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Recent studies have revealed that the integration of metal nanoparticles (NPs) with photocatalysts allows the metal NPs to serve as cocatalysts, significantly enhancing reactant efficiency near nanostructures through the surface plasmon resonance (SPR) effect. On this basis, we synthesized highly reactive FePt quantum dots (FePt QDs) with tailored configurations, manipulating the Pt coordination environment and combining FePt QDs with ultrathin two-dimensional nickel metal-organic layer (Ni-MOL) nanosheets. X-ray absorption fine spectroscopy (XAFS) confirmed the distinctive Pt-Fe configuration after photoactivation. The optimized loading amount of FePt QDs led to a hydrogen evolution reaction (HER) yield of 113 mmol·g -1 ·h -1 after activation, with the catalyst remaining stable over five cycles. The improved reaction efficiency stemmed from Pt coordination adjustments and a localized SPR effect, supported by ultraviolet-visible (UV-vis), infrared (IR), Raman, and XAFS characterizations. A comparative analysis was conducted with Ni-MOL deposited with platinum NPs, further underscoring the distinct advantages of FePt QDs and corroborating by density functional theory (DFT) calculations, which revealed favorable d-band center properties. These findings offer a promising avenue for the development of highly efficient and stable nanoalloy photocatalysts.

Lithium-sulfur (Li-S) technology stands out as a promising energy storage system. However, its journey toward practical implementation is hindered by sluggish sulfur reduction reaction (SRR) kinetics. A free-standing graphene aerogel (GA) combined with a copper-based metal-organic framework (MOF-GA) is fabricated as the sulfur host material for Li-S battery cathodes. The presence of MOF particles assumes a dual role, demonstrating its efficacy not only as a catalyst for the reduction reaction of graphene oxide (GO) but also as an electrochemical catalyst to promote sluggish SRR kinetics. The former amplifies electron transfer kinetics within the electrode, and the latter elevates the overall cell performance. Experimental results and theoretical calculations have proven the catalytic activity of MOF-GA electrodes, leading to a higher sulfur utilization of over 80% and a lower capacity decay of 0.082% per cycle. Under extreme conditions, the Li-S cells show a high initial specific capacity of 1113.0 mAh·g -1 under an elevated loading of 4.25 mg·cm -2 and a high sulfur fraction >70%. This study shows the effectiveness of the synergist effects of MOF particles within the GA framework in promoting the sulfur redox reaction in Li-S batteries.

Neonicotinoid insecticides (NNIs) are extensively utilized globally because of their efficient and broad-spectrum properties. However, their residues are also extensively distributed in the environment. Herein, MIL-101-SO 3 Na with abundant -NH- and sulfonate groups was synthesized via chloromethylation and nucleophilic substitution postmodification strategies and used to extract NNIs via solid-phase extraction. MIL-101-SO 3 Na was enhanced by introducing C-H···N hydrogen bonds to strengthen interaction forces and -SO 3 Na groups to adjust surface charge and enhance electrostatic attraction. This modification and the substantial specific surface area (998 m 2 ·g -1 ) of the metal-organic framework markedly enhanced the enrichment efficiency of MIL-101. The proposed method based on MIL-101-SO 3 Na exhibited a minimal detection threshold (0.04-0.87 ng·L -1 ), an extensive linear spectrum (1-2000 ng·L -1 ), and notable accuracy (a variation of 3.02-11.8%) in water and drink samples. NNI concentrations between 0.25 and 24.2 ng·L -1 in fruit juice and tea samples were accurately identified using the proposed method, demonstrating its feasibility in practical applications. The postmodification of MIL-101-SO 3 Na is an exceptional and promising approach for the sensitive detection of ultratrace NNI levels in complex matrices.

Optimizing the balance between thermodynamic interaction and kinetic diffusion is pivotal to obtaining high-performance gas chromatographic stationary phases. Here, three aluminum-based metal-organic frameworks featuring fym topology were chosen to achieve such balance by refined controlling the thermodynamic interactions toward analytes at angstrom level in a confined space. The CAU-10-H with the middle-sized channels (5.4 Å) provided weak interactions with xylenes because of the benzene ring around the channel, leading to the fastest diffusion. While the MIL-160 provided stronger interactions toward the analytes due to the abundance of O-heterocyclic sites of 2,5-furandicarboxylic acid ligands, resulting in slightly higher diffusion barriers. Thereby, although MIL-160 had a larger channel (5.9 Å) than CAU-10-H, the xylenes still diffused more slowly in MIL-160 than in CAU-10-H. The CAU-10-NH 2 with the channel of 4.7 Å provided overstrong thermodynamic interactions and significant stereospecific blockade to the analytes because of the NH 2 sites in the confined channels. These factors collectively contributed to achieving the lowest diffusion kinetics. The confined interactions were also proved by molecular dynamics simulation. Furthermore, the application indicated that MIL-160 exhibited the highest separation ability as a GC stationary phase among all reported materials. This strategy offers an approach for developing high-performance MOF stationary phases.

Zirconium-based metal-organic frameworks (MOFs) have become one of the most promising materials for the adsorption and destruction of chemical warfare agents. While numerous studies have shown differences in reactivity based on MOF topology and postsynthetic modification, the understanding of how modifying MOF macromorphology is less understood. MOF xerogels demonstrate modified defect levels and larger porosity, which increase the number of and access to potential active sites. Indeed, UiO-66 and NU-901 xerogels display reaction rates 2 and 3 times higher, respectively, for the hydrolysis of DMNP relative to their powder morphologies. Upon recycling, MOF-808 xerogel outperforms MOF-808 powder, previously noted as the fastest Zr 6 MOF for hydrolysis of organophosphate nerve agents. The increase in reactivity is largely driven by a higher external surface area and the introduction of mesoporosity to previously microporous materials.

Chemisorption on organometallic-based adsorbents is crucial for the controlled separation and purification of targeted systems. Herein, oriented 1D NH 2 -CuBDC·H 2 O metal-organic frameworks (MOFs) featuring accessible Cu II sites are successfully fabricated by bottom-up interfacial polymerization. The prepared MOFs, as deliberately self-assembled secondary particles, exhibit a visually detectable coordination-responsive characteristic induced by the nucleophilic substitution and competitive coordination of guest molecules. As a versatile phase-change chemosorbent, the MOFs exhibit unprecedented NH 3 capture (18.83 mmol g -1 at 298 K) and bioethanol dehydration performance (enriching ethanol from 99% to 99.99% within 10 min by direct adsorption separation of liquid mixtures of ethanol and water). Furthermore, the raw materials for preparing the 1D MOFs are inexpensive and readily available, and the facile regeneration with water washing at room temperature effectively minimizes the energy consumption and cost of recycling, enabling it to be the most valuable adsorbent for the removal and separation of target substances.

Ionogel-based piezoionic sensors feel motions and strains like human skin relying on reversible ion migrations under external mechanical stimulus and are of great importance to artificial intelligence. However, conventional ion-conductive polymers behave with degraded electrical and mechanical properties after thousands of strain cycles, and the discarded materials and devices become electronic wastes as well. Here, we develop ultrastretchable ionogels with superior electrical properties via the mediation of metal-organic frameworks, whose properties are attributed to reversible molecule interactions inside the material system. Ionogels present excellent mechanical properties with breaking elongation as high as 850%, exceeding most previously reported similar materials, and the high conductivity enables further application in sensor devices. In addition, our ionogels display superior recyclability because of the reversible physical and chemical interactions inside material molecules, which are eco-friendly to the environment. As a result, the ionogel-based piezoionic sensors deliver high sensitivity, flexibility, cyclic stability, and signal reliability, which are of great significance to wearable applications in human-motion detections such as throat vibration, facial expression, joint mobility, and finger movement. Our study paves the way for ultrastretchable and eco-friendly ionogel design for flexible electrochemical devices.

Hydrophilic metal-organic frameworks (MOFs) are promising for solar steam generation from waste or seawater. In this study, we propose a MOF-based Janus membrane for efficient solar steam generation. We selected MOF-303 for its hydrophilic properties and 1D channels with 6.5 Å cavity diameter, making it an excellent water-absorbing layer. Characterization via Raman spectroscopy and differential scanning calorimetry indicates that the nanoconfinement within MOF-303 can reduce the water evaporation enthalpy, thereby boosting water production efficiency. When deposited on various substrates, MOF-303 aimed to optimize solar steam generation. We enhanced the membrane performance by incorporating carbon black (CB), polydopamine (PDA), and perfluoro-functionalized poly(3,4-ethylenedioxythiophene) (PEDOT-F), materials known for their solar-to-thermal energy conversion capabilities. PEDOT-F, in particular, also served as a hydrophobic layer, preventing salt recrystallization during seawater operation. Under one sun irradiation, the water evaporation flux for deionized water increased from 0.31 to 0.79 kg h -1 m -2 using a porous hydrophilic poly(vinylidene difluoride) substrate and further to 2.36 kg h -1 m -2 with the optimized MOF-303-CB/PDA-PEDOT-F membrane, achieving an energy conversion efficiency of 97%. Additionally, the desalination capability of the MOF-303 membrane effectively reduced metal ion concentrations (Na + , K + , Mg 2+ , and Ca 2+ ) to meet the WHO drinking water standards. These findings demonstrate the significant potential of the MOF-303-based Janus membrane for practical applications in solar steam generation and desalination, combining high water evaporation rates with excellent energy conversion efficiency.

The extensive use of insecticides, such as pyrethroids, and pharmaceutical drugs, such as doxorubicin (DOX) has significantly increased to meet the growing demand for food production and disease treatment. Among them, 3-phenoxybenzoic acid (3-PBA), a metabolite of pyrethroid insecticides, poses various health and environmental risks. Similarly, DOX is a well-known anticancer drug and has been continuously used for many years. The high demand and unregulated disposal of these substances raise concerns for both humans and the environment. To address this issue, there is a pressing need to monitor the presence of these analytes in wastewater to protect our ecosystems. This challenge has inspired us to develop an MOF-based fluorometric dual sensor capable of rapid and selective detection of these analytes in aqueous solutions. This work represents the first MOF-based dual probe for detecting these targeted analytes. There was a 98% fluorescence quenching upon the introduction of DOX whereas about a 11-fold increment of the probe's fluorescence intensity took place in the presence of 3-PBA. The sensitivity of the probe is notably high as limits of detection (LOD) are 8.7 nM for DOX and 1.2 nM for 3-PBA. Our designed probe has the highest K SV value for DOX which is 3.37 × 10 6 M -1 . The MOF demonstrated remarkable rapid response time of just 5 and 10 s for DOX and 3-PBA, respectively. The MOF exhibited outstanding selectivity in detecting DOX and 3-PBA, even when other interfering substances were present. We tested the probe's sensing abilities in various environments, such as serum, urine, wastewater, and different pH levels. These findings underscore the sensor's practicality and usefulness in real-world applications. The underlying mechanisms driving the sensing processes were thoroughly investigated by using various modern analytical methods.

Ischemic osteonecrosis, particularly glucocorticoid-induced osteonecrosis of the femoral head (GIONFH), is primarily due to the dysfunction of osteogenesis and angiogenesis. miRNA, as a therapeutic system with immense potential, plays a vital role in the treatment of various diseases. However, due to the unique microenvironmental structure of bone tissue, especially in the case of GIONFH, where there is a deficiency in the vascular system, it is challenging to effectively target and deliver to the ischemic osteonecrosis area. A drug delivery system assisted by genetically engineered cell membranes holds promise in addressing the challenge of targeted miRNA delivery. Herein, we leverage the potential of miR-21 in modulating osteogenesis and angiogenesis to design an innovative biomimetic nanoplatform system. First, we employed metal-organic frameworks (MOFs) as the core structure to load miR-21-m (miR-21-m@MOF). The nanoparticles were further coated with the membrane of bone marrow mesenchymal stem cells overexpressing CXCR4 (CM-miR-21-m@MOF), enhancing their ability to target ischemic bone areas via the CXCR4-SDF1 axis. These biomimetic nanocomposites possess both bone-targeting and ischemia-guiding capabilities, actively targeting GIONFH lesions to release miR-21-m into target cells, thereby silencing PTEN gene and activating the PI3K-AKT signaling pathway to regulate osteogenesis and angiogenesis. This innovative miRNA delivery system provides a promising therapeutic avenue for GIONFH and potentially other related ischemic bone diseases. STATEMENT OF SIGNIFICANCE., Competing Interests: Declaration competing of interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

A complex air pollution environment requires filters to be multifunctional. Nanofibrous materials with surface-loaded metal–organic frameworks (MOF-fibers) are reasonable structures for multifunctional air filtration. These materials can not only utilize the network structure of fibers to intercept particulate matter (PM) but also retain the porous structure of the MOFs to adsorb toxic gas. Epitaxial growth methods are commonly utilized to prepare MOF-fibers but are uneconomical and time-consuming. Herein, a facile self-assembly strategy is developed to prepare zeolitic imidazolate framework-polyimide (ZIF-PI) nanofibers with an interconnected network structure and high porosity for air filtration applications. Due to their unique structure, the ZIF-PI nanofibrous membrane exhibited high PM2.5 filtration efficiency and enhanced SO2 adsorption capacity. Moreover, by exploring the morphology evolution of the ZIF-PI nanofibrous membrane, a possible "synergistic effect of hydrophobic and electrostatic force" self-assembly mechanism was demonstrated. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are considered potential materials in the gas sensor field because of their extremely porous, adjustable characteristics and high surface area. In this paper, based on a ZIF-8 precursor, ZnO-CuO hollow nanocage heterostructure materials were successfully fabricated by a multistep method, and the prepared ZnO-CuO sensor exhibited excellent respond to H2S. We found that when the mass ratio of CuO reaches 1 wt %, the response to 10 ppm hydrogen sulfide (H2S) was as high as 70, and the recovery time was 55 s at a low temperature of 115 °C. Such a ZnO-CuO sensor has a highly selective response to H2S gas. In addition, the lower detection limit can reach 200 ppb. Furthermore, the gas sensors also had high consistency and repeatability. Gas sensing mechanism studies have shown that the special nanocage structure with larger specific surface area helps to increase gas adsorption and diffusion on the surface of sensing materials, and the formation of p–n heterostructures by the introduction of CuO improves the sensitive and selective response to H2S. This work will improve the practical application of H2S gas sensors for their simple preparation method and research into the response mechanism. [ABSTRACT FROM AUTHOR]

The C–C coupling is an efficient route toward the synthesis of symmetric biphenyls from aryl halides. Herein, a cost-effective visible nanophotocatalyst system (Cu3P/hBN), consisting of heterogeneous, nanoporous, and nanosized Cu3P (derived from HKUST MOF) and hexagonal boron nitride (hBN), is employed for the photocatalytic coupling of aryl halides. The catalyst efficiently executes the aryl halide coupling to biphenyls under visible light and in the presence of air at room temperature. The electron/hole pairs can be readily generated upon visible light excitation of the Cu3P nanophotocatalyst, but the low band gap of Cu3P promotes the fast recombination of generated electrons/holes, thereby rendering Cu3P inefficient for photocatalysis. However, the association of a small amount of hBN, which is a structural analogue of graphene and carbon nitride, with Cu3P to form the Cu3P/hBN composite promotes the separation of electrons as hBN can provide its surface to the excited electrons of Cu3P, making them active to act on surface-adsorbed active reactant molecules, whereas the holes remain confined to the valence band of Cu3P. Cu3P is a P-type semiconductor that provides Cu (+1) active sites that change to Cu (+2) during the photocatalytic cycle. The oxidized active sites consisting of Cu (+2) promote further enhancement of electrostatic interactions between the catalyst and the attached aromatic halide molecules. The excited electrons generated in the catalyst upon light exposure act on oxygen molecules to further lead to superoxide radical anion (O2–•) radical formation. The formed O2–• radicals then act on activated halide molecules and convert them to biphenyls. [ABSTRACT FROM AUTHOR]

Supercapacitors have received much attention to meet the growing demand for energy storage devices with high power and energy densities. Despite the efforts, it is still a long way to bridge the gap in the energy densities between batteries and capacitors. In this work, we introduce a hybrid framework for synergetic effects of heteromaterials to improve the performance of supercapacitors. Our composite electrode consists of carbon nanotubes (CNTs) with high conductivity, zeolitic imidazole framework (ZIF) allowing a fast ion diffusion, and molybdenum disulfide (MoS2) bearing a large ion capacity. The hybrid electrode demonstrates exceptional performances, with a specific capacitance over 262 F/g and an energy density of ∼52.4 Wh/kg at a scan rate of 20 mV/s while keeping a high power density (∼3680 W/kg at a scan rate of 100 mV/s). The kinetics analysis reveals that the multicomponent electrode behaves as a hybrid supercapacitor storing energy by not only fast capacitive but also faradaic reactive processes. The CNT-ZIF-MoS2 electrode demonstrates remarkable durability with an outstanding capacitance retention over 10 000 charge/discharge cycles. This work should be beneficial in designing hybrid materials for high-performance supercapacitor devices with an ultralong life span. [ABSTRACT FROM AUTHOR]

Due to their very high porosity and superior textural properties, metal–organic frameworks (MOFs) are promising nanoporous materials for hydrogen storage by cryocompression. Herein, we investigated hydrogen adsorption on four commercial MOFs, namely, MIL53-Al, MOF-5, HKUST-1, and MOF-177, over a temperature range of 77 to 273 K and pressures up to 14 MPa. The modified Dubinin–Astakhov equation was used to fit the experimental adsorption data, and six parameters (m, nmax, α, β, P0, and Va) were obtained. We concluded that the parameters nmax and Va are related to the micropore volume, while α, β, m, and P0 are related to the average micropore size. Compared to hydrogen compression in an empty tank, the introduction of MOF-5 enhanced the volumetric hydrogen storage at 77 K and 10 MPa from 31 to 42 kg m–3. The released H2 capacities of MOFs from a loading pressure of 10 MPa to a discharge pressure of 0.5 MPa were determined for either isothermal discharge at 77 K or after temperature increase to 160 K. For MOF-5, the amount of usable hydrogen increased up to 10.6 wt % (40.8 mg cm–3) by pressure drop (from 10 to 0.5 MPa) and temperature increase (from 77 to 160 K). [ABSTRACT FROM AUTHOR]

The earlier described organic coordination polymer [Zn3(HCit)2(H2O)2]n (HCit is citric acid) (I) formed completely by the biocompatible components is synthesized under hydrothermal conditions. The selection of the hydrothermal synthesis conditions makes it possible to obtain the polymer as high-quality single crystals and perform a detailed analysis of the electron density distribution function recovered using the data of a high-resolution X-ray diffraction experiment. This study is the second example of such investigations for the biocompatible metal−organic framework. [ABSTRACT FROM AUTHOR]

We report a versatile strategy based on the use of multifunctional mussel-inspired polydopamine for constructing well-defined single-nanoparticle@metal-organic framework (MOF) core-shell nanohybrids. The capability of polydopamine to form a robust conformal coating on colloidal substrates of any composition and to direct the heterogeneous nucleation and growth of MOFs makes it possible for customized structural integration of a broad range of inorganic/organic nanoparticles and functional MOFs. Furthermore, the unique redox activity of polydopamine adds additional possibilities to tailor the functionalities of the nanohybrids by sandwiching plasmonic/catalytic metal nanostructures between the core and shell via localized reduction. The core-shell nanohybrids, with the molecular sieving effect of the MOF shell complementing the intrinsic properties of nanoparticle cores, represent a unique class of nanomaterials of considerable current interest for catalysis, sensing, and nanomedicine.

Efficient water splitting is limited by the sluggish oxygen evolution reaction (OER) to a large extent, which inhibits the development of sustainable energy and has attracted widespread attention. In this work, a type of microsized Cu-based metal–organic framework (MOF) of Cu-BTB has been successfully synthesized by a rapid reaction within half an hour. During the subsequent pyrolysis, a large number of N-containing carbon nanotubes (NCNTs) are grown on the entire surface of hierarchically porous MOF-derived nanosized carbons through the introduction of ethylene and ammonia, denoted as NCNT/Cu/C. After oxidation, NCNT-supported nanosized copper oxide embedded in a carbon matrix (NCNT/CuO/C) is finally obtained to show the preserved morphology and high graphitization degree. The high specific surface area and conductivity of NCNTs for NCNT/CuO/C further enable the electrolyte to make better contact with the active materials during the OER. Finally, the optimal nanosized NCNT/CuO/C exhibits a high degree of improvement in OER performance, in which it attains an overpotential of only 369 mV at 10 mA cm–2, and its Tafel slope is calculated to be 87.4 mV dec–1, indicating fast reaction kinetics. The demonstrated work proves that the method of doping NCNTs with nanosized copper oxides can effectively enhance the efficacy of water oxidation, which can be further used in future energy applications. [ABSTRACT FROM AUTHOR]

In order to improve room-temperature hydrogen storage, platinum (Pt) nanoparticles (NPs) are doped onto the Zr-terephthalate metal–organic framework (MOF) UiO-66 and its derivatives for H2 adsorption via spillover effect under a high-pressure environment. Different MOF synthetic modulators are applied for MOF nanoparticle size manipulation, and surface functionality is designed to improve Pt dispersion. Powder X-ray diffraction shows retained MOF integrity after Pt decoration, and the broad Pt peak indicates well-dispersed Pt NPs. The MOF high specific surface areas are slightly reduced after Pt doping with the retained micropore size in the nanometer scale. The hydrogen storage capacity can be improved from 0.08 to 0.71 wt % at 300 K and 30 bar. It is suggested by X-ray photoelectron spectroscopy that the hydrogen capacity enhancement is due to H2 spillover in which spiltover hydrogen radicals hydrogenate carboxylates in MOF supports. Although Pt aggregation reduces H2 capacity in cycles, it is found that MOF and Pt nanoparticle sizes are critical for H2 spillover for subsequent room-temperature hydrogen storage. [ABSTRACT FROM AUTHOR]

Cd(II) complex 1 , namely {[Cd(HL)]·CH 3 OH} n was design as a new fluorescence probe for measuring concentration of Cu2+ ion in aqueous solution. Complex 1 is a 3,6-connected double-layered porous metal–organic framework, which was synthesized by optimizing the ratio of Cd(OH) 2 and a new ligand 4'-(((1-carboxyethyl)amino)methyl)-[1,1′-biphenyl]-3,5-dicarboxylic acid (H 3 L) under solvothermal conditions. It not only had good thermal and solvent stabilities, but also displayed a strong solid-state fluorescence centered at 375 nm with a moderate quantum yield of 37.12% under excitation at 275 nm. More importantly, its fluorescence could be obviously quenched by the addition of Cu2+ ion. The fluorescence quenching may be caused by the weak coordination interaction between Cu2+ and the uncoordinated imino N in ligand (HL)2–, as well as the slightly competitive absorption of excitation light by Cu2+. In the low concentration range of Cu2+ ion, the fluorescence quenching efficiency of complex 1 is closely related to the concentration of Cu2+ ion, and the relationship between fluorescence quenching efficiency and the concentration of added Cu2+ ion could be well fitted by Stern-Volmer equation with K SV being 1.589 × 104 M−1 and the detection limit for Cu2+ ion being 5.7 μM. Our case may provide potential applications for the detection of Cu2+ ion in daily domestic water. A new double-layered porous metal‒organic framework prepared by the solvothermal reaction of an amino acid-functionalized aromatic tricarboxylic acid ligand and Cd(OH) 2 displays good thermal stability, solvent stability, and strong fluorescence emission, and can be used as a highly sensitive water-stable fluorescence probe for detecting Cu2+. [Display omitted] • Amino acid-functionalized aromatic tricarboxylic acid ligand. • Double-layered metal-organic framework based on binuclear subunit [Cd 2 (COO) 4 ]. • Water-stable fluorescence probe of Cu(II). [ABSTRACT FROM AUTHOR]

Copper ion (Cu2+) detection remains an important task for monitoring water quality because of its specific toxicity. Herein, a new dual-signal fluorescent probe was developed by combining zeolitic imidazolate framework-8 (ZIF-8) and lanthanide for the detection of Cu2+ for the first time. The lanthanide coordination polymer (guanosine monophosphate and Eu3+, GMP/Eu) was initially incorporated into ZIF-8 to yield ZIF-8/GMP/Eu nanomaterials with extremely weak single emission fluorescence at 618 nm. It was found that the resulted nanomaterials could display a dual emission fluorescence at 515 nm and 618 nm after the introduction of tetracycline (TC) due to the synergistic effect of aggregation-induced emission effect (AIE, TC induced by ZIF-8) and antenna effect (AE, between TC and GMP/Eu). Interestingly, in the presence of Cu2+, the AIE of TC was destroyed because of the interaction of Cu2+ with ZIF-8 and TC. The AE between TC and GMP/Eu disappeared due to the formation of complex between TC and Cu2+. A dual-signal fluorescent probe of ZIF-8/GMP/Eu/TC was thereby established for sensing Cu2+ in the range of 0.5–100 μM. Such a dual-signal response strategy that intelligently utilized the "ON"/"OFF" of AIE and AE can not only eliminate the background interference, but also ensure the improved selectivity of Cu2+ sensing. Subsequently, the dual-signal fluorimetric strategy was applied for the detection of Cu2+ in environmental water samples, indicating the potential feasibility of applications for water quality monitoring. [Display omitted] • A dual-signal fluorescent probe was developed by combining ZIF-8, GMP/Eu and TC for detection of Cu2+ for the first time. • The coordination polymers fluorescent probe combined the unique property of the ZIF-8, GMP/Eu and TC. • The synergistic effect of AIE and AE enable the probe with unique dual-signal response ability to Cu2+. • The dual-signal strategy utilized the AIE and AE eliminated the interference and ensured the selectivity of Cu2+ sensing. [ABSTRACT FROM AUTHOR]

As a new type of multifunctional material, metal−organic frameworks (MOFs) have a wide application prospect in the field of chiral separation. In this study, a homochiral MOF [Ni(S-mal)(bpy)]n was synthesized by the reaction of S-malic acid (S-mal) and 4,4′-bipyridine (bpy) with nickel acetate. The homochiral MOF [Ni(S-mal)(bpy)]n was explored as a new chiral stationary phase for HPLC separation of racemic compounds using n-hexane−isopropanol as a mobile phase. A series of racemic compounds were separated on this column. The results showed that the homochiral MOF column exhibited good chiral recognition ability toward six racemic compounds including amlodipine, ibuprofen, flurbiprofen, propranolol hydrochloride, chlorphenamine maleate and 1-p-chlorobenzyl−ethanol. The homochiral MOF column also offered good reproducibility and stability for the enantioseparation. [ABSTRACT FROM AUTHOR]

Hydrogen is the most convenient recourse to shift from fossil fuels to an efficient and sustainable source of energy in automobiles. Achieving a high hydrogen weight percentage while storing hydrogen is the prime challenge in using hydrogen fuel. In the current study, a nanoporous metal–organic framework of 2.069 nm pore size having R-graphyne as a linker (GR–MOF) is reported for the first time. Employing density functional theory, the hydrogen sorption characteristics of GR–MOF functionalized with Li and its mechanism are investigated. A Kubas-like mechanism is observed in the process of hydrogen adsorption with sorption energies in the 0.25–0.27 eV range, with the highest hydrogen weight percentage of 11.95%. It is observed during the van 't Hoff desorption and Born–Oppenheimer molecular dynamics study that GR–MOF reversibly stores hydrogen under operable thermodynamic conditions (100–300 K, 1–3 atm). GR–MOF stands out to be a prospective material for reversible hydrogen storage under the norms set by the Department of Energy, USA. [ABSTRACT FROM AUTHOR]

It is a significant challenge to prepare highly active and high-cobalt (Co) loading Fischer–Tropsch synthesis (FTS) catalysts for syngas conversion. Herein, a metal–organic framework named ZIF-67 was grown in situ on a CoAl layered-double-hydroxide (LDH) to obtain hierarchical LDH/ZIF-67 structures. Highly dispersed cobalt (Co)-embedded porous nanoplatelet (CoPNP) catalysts suitable for FTS were prepared by subsequent pyrolysis. High Co loading (over 50 wt % Co) was realized in CoPNP with suitable particle sizes and active Co dispersion. Remarkably, CoPNP showed a hierarchical architecture with a high specific surface area, and the porous channels could enhance syngas diffusion and hydrocarbon production, boosting the CO conversion and C5+ selectivity. Consequently, CoPNP revealed extraordinarily high activity in FTS with maximum 71.6% CO conversion and 70.2% C5+ long-chain hydrocarbon selectivity. The work reveals a methodology for the design and preparation of FTS catalysts with boosted performance and affords a promising pathway to design other FTS catalysts. [ABSTRACT FROM AUTHOR]

The present paper reports the preparation of zirconium-based metal–organic framework (Zr-MOF) nanocomposites, which were fabricated on the surface of a reduced graphene oxide (rGO) sheet via an in situ method. The Zr-MOF/rGO-nanocatalyst is successfully synthesized and tested for 2,3-dihydroquinazolin-4-(1H)-one derivative with isolated yields (89–97%) within 30 min. We have also synthesized a total of 14 aromatic derivatives of 2,3-dihydroquinazolin-4-(1H)-one compound and evaluated the possible binding of these compounds to the calf-thymus DNA (CT-DNA). Furthermore, binding with CT-DNA is examined by the fluorescence spectroscopic technique and molecular docking studies. Fluorescence studies show G12, G13, and G14 compounds and give the best results amongst all synthesized 2,3-dihydroquinazolin-4-(1H)-one derivatives. Allosteric inhibition of CT-DNA is performed and evaluated by molecular docking studies based on minimum binding energy, which corresponds to the fluorescence results. These comparative results proved G12, G13, and G14 compounds bind more effectively as compared to 3,8-diamino-5-ethyl-6-phenylphenanthridinium bromide. The characterization of the Zr-MOF/rGO-nanocatalyst is elucidated through Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy, thermogravimetric analysis, field emission scanning electron microscopy, high-resolution transmission electron microscopy Raman spectrum, inductively coupled plasma optical emission spectroscopy, and nuclear magnetic resonance spectroscopy. The present nanocatalyst is readily recycled, reused five times, and found to be stable, with stability confirmed through FTIR spectroscopy and PXRD. [ABSTRACT FROM AUTHOR]

Self-assembly of an environmentally friendly non-lanthanide barium-based metal–organic framework {[Ba-(2,6-ndc)-(H2O)2]·H2O} (1, 2,6-ndc = 2,6-naphthalenedicarboxylate) (Ba-MOF) is reported. The complex displays an intrinsic broad-band white light emission with a Commission International de I'Eclairage (CIE) index of (0.32, 0.33), and a corresponding yield of about 75%, when excited at a wavelength of 374 nm. The continuous broad band can be attributed to the inherent nature of Ba-MOF (1), i.e., interligand (π–π*) and ligand–metal charge transfer mechanisms, resulting in a white light emission. Moreover, a device is fabricated using a nanometer-scale thin film of Ba-MOF (1) as an active material and the resulting device exhibits a white electroluminescence spectrum. In comparison with the traditional two-component light-emitting diodes (LEDs), this MOF-based white light LED system has significant advantages such as its ability to function as a phosphor-free, single-component broad-band emitter, high stability, low cost, and minimal environmental footprints. Density functional theory (DFT) calculations are carried out to better comprehend the origin of this white light emission from 1. This Ba-MOF-based white light emitter has the potential for being an environmentally friendly and low-cost source for white light solid-state applications. [ABSTRACT FROM AUTHOR]

Transition metal-nitrogen-carbon complexes, featuring single metal atoms embedded in a nitrogen-doped carbon matrix, emerge as promising alternatives to traditional platinum-based catalysts, offering cost-effectiveness, abundance, and enhanced catalytic performance. This work introduces a novel method for the etching and doping of zeolitic imidazolate frameworks (ZIFs) with transition metals, creating a uniform distribution of secondary metal centers on ZIF surfaces. By disrupting the crystalline symmetry of ZIFs through synthetic defect engineering, we gain access to their entire internal volume, creating multichannel pathways. The absorption of metal ions is theoretically simulated, demonstrating their thermodynamically spontaneous nature. The selective removal of defect channels under Lewis acidic conditions, induced by metal ion alcoholysis/hydrolysis, facilitates the introduction of metal atoms into ZIF cavities. The resulting single-atom catalyst, after pyrolysis, features a three-dimensional (3D) multichannel structure, high surface area, and uniformly dispersed metal atoms within the N-doped carbon matrix, establishing it as an exceptional catalyst for the oxygen reduction reaction (ORR). Our findings highlight the potential of using metal etching in defect-engineered metal-organic frameworks (MOFs) for single-atom catalyst preparation, paving the way for the next generation of high-performance, cost-effective ORR catalysts in sustainable energy systems.

The abuse and excessive discharge of organic pollutants such as nitroaromatic compounds (NACs) have become a hot topic of concern for all humanity and society, and the development of fast, effective, and targeted technical means for detecting NACs also faces many challenges. Here, we reported a strontium-based metal-organic framework (MOF) {[Sr 2 (tcbpe)(H 2 O) 4 ]} n ( Sr-tcbpe ), in which tcbpe represents deprotonated 4',4‴,4″‴,4‴‴-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1'biphenyl]-4-carboxylic acid)). In Sr-tcbpe , Sr-O polyhedron and deprotonated tcbpe 4- ligand have a staggered connection to form a self-assembled three-dimensional network structure. In addition, it is found that Sr-tcbpe undergoes no luminescent color change when grinding under solvent protection, while mechanochromic fluorescence behavior is observed when grinding directly, leading to luminescent color changes from cyan to green ( Sr-tcbpe-G ). Additionally, Sr-tcbpe and Sr-tcbpe-G could selectively detect PNP, DNP, and TNP, and Sr-tcbpe achieves visual fluorescence sensing detection toward TNP at a limit of detection as low as 2.25 μM. Moreover, during the detection process, unexpectedly, TNP exhibits a selective etching effect on Sr-tcbpe , which could drill nano holes with different sizes on the surface area of MOF materials to a certain extent, achieving the conversion of chemical energy to mechanical energy. In addition, the successful preparation of a portable sensor Sr-tcbpe @gypsum block provides a platform for the perfect combination of mechanochromic fluorescence behavior and visualization detection toward TNP. It lays the foundation for the practical application of MOF materials in daily life.

Morphological engineering is crucial for conceiving high-efficiency electromagnetic wave (EMW) absorption materials. However, for carbon fiber-based composites, the management of micromorphology is significantly astricted by complex fabrication. It remains highly challenging to clarify the micromorphological influences on the EMW loss mechanism of carbon fiber-based absorption materials. In this work, micromorphology-optimized Cu/C nanocomposite fibers are prepared by virtue of a metal-organic framework (MOF) template-assisted strategy. Through skillfully grafting the morphology-regulation capacity of MOFs onto composite fibers, the Oswald maturation and particle distribution issues of Cu nanoparticles are settled, and the efficient electron transport pathways are established by the bead-like structure of the fiber matrix. Compared to prepared conventional Cu/C nanocomposite fibers, the MOF template-assisted strategy stimulates a remarkable leap in EMW absorption performance. The minimum reflection loss value of Cu/C-40 can reach -64.5 dB, 15.96 times lower than that of a conventional sample (Cu/C-2). The maximum effective absorption bandwidth extends to 6.08 GHz, contrasting the ineffective performance of Cu/C-2. Systematic research demonstrates that the enabled graphite-catalytic function of Cu nanoparticles collaborated with an optimized conductive network structure plays a pivotal role in creating field-induced leakage currents, facilitating conductive loss, the primary contributor to EMW dissipation. This work establishes a correlation mechanism between micromorphology and EMW loss, presenting a compelling example of customizable carbon fiber-based absorbers.

An outstanding challenge for the field of metal-organic frameworks (MOFs) is structuring to form forms with greater useability. Reactive extrusion printing (REP) is a technique for the direct formation of films from their molecular components on-demand and on-location. Here we apply REP for the first time to zeolitic imidazolate frameworks (ZIFs) and study the interplay of solvent and molarity ratio on the phase distribution between ZIF-8 and ZIF-L in reactive printed films. Our results show that REP controllably directs phase formation between ZIF-L and ZIF-8 and that REP also gives control over crystal size and that high-quality ZIF-8 films, in particular, are produced in low-dispersity interconnected nanoparticulate form. Importantly, we show that REP is responsive to established surface-functionalization techniques to control important printing parameters of line width and thickness. This work expands the repertoire of REP to the important class of ZIFs.

Aqueous rechargeable Zn batteries (AZBs) are considered to be promising next-generation battery systems. However, the growth of Zn dendrites and water-induced side reactions have hindered their practical application, especially with regard to long-term cyclability. To address these challenges, we introduce a supramolecular metal-organic framework (SMOF) coating layer using an α-cyclodextrin-based MOF (α-CD-MOF-K) and a polymeric binder. The plate-like α-CD-MOF-K particles, combined with the polymeric binder create dense and homogeneous Zn 2+ ion conductive pore channels that can vertically transport Zn 2+ ions through the cavity while restricting the contact of water molecules. Molecular dynamics (MD) simulation verifies that Zn 2+ ions can reversibly migrate through the pores of α-CD-MOF-K by partial dehydration. The uniform Zn deposition/dissolution promotes a smooth solid-electrolyte interface layer on the Zn metal anode and effectively suppresses side reactions with free water molecules. The α-CD-MOF-K@Zn symmetric cell exhibits stable cycling and a small polarization voltage of 70 mV for 800 h at 5 mA cm -2 , and the α-CD-MOF-K@Zn|α-MnO 2 full cell shows only 0.12% capacity decay per cycle at a rate of 1 A g -1 .

Promotion of oxygen reduction reaction (ORR) kinetics, to a large extent, depends on the rational modulation of the electronic structure and mass diffusion of electrocatalysts. Herein, a ferrocene (Fc)-assisted strategy is developed to prepare Fc-trapped ZnMo-hybrid zeolitic imidazolate framework (Fc@ZnMo-HZIF-50) and the derived Fe single atom coupling with MoC nanoparticles, coembedded in hierarchically porous N-doped carbon cubes (MoC@FeNC-50). The introduced Fc is utilized not only as an iron source for single atoms but also as a morphology regulator for generating a hierarchically porous structure. The redistribution of electrons between Fe single atoms and MoC nanoparticles effectively promotes the adsorption of O 2 and the formation of *OOH intermediates during the ORR process. Along with a 3D hierarchically porous architecture for enhanced mass transport, the as-fabricated MoC@FeNC-50 presents excellent activity ( E 1/2 = 0.83 V) and durability (only 9.5% decay in current after 40000 s). This work could inspire valuable insights into the construction of efficient electrocatalysts through electron configuration and kinetics engineering.

Mass transfer of bulky molecules, e.g ., bioenzymes, particularly for cross-scale multibiomolecules, imposes serious challenges for microporous metal-organic frameworks (MOFs). Here, we create a hierarchically porous MOF heterostructure featuring highly region-ordered micro-, meso-, and macro-pores by growing a microporous ZIF-8 shell onto a hollow Prussian blue core through an epitaxial growth strategy. This allows for localized loading of large bioenzyme glucose oxidase (GOx) and small drug 5-fluorouracil (5-FU) within specific pores simultaneously and triggers unique guest-carrier cooperative anticancer capabilities. The stable ZIF-8 outer layer effectively blocks the core pores, preventing the undesired leakage of GOx into normal tissues. The acidity-induced ZIF-8 degradation gradually releases Zn 2+ and loaded 5-FU for chemotherapy under acidic tumor microenvironments. With the loss of the shielding effect of the ZIF-8 coating, the released GOx depletes intratumoral glucose (Glu) for starvation therapy. Notably, an accelerated cascade reaction occurs between ZIF-8 decomposition and GOx release, facilitated by the modulator factor of Glu. This culminates in the realization of synergistic cancer therapy, as comprehensively demonstrated by in vitro and in vivo experiments, as well as transcriptome sequencing analyses. Our work not only introduces a hierarchically porous MOF heterostructure with highly region-ordered pores but also provides a perspective for guest-carrier cooperative anticancer therapy.

The complex microenvironment of diabetic wounds often hinders the healing process, ultimately leading to the formation of diabetic foot ulcers and even death. Dual monitoring and treatment of wounds can significantly reduce the incidence of such cases. Herein, a multifunctional Janus membrane (3D chitosan sponge-ZE/polycaprolactone nanofibers-ZP) was developed by incorporating the zinc metal-organic framework, europium metal-organic framework, and phenol red into nanofibers for diabetic wound monitoring and treatment. The directional water transport capacity of the resulting Janus membrane allows for unidirectional and irreversible drainage of wound exudate, and the multifunctional Janus membrane creates up to a 99% antibacterial environment, both of which can treat wounds. Moreover, the pH (5-8) and H 2 O 2 (0.00-0.80 μM) levels of the wound can be monitored using the color-changing property of phenol red and the fluorescence characteristic of Eu-MOF on the obtained membrane, respectively. The healing stages of the wound can also be monitored by analyzing the RGB values of the targeted membrane images. This design can more accurately reflect the wound state and treat the wound to reduce bacterial infection and accelerate wound healing, which has been demonstrated in in vivo experiments. The results provide an important basis for early intervention in diabetic patients.

Sodium-metal batteries, heralded for high energy density and cost-effectiveness, are compromised by an unstable solid electrolyte interphase (SEI) and dendrite formation, which hinder practical applications. Herein, a zirconium-based metal-organic framework nanostructure coating (ZMOF-NSC) was constructed in a low-loss, flexible manner. Comprehensive studies show that ZMOF-NSC, with its periodically ordered nanochannels and organized pore structures, enhances ion transport and decreases the Na + migration energy barrier, thus ensuring uniform ion flux and achieving uniform spherical deposition. Additionally, ZMOF-NSC facilitates partial desolvation, catalyzing the formation of an inorganic-rich, dual-layered SEI that effectively protects the anode and suppresses dendrite formation. Consequently, the ZMOF-NSC@Na symmetric battery exhibits an impressive lifespan of over 2500 h, demonstrating extended operational longevity. The Na 3 V 2 (PO 4 ) 3 ∥ZMOF-NSC@Na batteries demonstrate exceptional cycling stability with 81% capacity retention after 2000 cycles at 10 C, maintaining stability over 3000 cycles at 20 C. Moreover, the NVP∥ZMOF-NSC@Na battery achieves an energy density of 370 Wh kg -1 and a power density of 10,484 W kg -1 , indicating superior durability and performance. This significant finding highlights the significant potential of structured MOFs to induce a dual-layered SEI, advancing the commercialization of durable, dendrite-free sodium metal batteries. The precise design of self-assembled pore structures and surface active sites in MOFs demonstrates significant potential in advancing the commercialization of durable, dendrite-free electrodes of metal-based rechargeable batteries.

The stimulus-responsive regulation of enzyme catalytic activity and selectivity provides a new opportunity to extend the functionality and efficiency of immobilized enzymes. This work aims to design and synthesize a thermo-switchable enzyme@MOF for size-selective biocatalysis and biosensing through the immobilization of Candida rugosa lipase (CRL) within ZIF-8 functionalized with thermally responsive polymer, poly( N -isopropylacrylamide) (PNIPAM) (CRL@ZIF-8-PNIPAM). Unlike free CRL, which does not demonstrate substrate selectivity, we can reversibly tune the pore size of the ZIF-8-PNIPAM nanostructures (open pores or blocked pores) through temperature stimulus and subsequently modulate the substrate selectivity of CRL@ZIF-8-PNIPAM. CRL@ZIF-8-PNIPAM had the highest hydrolytic activity for small molecules (12 mM p -nitrophenol/mg protein/min, 4-nitrophenyl butyrate ( p -NP Be)) and the lowest hydrolytic activity for large molecules (0.16 mM p-nitrophenol/mg protein/min, 4-nitrophenyl palmitate ( p -NP P)). In addition, CRL@ZIF-8-PNIPAM demonstrated thermo-switchable behavior for large molecules ( p -NP P). The p -NP P hydrolytic activity of CRL@ZIF-8-PNIPAM was significantly lower at 40 °C (blocked pores) than at 27 °C (open pores). However, the transition of blocked pores and open pores is a gradual process that resulted in a delay in the "thermo-switchable" catalytic behavior of CRL@ZIF-8-PNIPAM during thermal cycling. CRL@ZIF-8-PNIPAM was also successfully used for the fabrication of electrochemical biosensors for the selective biosensing of pesticides with different molecular sizes.

Metal-organic frameworks (MOFs) are a promising class of porous materials for the design of gas sensing arrays, which are often called electronic noses. Due to their chemical and structural tunability, MOFs are a highly diverse class of materials that align well with the similarly diverse class of volatile organic compounds (VOCs) of interest in many gas detection applications. In principle, by choosing the right combination of cross-sensitive MOFs, layered on appropriate signal transducers, one can design an array that yields detailed information about the composition of a complex gas mixture. However, despite the vast number of MOFs from which one can choose, gas sensing arrays that rely too heavily on distinct chemistries can be impractical from the cost and complexity perspective. On the other hand, it is difficult for small arrays to have the desired selectivity and sensitivity for challenging sensing applications, such as detecting weakly adsorbing gases with weak signals, or conversely, strongly adsorbing gases that readily saturate MOF pores. In this work, we employed gas adsorption simulations to explore the use of a variable pressure sensing array as a means of improving both sensitivity and selectivity as well as increasing the information content provided by each array. We studied nine different MOFs (HKUST-1, IRMOF-1, MgMOF-74, MOF-177, MOF-801, NU-100, NU-125, UiO-66, and ZIF-8) and four different gas mixtures, each containing nitrogen, oxygen, carbon dioxide, and exactly one of the hydrogen, methane, hydrogen sulfide, or benzene. We found that by lowering the pressure, we can limit the saturation of MOFs, and by raising the pressure, we can concentrate weakly adsorbing gases, in both cases, improving gas detection with the resulting arrays. In many cases, changing the system pressure yielded a better improvement in performance (as measured by the Kullback-Liebler divergence of gas composition probability distributions) than including additional MOFs. We thus demonstrated and quantified how sensing at multiple pressures can increase information content and cross-sensitivity in MOF-based arrays while limiting the number of unique materials needed in the device.

Capacitive storage devices allow for fast charge and discharge cycles, making them the perfect complements to batteries for high power applications. Many materials display interesting capacitive properties when they are put in contact with ionic solutions despite their very different structures and (surface) reactivity. Among them, nanocarbons are the most important for practical applications, but many nanomaterials have recently emerged, such as conductive metal-organic frameworks, 2D materials, and a wide variety of metal oxides. These heterogeneous and complex electrode materials are difficult to model with conventional approaches. However, the development of computational methods, the incorporation of machine learning techniques, and the increasing power in high performance computing now allow us to tackle these types of systems. In this Review, we summarize the current efforts in this direction. We show that depending on the nature of the materials and of the charging mechanisms, different methods, or combinations of them, can provide desirable atomic-scale insight on the interactions at play. We mainly focus on two important aspects: (i) the study of ion adsorption in complex nanoporous materials, which require the extension of constant potential molecular dynamics to multicomponent systems, and (ii) the characterization of Faradaic processes in pseudocapacitors, that involves the use of electronic structure-based methods. We also discuss how recently developed simulation methods will allow bridges to be made between double-layer capacitors and pseudocapacitors for future high power electricity storage devices.

Timely blood reperfusion after myocardial infarction (MI) paradoxically triggers ischemia-reperfusion injury (I/RI), which currently has not been conquered by clinical treatments. Among innovative repair strategies for myocardial I/RI, microRNAs (miRNAs) are expected as genetic tools to rescue damaged myocardium. Our previous study identified that miR-30d can provide protection against myocardial apoptosis and fibrosis to alleviate myocardial injury. Although common methods such as liposomes and viral vectors have been used for miRNA transfection, their therapeutic efficiencies have struggled with inefficient in vivo delivery, susceptible inactivation, and immunogenicity. Here, we establish a nanoparticle-patch system for miR-30d delivery in a murine myocardial I/RI model, which contains ZIF-8 nanoparticles and a conductive microneedle patch. Loaded with miR-30d, ZIF-8 nanoparticles leveraging the proton sponge effect enable miR-30d to escape the endocytic pathway, thus avoiding premature degradation in lysosomes. Meanwhile, the conductive microneedle patch offers a distinct advantage by intramyocardial administration for localized, effective, and sustained miR-30d delivery, and it simultaneously releases Au nanoparticles to reconstruct electrical impulses within the infarcted myocardium. Consequently, the nanoparticle-patch system supports the consistent and robust expression of miR-30d in cardiomyocytes. Results from echocardiography and electrocardiogram (ECG) revealed improved heart functions and standard ECG wave patterns in myocardial I/RI mice after implantation of a nanoparticle-patch system for 3 and 6 weeks. In summary, our work incorporated conductive microneedle patch and miR-30d nanodelivery systems to synergistically transcend the limitations of common RNA transfection methods, thus mitigating myocardial I/RI.

Solid-state nanochannels (SSNs) have emerged as promising platforms for controlling ionic transport at the nanoscale. SSNs are highly versatile, and this feature can be enhanced through their combination with porous materials such as Metal-Organic Frameworks (MOF). By selection of specific building blocks and experimental conditions, different MOF architectures can be obtained, and this can influence the ionic transport properties through the nanochannel. Herein, we study the effects of confined synthesis of Zr-based UiO-66 MOF on the ion transport properties of single bullet-shaped poly(ethylene terephthalate) (PET) nanochannels. We have found that emerging textural properties from the MOF phase play a determinant role in controlling ionic transport through the nanochannel. We demonstrate that a transition from ion current saturation regimes to diode-like regimes can be obtained by employing different synthetic approaches, namely, counterdiffusion synthesis, where MOF precursors are kept separate and forced to diffuse through the nanochannel, and one-pot synthesis, where both precursors are placed at both ends of the channel. Also, by considering the dependence of the charge state of the UiO-66 MOF on the protonation degree, pH changes offered a mechanism to tune the iontronic output (and selectivity) among different regimes, including anion-driven rectification, cation-driven rectification, ion current saturation, and ohmic behavior. Furthermore, Poisson-Nernst-Planck (PNP) simulations were employed to rationalize the different iontronic outputs observed experimentally for membranes modified by different methods. Our results demonstrate a straightforward tool to synthesize MOF-based SSN membranes with tunable ion transport regimes.

As a noninvasive treatment modality, high-intensity focused ultrasound (HIFU)-induced antitumor immune responses play a vital role in surgery prognosis. However, limited response intensity largely hinders postoperative immunotherapy. Herein, a hypoxia-specific metal-organic framework (MOF) nanosystem, coordinated by Fe 3+ , hypoxic-activated prodrug AQ4N, and IDO-1 signaling pathway inhibitor NLG919, is developed for the potentiating immunotherapy of HIFU surgery. The loaded AQ4N enhances the photoacoustic imaging effects to achieve accurate intraoperative navigation. Within the HIFU-established severe hypoxic environment, AQ4N is activated sequentially, following which it cooperates with Fe 3+ to effectively provoke immunogenic cell death. In addition, potent NLG919 suppresses IDO-1 activity and degrades the immunosuppressive tumor microenvironment aggravated by postoperative hypoxia. In vivo studies demonstrate that the MOF-mediated immunotherapy greatly inhibits the growth of primary/distant tumors and eliminates lung metastasis. This work establishes a robust delivery platform to improve immunotherapy and the overall prognosis of HIFU surgery with high specificity and potency.

An alarming increase in the use of pesticides and organoarsenic compounds and their toxic impacts on the environment have inspired us to develop a selective and highly sensitive sensor for the detection of these pollutants. Herein, a bio-friendly, low-cost Al-based luminescent metal-organic framework ( 1' )-based fluorescent material is demonstrated that helps in sustaining water quality by rapid monitoring and quantification of a long-established pesticide (pendimethalin) and a widely employed organoarsenic feed additive (roxarsone). A pyridine-functionalized porous aluminum-based metal-organic framework (Al-MOF) was solvothermally synthesized. After activation, it was used for fast (<10 s) and selective turn-off detection of roxarsone and pendimethalin over other competitive analytes. This is the first MOF-based recyclable sensor for pendimethalin with a remarkably low limit of detection (LOD, 14.4 nM). Real-time effectiveness in detection of pendimethalin in various vegetable and food extracts was successfully verified. Moreover, the aqueous-phase recyclable detection of roxarsone with an ultralow detection limit (13.1 nM) makes it a potential candidate for real-time application. The detection limits for roxarsone and pendimethalin are lower than the existing luminescent material based sensors. Furthermore, the detection of roxarsone in different environmental water and a wide pH range with a good recovery percentage was demonstrated. In addition, a cheap and bio-friendly 1'@chitosan@paper strip composite was prepared and successfully employed for the hands-on detection of pendimethalin and roxarsone. The turn-off behavior of 1' in the presence of pendimethalin and roxarsone was examined systematically, and plausible mechanistic pathways were proposed with the help of multiple experimental evidences.

The discovery of cuproptosis, a copper-dependent mechanism of programmed cell death, has provided a way for cancer treatment. However, cuproptosis has inherent limitations, including potential cellular harm, the lack of targeting, and insufficient efficacy as a standalone treatment. Therefore, exogenously controlled combination treatments have emerged as key strategies for cuproptosis-based oncotherapy. In this study, a Cu 2- x Se@cMOF nanoplatform was constructed for combined sonodynamic/cuproptosis/gas therapy. This platform enabled precise cancer cotreatment, with external control allowing the selective induction of cuproptosis in cancer cells. This approach effectively prevented cancer metastasis and recurrence. Furthermore, Cu 2- x Se@cMOF was combined with the antiprogrammed cell death protein ligand-1 antibody (aPD-L1), and this combination maximized the advantages of cuproptosis and immune checkpoint therapy. Additionally, under ultrasound irradiation, the H 2 Se gas generated from Cu 2- x Se@cMOF induced cytotoxicity in cancer cells. Further, it generated reactive oxygen species, which hindered cell survival and proliferation. This study reports an externally controlled system for cuproptosis induction that combines a carbonized metal-organic framework with aPD-L1 to enhance cancer treatment. This precision and reinforced cuproptosis cancer therapy platform could be valuable as an effective therapeutic agent to reduce cancer mortality and morbidity in the future.

We demonstrate a simple droplet diagnostic approach to monitor the UiO-66 MOF (metal-organic framework) synthesis and its quality using the sessile droplet drying phenomenon. Drying a sessile droplet involves evaporation-driven hydrodynamic flow and particle-nature-dependent self-assembled deposition. In general, the MOF synthesis process involves different sizes and physicochemical nature of particles in every synthesis stage. Equivalent quantities of each of purified pore-activated UiO-66 MOF, yet-to-be-purified pore-inactivated UiO-66 MOF, and reaction precursors of UiO-66 MOF give different deposition patterns when a well-dispersed aqueous droplet of these materials undergoes drying over substrates of varying stiffness and wettability. Yet-to-be-purified, pore-inactivated UiO-66 MOF nanoparticles undergo transport toward the droplet periphery, leading to a thick ring-like deposition at the dried droplet edge. Under appropriate drying conditions, such a deposit leads to desiccation-type mud-like reticular cracking. We study the origin of such ring-like deposits and cracks to understand how the surface charge density of UiO-66 particles controls their stability. We demonstrate that ZrOCl 2 salt trapped in a nonpurified pore-inactivated UiO-66 MOF moiety is the principal reason for ring-like deposit formation and subsequent cracking in its dried aqueous droplet edge. Qualitatively, we identified Lewis acid salts that are capable of acting as Bro̷nsted acid upon hydrolysis (like FeCl 3 , SnCl 2 , and ZrOCl 2 ), influence surface charge density and colloidal stability of dispersed UiO-66 MOF particles. As a result, immediate particle coagulation is avoided, so those travel to the droplet edge, forming ring-like deposition and subsequent cracking upon drying. Further, we show that crack patterns on such deposits are highly dependent on the stiffness and temperature of depositing substrates via a competition between axial and lateral strains at the deposit-substrate interface.

Mixed matrix membranes represent an important technology for gas separations. Nanosheets of metal-organic framework (MOF) materials of high aspect ratio and size-selective gas transport properties have the potential to promote the efficient mixing of components to form membranes for gas separation. Herein, we report a bottom-up synthesis of extended sheets of kagomé (kgm) topology, kgm t -Bu , via the linkage of [Cu 2 (O 2 CR) 4 ] paddlewheels with 5- tert -butylisophthalic acid. The growth of the layered structure can be controlled by the choice of solvent and modulator. Nanosheets of kgm t -Bu of average thickness of 20 nm and aspect ratio of 40 to 50 can be obtained, and the sieving effect of the channels in kgm t -Bu boost the efficient separation of CO 2 over CH 4 . A mixed matrix membrane comprising kgm t -Bu nanosheets with Matrimid shows a 32% enhancement in CO 2 /CH 4 selectivity compared with the membrane incorporating the MOF in the particulate form.

Combining halide perovskite quantum dots (QDs) and metal-organic frameworks (MOFs) material is challenging when the QDs' size is larger than the MOFs' nanopores. Here, we adopted a simple defect engineering approach to increase the size of zeolitic imidazolate framework 90 (ZIF-90)'s pores size to better load CH 3 NH 3 PbBr 3 perovskite QDs. This defect structure effect can be easily achieved by adjusting the metal-to-ligand ratio throughout the ZIF-90 synthesis process. The QDs are then grown in the defective structure, resulting in a hybrid ZIF-90-perovskite (ZP) composite. The QDs in ZP composites occupied the gap of 10-18 nm defective ZIF-90 crystal and interestingly isolated the QDs with high stability in aqueous solution. We also investigated the relationship between defect engineering and fluorescence sensing, finding that the aqueous Cu 2+ ion concentration was directly correlated to defective ZIF-90 and ZP composites. We also found that the role of the O-Cu coordination bonds and CH 3 NHCu + species formation in the materials when they reacted with Cu 2+ was responsible for this relationship. Finally, this strategy was successful in developing Cu 2+ ion fluorescence sensing in water with better selectivity and sensitivity.

Targeted drug delivery systems based on metal-organic frameworks (MOFs) have progressed tremendously since inception and are now widely applicable in diverse scientific fields. However, translating MOF agents directly to targeted drug delivery systems remains a challenge due to the biomolecular corona phenomenon. Here, we observed that supramolecular conjugation of antibodies to the surface of MOF particles (MOF-808) via electrostatic interactions and coordination bonding can reduce protein adhesion in biological environments and show stealth shields. Once antibodies are stably conjugated to particles, they were neither easily exchanged with nor covered by biomolecule proteins, which is indicative of the stealth effect. Moreover, upon conjugation of the MOF particle with specific targeted antibodies, namely, anti-CD44, human epidermal growth factor receptor 2 (HER2), and epidermal growth factor receptor (EGFR), the resulting hybrid exhibits an augmented targeting efficacy toward cancer cells overexpressing these receptors, such as HeLa, SK-BR-3, and 4T1, as evidenced by flow cytometry. The therapeutic effectiveness of the antibody-conjugated MOF (anti-M808) was further evaluated through in vivo imaging and the assessment of tumor inhibition effects using IR-780-loaded EGFR-M808 in a 4T1 tumor xenograft model employing nude mice. This study therefore provides insight into the use of supramolecular antibody conjugation as a promising method for developing MOF-based drug delivery systems.

Polyoxometalates (POMs) are discrete anionic clusters whose rich redox properties, strong Bro̷nsted acidity, and high availability of active sites make them potent catalysts for oxidation reactions. Metal-organic frameworks (MOFs) have emerged as tunable, porous platforms to immobilize POMs, thus increasing their solution stability and catalytic activity. While POM@MOF composite materials have been widely used for a variety of applications, little is known about the thermodynamics of the encapsulation process. Here, we utilize an up-and-coming technique in the field of heterogeneous materials, isothermal titration calorimetry (ITC), to obtain full thermodynamic profiles (Δ H , Δ S , Δ G , and K a ) of POM binding. Six different 8-connected hexanuclear Zr-MOFs were investigated to determine the impact of MOF topology ( csq , scu , and the ) on POM encapsulation thermodynamics.

For mass spectrometry (MS)-based phosphoproteomics studies, sample pretreatment is an essential step for efficient identification of low-abundance phosphopeptides. Herein, a cobalt phthalocyanine-modified magnetic metal-organic framework (MOF) (Fe 3 O 4 @MIL-101-CoPc) was prepared and applied to enrich phosphopeptides before MS analysis. Fe 3 O 4 @MIL-101-CoPc exhibited an excellent magnetic response (74.98 emu g -1 ) and good hydrophilicity (7.75°), which were favorable for the enrichment. Fe 3 O 4 @MIL-101-CoPc showed good enrichment performance with high selectivity (1:1:5000), sensitivity (0.1 fmol), reusability (10 circles), and recovery (91.3%). Additionally, the Fe 3 O 4 @MIL-101-CoPc-based MS method was able to successfully detect 827 phosphopeptides from the A549 cell lysate, demonstrating a high enrichment efficiency (89.3%). This study promotes the application of postfunctionalized MOFs for phosphoproteomics analysis.