Publications by authors named "Taehyun Bae"

The development of high-performance membranes selective for carbon dioxide is critically important for advancing energy-efficient carbon dioxide capture technologies. Although molecular sieves have long been attractive membrane materials, turning them into practical membrane applications has been challenging. Here, we introduce an innovative approach for crafting a polymeric molecular sieve membrane to achieve outstanding carbon dioxide separation performance while upholding the mechanical stability.

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Strategic design of nanostructures, such as the core-shell configuration, offers a promising avenue to harness the desired properties while mitigating the inherent limitations of individual materials. In our pursuit of synergizing the advantages of two distinct porous materials, namely, zeolites and metal-organic frameworks (MOFs), we aimed to develop the zeolite@MOF core-shell structures. To synthesize this targeted material while minimizing undesirable side reactions, we devised an innovative approach involving ion-exchange-induced crystallization and post-synthetic conversion.

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Property optimization through orientation control of metal-organic framework (MOF) crystals that exhibit anisotropic crystal structures continues to garner tremendous interest. Herein, an electric field is utilized to post-synthetically control the orientation of conductive layered Cu(HHTP) (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) crystals dispersed in an electronically insulating poly(ethylene glycol) diacrylate (PEGDA) oligomer matrix. Optical and electrical measurements are performed to investigate the impact of the electric field on the alignment of Cu(HHTP) crystals and the formation of aggregated microstructures, which leads to an ≈5000-fold increase in the conductivity of the composite.

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Metal-organic frameworks (MOFs) represent crystalline materials constructed from combinations of metal and organic units to often yield anisotropic porous structures and physical properties. Postsynthetic methods to align the MOF crystals in bulk remain scarce yet tremendously important to fully utilize their structure-driven intrinsic properties. Herein, we present an unprecedented composite of liquid crystals (LCs) and MOFs and demonstrate the use of nematic LCs to dynamically control the orientation of MOF crystals with exceptional order parameters (as high as 0.

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Graphene oxide (GO), a carbonaceous 2D nanomaterial, has received significant interest as a next-generation membrane building block. To fabricate high-performance membranes, an effective strategy involves stacking GO nanosheets in laminated structures, thereby creating unique nanochannel galleries. One outstanding merit of laminar GO membranes is that their permselectivity is readily tunable by tailoring the size of the nanochannels.

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Light hydrocarbons, obtained through the petroleum refining process, are used in numerous applications. The separation of the various light hydrocarbons is challenging and expensive due to their similar melting and boiling points. Alternative methods have been investigated to supplement cryogenic distillation, which is energy intensive.

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In this study, a novel polybenzimidazole (PBI)-based organic solvent nanofiltration (OSN) membrane possessing excellent stability under high pH condition was developed. To improve the chemical stability, the pristine PBI membrane was crosslinked with a silane precursor containing an epoxy end group. In detail, hydrolysis and condensation reaction of methoxysilane in the 3-glycidyloxypropyl trimethoxysilane (GPTMS) yields organic-inorganic networks within the PBI membrane structure.

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This Special Issue, entitled "Emerging Materials for Mixed-Matrix Membranes" was introduced to cover the recent progress in the development of materials for mixed-matrix membranes (MMMs) with potential application in fields such as sea water desalination, gas separation, pharmaceutical separation, wastewater treatment and the removal of pathogenic (viruses and bacteria) microorganisms as well as solvents and resource recovery [...

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The use of Prussian blue analogues (PBA) materials in electrochemical energy storage and harvesting has gained much interest, necessitating the further clarification of their electrochemical characteristics. However, there is no well-defined technique for manufacturing PBA-based microelectrochemical devices because the PBA film deposition method has not been well studied. In this study, we developed the following deposition method for growing copper hexacyanoferrate (CuHCFe) thin film: copper thin film is immersed into a potassium hexacyanoferrate solution, following which the redox reaction induces the spontaneous deposition of CuHCFe thin film on the copper thin film.

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Three different zeolite nanocrystals (SAPO-34, PS-MFI and ETS-10) were incorporated into the polymer matrix (Matrimid 5218) as polymer precursors, with the aim of fabricating mixed-matrix carbon molecular sieve membranes (CMSMs). These membranes are investigated for their potential for air separation process. Based on our gas permeation results, incorporating porous materials is feasible to improve O permeability, owing to the creation of additional porosities in the resulting mixed-matrix CMSMs.

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To improve the CO/N separation performance, mixed-matrix carbon molecular sieve membranes (mixed-matrix CMSMs) were fabricated and tested. Two carbon-based fillers, graphene oxide (GO) and activated carbon (YP-50F), were separately incorporated into two polymer precursors (Matrimid 5218 and ODPA-TMPDA), and the resulting CMSMs demonstrated improved CO permeability. The improvement afforded by YP-50F was more substantial due to its higher accessible surface area.

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Batteries for contact lenses fabricated by conventional methods could cause severe damage to the eyes if broken. Herein, we present flexible aqueous batteries that operate in tears and provide a safe power supply to smart contact lenses. Nanocomposite flexible electrodes of carbon nanotubes and Prussian blue analogue nanoparticles for cathode and anode were embedded in UV-polymerized hydrogel as not only a soft contact lens but also an ion-permeable separator.

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Hydrogen (H) is an industrial gas that has showcased its importance in several well-known processes such as ammonia, methanol and steel productions, as well as in petrochemical industries. Besides, there is a growing interest in H production and purification owing to the global efforts to minimize the emission of greenhouse gases. Nevertheless, H which is produced synthetically is expected to contain other impurities and unreacted substituents (e.

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Ethnopharmacological Relevance: The dried root of Paeonia lactiflora Pall. (Radix Paeoniae) has been traditionally used to treat various inflammatory diseases in many Asian countries.

Aim Of The Study: Cisplatin is a broad-spectrum anticancer drug used in diverse types of cancer.

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Nanocrystalline UiO-66 and its derivatives (containing -NH, -Br, -(OH)) were developed via pre-synthetic functionalization and incorporated into a polyimide membrane to develop a mixed-matrix membrane (MMM) for CO/N separation. Incorporation of the non-functionalized UiO-66 nanocrystals into the polyimide membrane successfully improved CO permeability, with a slight decrease in CO/N selectivity, owing to its large accessible surface area. The addition of other functional groups further improved the CO/N selectivity of the polymeric membrane, with UiO-66-NH, UiO-66-Br, and UiO-66-(OH) demonstrating improvements of 12%, 4%, and 17%, respectively.

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Membranes for organic solvent nanofiltration (OSN) or solvent-resistant nanofiltration (SRNF) offer unprecedented opportunities for highly efficient and cost-competitive solvent recovery in the pharmaceutical industry. Here, we describe small-flake graphene oxide (SFGO) membranes for high-performance OSN applications. Our strategy exploits lateral dimension control to engineer shorter and less tortuous transport pathways for solvent molecules.

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MXenes are emerging rapidly as a new family of multifunctional nanomaterials with prospective applications rivaling that of graphenes. Herein, a timely account of the design and performance evaluation of MXene-based membranes is provided. First, the preparation and physicochemical characteristics of MXenes are outlined, with a focus on exfoliation, dispersion stability, and processability, which are crucial factors for membrane fabrication.

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Carbon nanotubes (CNTs) with hydrophobic and atomically smooth inner channels are promising for building ultrahigh-flux nanofluidic platforms for energy harvesting, health monitoring, and water purification. Conventional wisdom is that nanoconfinement effects determine water transport in CNTs. Here, using full-atomistic molecular dynamics simulations, it is shown that water transport behavior in CNTs strongly correlates with the electronic properties of single-walled CNTs (metallic (met) vs semiconducting (s/c)), which is as dominant as the effect of nanoconfinement.

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Membrane-based air separation (O/N) is of great importance owing to its energy efficiency as compared to conventional processes. Currently, dense polymeric membranes serve as the main pillar of industrial processes used for the generation of O- and N-enriched gas. However, conventional polymeric membranes often fail to meet the selectivity needs owing to the similarity in the effective diameters of O and N gases.

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The energy-intensive ethylene/ethane separation process is a key challenge to the petrochemical industry. HKUST-1, a metal-organic framework (MOF) which possesses high accessible surface area and porosity, is utilized in mixed-matrix membrane fabrication to investigate its potential for improving the performance for CH/CH separation. Prior to membrane fabrication and gas permeation analysis, nanocrystal HKUST-1 was first synthesized.

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Ethnopharmacological Relevance: The dried root of Paeonia lactiflora Pall. (Radix Paeoniae) has been traditionally used to treat various inflammatory diseases in many Asian countries.

Aim Of The Study: Cancer cachexia is a catabolic syndrome driven by inflammation and characterised by a loss of skeletal muscle.

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Metal-organic frameworks (MOFs) with coordinatively unsaturated (open) metal sites have been intensively investigated in gas separations because their active sites can selectively interact with targeted molecules such as CO. Although such MOFs have shown to exhibit exceptional CO uptake capacity at equilibrium, the dynamic separation behavior is often not satisfactory to be considered in practical applications. Herein, we report a facile and efficient self-sacrifice template strategy based on the nanoscale Kirkendall effect to form novel Co-MOF-74 hollow nanorods enabling adsorption/desorption of gas molecules in a facilitated manner.

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In this study, we report the anti-inflammatory activity of XAV939, a modulator of the Wnt/β-catenin pathway. WNT/β-catenin pathway and NF-κB signaling pathway were examined in LPS-stimulated human bronchial epithelial cells and effects of XAV939 on these pathways were analyzed. The effect of XAV939 was confirmed in human umbilical vein endothelial cells.

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Biogas is an increasingly attractive renewable resource, envisioned to secure future energy demands and help curb global climate change. To capitalize on this resource, membrane processes and state-of-the-art membranes must efficiently recover methane (CH) from biogas by separating carbon dioxide (CO). Composite (a.

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Two-dimensional (2-D) CuBDC nanosheets (ns-CuBDC) with high-aspect-ratios were deliberately paired with polymers possessing high free volumes to fabricate high performance gas separation membranes. Owing to the molecular sieving effect of the filler, a small ns-CuBDC loading (2-4 wt%) could significantly improve the CO/CH selectivities of membranes, resulting in performances that surpass the upper bound limit for polymer membranes.

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