-MOF-Alginate composite beads prepared using the in situ growth method to remove methylene blue from the aqueous solution. The characterization tools confirmed that two different Cr-MOF-Algs formed with different in situ methods and showed distinct MB adsorption. The trials produced the following optimal conditions: an adsorbent dose of 0.3 g, a pH level of 10, a contact length of 120 min, a primary concentration of 10 mgL−1 for MB, and a temperature of 25 °C. In these circumstances, the maximum MB removal percentages reached 90.33 %, 93.42 %, and 94.06 % for Cr-Alg, Cr-BTC/SA-R, and Cr-BTC/SA-A, respectively. Additionally, various isotherms and kinetics implied that the adsorption of MB onto Cr-Alg and Cr-MOF-Alg composite beads occurs through chemisorption and physisorption. Thermodynamic analysis revealed that the adsorption process exhibited an endothermic and spontaneous nature.

Features of topography and macroscopic structure of the digestive organs of the Yemeni chameleon (Chamaeleo calyptratus)

The relevance of this study is conditioned by the lack of detailed information on the structure and topography of the digestive organs of the Yemeni chameleon (Chamaeleo calyptratus). The purpose of this study was to find out the specific features of changes in body weight, topography, and structure of the digestive organs of the Yemeni chameleon, to determine their morphometric parameters in animals from 1 day to 1 year of age. The research material included the tongue, oesophagus, stomach, intestines, liver, and pancreas of chameleons of different sexes of 9 age groups. The data obtained were processed by one-factor analysis of variance (ANOVA). According to the topography, macroscopic structure and surface of the mucous membrane, there are three intestines in the small intestine: duodenum, jejunum, and ileum, and two intestines in the large intestine: the colon with a diverticulum and the rectum, which passes into the cloaca. A feature of the serous membrane of the chameleon intestine is that it is coloured black by melanin. From 1 day to 1 year of age, the body weight of chameleons increased 185.9 times, the snout-vent length (SVL) increased 6.7 times, the length of the digestive tract increased 3.8 times, and the ratio of the length of the digestive tract to SVL decreased from 3.2 to 1.8 times. The most intensive increase in body weight and SVL occurred during the second and third months of life. The relative length of the small intestine in chameleons of different age groups was 65.1- 81.6%, with the longest part being the jejunum. The increase in the morphometric parameters of the stomach, intestines, liver, and pancreas was asynchronous. The most pronounced changes in their relative weight were determined in animals of 2-3 months of age. The obtained materials supplement and clarify the information on the topography and structure of the digestive organs of the Yemeni chameleon, and therefore they will be useful in X-ray and ultrasound examination during veterinary manipulations

Spontaneous Compositional-Interfacial Co-Modification Engineering via Ion Exchange Reaction Between Perovskite and Electron-Transporting Layer for Exceptionally Long-Term Stability of Photovoltaics.

The long-term stability of perovskite solar cells (PSCs) is still challenging for commercialization and mainly linked to the life span of perovskite films. Herein, a spontaneous compositional-interfacial co-modification strategy is developed based on the ion exchange reaction by introducing ammonium hexafluorophosphate (NH4PF6) into antisolvent to form gradient structures through a simple one-step solvent engineering. With the assistance of the ion exchange reaction, NH4PF6 forms a multifunctional structure to protect perovskite films from both internal and external factors for the exceptionally long-term stability of photovoltaics. The reason for this is linked to the high hydrophobicity of NH4PF6 for preventing H2O invasion, suppressing ion migration by forming hydrogen bonding, and reducing perovskite defects. The resulting unencapsulated devices show exceptionally long-term stability under standardized the International Summit on Organic Photovoltaic Stability (ISOS) protocols, with over 94%, 81%, and 83% retained power conversion efficiencies after aging tests under N2 (ISOS-D-1I), ambient air (ISOS-D-1), and 85°C (ISOS-D-2I) for 14016, 2500, and 1248h, respectively. These performances compare well with the state-of-the-art stability of inverted PSCs. Further investigations are conducted to study the evolution of macroscopic morphology and microscopic crystal structure in aged perovskite films, aiming to provide evidence supporting the aforementioned improvements in stability.

Multi-layer shearing induced high orientation of graphene oxide sheets towards high-performance macrostructures

The orientation of graphene nanosheets in microstructures is directly related to the mechanical properties and thermal conductivity of graphene-based macrostructures. However, efficient and scalable modulation of the orientation of 2D graphene nanosheets remains challenging. Herein, a simple and effective approach was proposed by introducing a multi-layer shearing field in thick graphene oxide (GO) gel coatings to improve the total orientation of GO films. Hydrodynamic simulations were performed via the lattice-Boltzmann method to reveal the microscale mechanism of the flow profile in improving the orientation of GO nanosheets. The result was experimentally verified by fast Fourier transform (FFT) of the cross-section scanning electron microscope (SEM) images of freeze-dried GO films and wide-angle X-ray scattering (WAXS) patterns of 16 various samples under different shearing line distances, velocities, and GO concentrations. The obtained GO films exhibit high orientation (Herman's orientation factor ƒ = 0.922), high strength (419.2 MPa), and high modulus (26.2 GPa), respectively, which are 1.06, 5.57, and 3.49 times higher compared to GO films prepared through the frequently used doctor blade method. The good orientation of GO is remained and further improved to the ultra-high orientation (ƒ = 0.968) after being graphitized at 3150 °C and roll pressing, and the oriented thick graphene films achieved the highest thermal conductivity (1629 W m−1 K−1 for 86 μm and 1593 W m−1 K−1 for 110 μm) compared to other graphene films mentioned in the literature as having a similar thickness. The multi-layered shearing strategy represents a facile technology for assembling two-dimensional (2D) nanoscale building blocks into a macroscopic structure with good orientation and high performance.

Effect of phase evolution and pyroplastic formation behavior on glass-ceramic foam derived from silicomanganese slag and feldspar tailings

Utilizing solid waste to produce foam material has become a significant direction in resource recycling. This study focuses solely on using silicomanganese slag and feldspar tailings as raw materials, utilizing a powder sintering process to produce autocatalytic foaming glass–ceramic foam. We formulated four mix ratios based on the compositional characteristics of the silicomanganese slag and feldspar tailings. The study then explored the evolution of phase formation and macroscopic pore morphology under varying preparation temperatures. Moreover, through multi-phase co-melting experiments, this work unveiled the high-temperature molten mass generation mechanism between silicomanganese slag and feldspar tailings. Our findings reveal that the glass melt generated from silicomanganese slag particles and the 'solid–liquid erosion behavior' of feldspar particles play pivotal roles in the formation of high-temperature co-melt substances. As the sintering temperature increases, the mixed powder exhibits three different states of high-temperature molten mass, which are the reasons for the evolution of the macroscopic pore structure. It is suggested that the addition of silicomanganese slag should be less than 50 %, and the heat treatment temperature should be below 1145 °C in preparing glass–ceramic foam with silicomanganese slag and feldspar tailings. The sample with 40 % silicomanganese slag and 60 % feldspar tailings, treated at 1140 °C, yielded glass–ceramic foam with a compressive strength of 1.68 MPa, apparent density of 0.279 g/cm3, porosity of 81.7 %, and thermal conductivity of 0.074 W·m−1·K−1. In summary, this study provides a novel approach for the high-value utilization of silicomanganese slag and offers an economical route for developing lightweight, eco-friendly structural materials.

Study on design strategies and on new structure-performance relationships for CO2 capture in gas-liquid hollow fiber membrane contactors

The urgent need for carbon dioxide (CO2) capture technologies motivates this chemical engineering study, which systematically investigates the influence of macroscopic and microscopic structure on the CO2 absorption performance of hydrophobic alumina (Al2O3) hollow fiber membrane (A-HFMs) contactors. Six different A-HFMs prepared using the non-solvent-induced phase separation (NIPS) method with select solvents followed by sintering at 1300°C were then tested for chemical CO2 absorption in an A-HFM contactor using a monoethanolamine (MEA) solution. The hydrophobicity of the coatings applied on the A-HFM surfaces was confirmed by the water contact angle and thermogravimetric (TGA) analysis. Pearson's statistical analysis of a correlation matrix revealed the strength of relationships between nine variables, including outer diameter (mm), inner diameter (mm), percentage of sponge layer (%), pore size (nm), maximum pore size (nm), mechanical strength (MPa), surface porosity (m−1), overall porosity (%), and CO2 absorption flux (mol m−2 s−1). Building upon these findings, this study unveils a novel non-linear function linking three specific microscopic characteristics— pore size, surface porosity, and a geometric sponge layer factor—to CO2 absorption flux, offering valuable insights for optimizing hydrophobic A-HFM design and enhancing CO2 capture efficiency. The A-HFM, characterized by the combination of three factors (higher pore size, increased surface porosity, and a thicker sponge layer), achieved a CO2 absorption flux of 6.36 ×10−3 mol m−2 s−1 at room temperature, showcasing its exceptional performance in capturing CO2. The resulting empirical morphological factor provides a novel approach for enhancing the performance of CO2 absorption through A-HFM design optimization.

Effective C4 Separation by Zeolite Metal-Organic Framework Composite Membranes.

Inorganic zeolites have excellent molecular sieving properties, but they are difficult to process into macroscopic structures. In this work, we use metal-organic framework (MOF) glass as substrates to engineer the interface with inorganic zeolites, and then assemble the discrete crystalline zeolite powders into monolithic structures. The zeolites are well dispersed and stabilized within the MOF glass matrix, and the monolith has satisfactory mechanical stabilities for membrane applications. We demonstrate the effective separation performance of the membrane for 1,3-butadiene (C4H6) from other C4 hydrocarbons, which is a crucial and challenging separation in the chemical industry. The membrane achieves a high permeance of C4H6 (693.00±21.83 GPU) and a high selectivity over n-butene, n-butane, isobutene, and isobutane (9.72, 9.94, 10.31, and 11.94, respectively). This strategy opens up new possibilities for developing advanced membrane materials for difficult hydrocarbon separations.

Effective C4 Separation by Zeolite Metal–Organic Framework Composite Membranes

AbstractInorganic zeolites have excellent molecular sieving properties, but they are difficult to process into macroscopic structures. In this work, we use metal–organic framework (MOF) glass as substrates to engineer the interface with inorganic zeolites, and then assemble the discrete crystalline zeolite powders into monolithic structures. The zeolites are well dispersed and stabilized within the MOF glass matrix, and the monolith has satisfactory mechanical stabilities for membrane applications. We demonstrate the effective separation performance of the membrane for 1,3‐butadiene (C4H6) from other C4 hydrocarbons, which is a crucial and challenging separation in the chemical industry. The membrane achieves a high permeance of C4H6 (693.00±21.83 GPU) and a high selectivity over n‐butene, n‐butane, isobutene, and isobutane (9.72, 9.94, 10.31, and 11.94, respectively). This strategy opens up new possibilities for developing advanced membrane materials for difficult hydrocarbon separations.