Metal Organic Framework UiO-66 Research Articles

Spatially controlled multicellular differentiation of stem cells using triple factor-releasing metal–organic framework-coated nanoline arrays

Improved in vitro models are needed for regenerative therapy and drug screening. Here, we report on functionally aligned nanoparticle-trapped nanopattern arrays for spatially controlled, precise mesenchymal stem cell differentiation on a single substrate. The arrays comprise nanohole and nanoline arrays fabricated through interference lithography and selectively capture of UiO-67 metal–organic frameworks on nanoline arrays with a 99.8% efficiency using an optimised asymmetric spin-coating method. The UiO-67 metal–organic frameworks contain three osteogenic differentiation factors for sustained release over four weeks. The combination of differentiation factors and patterned array allows for generation of adipocytes, osteoblasts, and adipocyte–osteoblast mixtures on nanohole arrays, nanoline arrays, and at the nanohole–nanoline interface, respectively, with mature osteoblasts exhibiting higher marker expression and mineralisation. The sustained release patterned array holds potential for constructing advanced therapeutic and disease state in vitro cellular models.

Dispersive solid-phase extraction based on metal–organic framework UiO-66: Applying gamma-valerolactone as a green eluent for effective extraction of pyrethroid insecticides in water and food matrix

Dispersive solid-phase extraction based on metal–organic framework UiO-66: Applying gamma-valerolactone as a green eluent for effective extraction of pyrethroid insecticides in water and food matrix

Development of a New UiO-66 Metal–Organic Framework with Two-Dimensional Nanosheet Structure Under Optimized Conditions for Enhanced Removal of Heavy Metals from Water

Development of a New UiO-66 Metal–Organic Framework with Two-Dimensional Nanosheet Structure Under Optimized Conditions for Enhanced Removal of Heavy Metals from Water

Atomized Neutrophil Membrane-coated MOF Nanoparticles for Direct Delivery of Dexamethasone for Severe Pneumonia.

Dexamethasone has proven life-saving in severe acute respiratory syndrome (SARS) and COVID-19 cases. However, its systemic administration is accompanied by serious side effects. Inhalation delivery of dexamethasone (Dex) faces challenges such as low lung deposition, brief residence in the respiratory tract, and the pulmonary mucus barrier, limiting its clinical use. Neutrophil cell membrane-derived nanovesicles, with their ability to specifically target hyper-activated immune cells and excellent mucus permeability, emerge as a promising carrier for pulmonary inhalation therapy. We designed a novel UiO66 metal-organic framework nanoparticle loaded with Dex and coated with neutrophil cell membranes (UiO66-Dex@NMP) for targeted therapy of severe pneumonia. This was achieved by loading Dex into UiO66 pores and subsequently coating with neutrophil membranes for functionalization. Drug release experiments revealed UiO66-Dex@NMP to exhibit favorable sustained-release properties. Additionally, UiO66-Dex@NMP demonstrated excellent targeting capabilities both in vitro and in vivo. In a mouse model of lipopolysaccharide (LPS)-induced pneumonia, UiO66-Dex@NMP significantly reduced lung inflammation compared to both the control model and Dex administered via inhalation. Histopathological analysis further confirmed UiO66-Dex@NMP's ability to alleviate lung tissue damage. UiO66-Dex@NMP represents a novel and safe inhaled delivery carrier for Dex, offering valuable insights into the clinical management of respiratory diseases, including severe pneumonia.

Facile synthesis of flower-like MoS2 anchored on UiO-66 metal–organic framework for supercapacitor application

Facile synthesis of flower-like MoS2 anchored on UiO-66 metal–organic framework for supercapacitor application

Plasmon-Enhanced CO2 Reduction to Liquid Fuel via Modified UiO-66 Photocatalysts

Metal–organic frameworks (MOFs) have emerged as versatile materials with remarkably high surface areas and tunable properties, attracting significant attention for various applications. In this work, the modification of a UiO-66 MOF with metal nanoparticles (NPs) is investigated for the purpose of enhancing its photocatalytic activity for CO2 reduction to liquid fuels. Several NPs (Au, Cu, Ag, Pd, Pt, and Ni) were loaded into the UiO-66 framework and employed as photocatalysts. The synergistic effects of plasmonic resonance and MOF characteristics were investigated to improve photocatalytic performance. The synthesized materials were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), confirming the successful integration of metal NPs onto the UiO-66 framework. Morphological analysis revealed distinct distributions and sizes of NPs on the UiO-66 surface for different metals. Photocatalytic CO2 reduction experiments demonstrated enhanced activity of plasmonic MOFs, yielding methanol and ethanol. The findings revealed by this study provide valuable insights into tailoring MOFs for improved photocatalytic applications through the incorporation of plasmonic metal nanoparticles.

Catalytic and kinetic isotope effect studies of CO2 reduction on Cu-Metalated UiO-66 Metal-Organic framework

Catalytic and kinetic isotope effect studies of CO2 reduction on Cu-Metalated UiO-66 Metal-Organic framework

Functionalized UiO-66 induces shallow electron traps in heterojunctions with InN for enhanced photocathodic water splitting.

Indium nitride (InN) exhibited significant potential as a photoelectrode material for photoelectrochemical (PEC) water splitting, attributed to its superior light absorption, high electron mobility, and direct bandgap. However, its practical application was constrained by rapid carrier recombination occurring within the bulk and at the surface. To address these limitations, researchers developed InN/UiO-66 heterojunction photoelectrodes, which markedly enhanced PEC water splitting for hydrogen production. Functionalization of the UiO-66 metal-organic framework (MOF) with hydroxyl (-OH) groups optimized the bandgap and improved light absorption, facilitating efficient charge separation and transfer processes. The functionalization also mitigated surface defect states in the InN nanorods (NRs), which were a major source of photogenerated carrier recombination, thereby enhancing overall photocatalytic activity. Compared to pristine InN NRs, the optimized InN/UiO-66-(OH)2 electrode achieved a photocurrent density of -0.42mAcm-2 and an applied bias photon-to-current efficiency (ABPE) of 0.47% at -0.5V vs. reversible hydrogen electrode (RHE). Furthermore, the InN/Ag/UiO-66-(OH)2 system demonstrated a hydrogen production rate of 1.82μmolmin-1 under AM 1.5G illumination, with excellent long-term stability. This study provided critical insights into the design of efficient and durable PEC photoelectrodes, achieved the highest hydrogen yield reported for indium-based photocathodes to date, and underscored the promise of InN-based materials for solar-driven hydrogen production in the context of clean energy applications.

Hafnium-Based Metal-Organic Framework Nanosystems Entrapping Squaraines for Efficient NIR-Responsive Photodynamic Therapy.

In this study, we present for the first time the incorporation of two distinct nonsymmetrical squaraines (SQ) into hierarchically porous Hafnium-based UiO-66 Metal-Organic Frameworks (MOFs), each functionalized with various moieties, for application as photosensitizers in photodynamic therapy. SQs are meticulously designed to feature COOH moieties for interaction with the MOF's metallic cluster and bromine atoms to enhance intersystem crossing and reactive oxygen species (ROS) production. The distinct central functionalizations, one with squaric acid and the other with a dicyanovinyl-substituted squaric acid derivative, result in unique geometric conformations. The latter, as well as the molecular size and density, have been analyzed by computational methods, facilitating the optimal design of MOF cavities for SQ accommodation. Our synthetic methodology involves the production of hierarchically porous Hf-MOFs that integrate both micro- and mesopores. The resultant SQ@MOF systems preserve photosensitizing properties, enhancing solubility and stability without compromising ROS generation or MOF structural integrity. As proof of concept, in vitro evaluations against PANC-1 cells were evaluated, demonstrating the cytocompatibility of SQ@MOFs in the dark up to concentrations of 200 μg mL-1. Photoactivity is assessed using a statistical multivariate design, enabling identification of the SQ@MOF system with the highest phototoxicity and determination of the variables that significantly influence phototoxicity.

Defective UIO66 metal-organic framework nanoparticles assisted by cascade isothermal amplification technology for the detection of aflatoxin B1.

Aflatoxin B1 (AFB1) exhibits significant toxicity and pose a serious threat to food safety, environmental hygiene, and public health even in trace amounts. Hence, the development of a rapid, accurate, and sensitive detection technology has become a pivotal aspect of ensuring control standards. In this study, we introduce the UIO66 and two defective dichloroacetic acid@UIO66 (DCA@UIO66, DU) metal-organic framework nanoparticles, named DU1 and DU2, characterized by different defect levels. It is noteworthy that DU1 exhibits superior DNA sensing capability compared to UIO66 and DU2. With a fluorescence quenching efficiency of 92.66% and a recovery efficiency of 1256.75%, DU1 demonstrates the substantial potential in the detection field. Furthermore, we employ cascade isothermal amplification to assist DU1-mediated fluorescence sensors in detecting AFB1. AFB1 is efficiently identified through an aptamer competition process facilitated by magnetic nanoparticles, which initiates the exponential amplification triggered rolling circle amplification reaction, and converts trace amounts of toxin signal into a large number of long single-stranded DNA molecules. Upon recognition of the amplification product by the fluorescent probe on DU1, a more stable double-stranded DNA is formed and leaves the surface of DU1, leading to a significant change in fluorescence intensity. This method exhibits acceptable sensitivity, with a detection limit of 0.09pgmL-1 and a wide detection range spanning from 0.2pgmL-1 to 20pgmL-1. Additionally, this assay exhibits satisfactory specificity and high accuracy in practical sample applications. Our proposed method offers a solid theoretical framework and technical backing, thereby facilitating the establishment of a new generation of mycotoxin detection standards.

Controlling the Mechanism of Nucleation and Growth Enables Synthesis of UiO-66 Metal-Organic Framework with Desired Macroscopic Properties.

By combining in situ X-ray diffraction, Zr K-edge X-ray absorption spectroscopy and 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, we show that the properties of the final MOF are influenced by H2O and HCl via affecting the nucleation and crystal growth at the molecular level. The nucleation implies hydrolysis of monomeric zirconium chloride complexes into zirconium-oxo species, and this process is promoted by H2O and inhibited by HCl, allowing to control crystal size by adjusting H2O/Zr and HCl/Zr ratios. The rate-determining step of crystal growth is represented by the condensation of monomeric and oligomeric zirconium-oxo species into clusters, or nodes, with the structure identical to that in secondary building units (SBU) of UiO-66 framework. The rapid crystallization in the absence of HCl leads to formation of defective secondary building units with missing zirconium atoms, providing a pathway to control the number of defects in UiO-66 crystals. Remarkably, we have shown that assembling of the metal nodes and linkers into the UiO-66 structure is not the rate-limiting step, and the degree of deprotonation of the linker has no direct effect on the crystallization kinetics or crystal size of product.

Enhanced and efficient electrochemical detection of IgG by UiO-66 metal organic framework (MOF) upon 60 MeV N5+ swift ion irradiation

Enhanced and efficient electrochemical detection of IgG by UiO-66 metal organic framework (MOF) upon 60 MeV N5+ swift ion irradiation

UiO-66 MOF/Zr-di-terephthalate/cellulose hybrid composite synthesized via sol-gel approach for the efficient removal of methylene blue dye.

This research addresses the issue of organic dye pollution in water by developing eco-friendly, cost-effective adsorbents. Zr-di-terephthalate organic-inorganic hybrid materials, with and without cellulose, were synthesized using a one-pot sol-gel method with zirconium butoxide and terephthalic acid. The materials were characterized by XRD, FTIR, XPS, SEM, EDS, TEM, and BET analysis and showed a crystalline structure with some amorphous content, high surface area, and small pores, indicative of a composite form containing UiO-66 metal-organic frameworks (MOFs). Adsorption studies on methylene blue dye showed that both materials followed Langmuir isotherms, with maximum adsorption capacities of 147.54mg/g for Zr-(TPA)2-U and 151.38mg/g for Zr-(TPA)2-UC. The materials exhibited rapid adsorption within a short period of 30min and adhered to pseudo-second order kinetics. The adsorption process was spontaneous and endothermic, driven by electrostatic interactions, π-π stacking, pore filling, van der Waals forces, and hydrogen bonding. The fact that the composite materials contain the UiO-66 structure contributed to their effective adsorption by increasing the crystalline properties of the material. The hybrids also showed excellent reusability, maintaining high efficiency over multiple cycles. These findings highlight the potential of Zr-di-terephthalate hybrids as sustainable, high-performance adsorbents for water purification, addressing dye contamination effectively.

UiO-67 metal-organic framework loaded on hardwood biochar for sustainable management of environmental boron contaminations

Boron contamination in water poses significant potential risks to human health and the environment, necessitating the development of efficient, cost-effective, and sustainable remediation technologies. This study introduces a novel composite material combining a zirconium-based metal-organic framework (UiO-67) and a low-cost carbonaceous material (hardwood biochar, BC) with synergetic efficiency to address boron-polluted waters. The UiO-67-biochar (UBC) composite exhibits effective surface chemistry and a remarkably high specific surface area of approximately 881.9m²/g, substantially increasing from the 19.7m²/g of biochar. Our experimental results demonstrate that UBC removed up to 88.5% of boron from 20 ppm polluted water, achieving levels compliant with the WHO standards. The composite also showed excellent reusability, maintaining 95% efficiency over multiple cycles without loss of crystallinity. Life cycle assessment and cost analysis indicate that an optimal MOF to biochar ratio of approximately 60wt% minimises CO2 emissions and costs while maximising the boron removal efficiency. The UiO-67-biochar composites proposed here offers a promising scalable solution for boron contamination and potentially other environmental pollutants, combining the high functionality of UiO-67 with the practical and economic advantages of biochar.

Threading MOF membranes with polymer chains for superior benzene/cyclohexane separation

High performance membranes for benzene/cyclohexane separation are crucial. Metal–organic frameworks (MOFs), given by their high structural designability, are expected to provide satisfying membrane performance for this separation. In this study, polymer chains were threaded into the pores of MOF UiO-66, to reconstruct the structures of the membrane channels. The permeance of benzene and selectivity of benzene/cyclohexane were boosted simultaneously, compared with the bare UiO-66 membranes. The performance enhancement was rationalized since the solubility of benzene was improved meanwhile the diffusivity of cyclohexane dropped by virtue of the new adsorption sites of benzene and narrower membrane channels created by threading polymers. The as-synthesized polyvinyl alcohol (PVA)-threaded UiO-66 membranes exhibited a benzene permeance around 110 GPU and a benzene/cyclohexane selectivity around 30.

Trace Adsorptive Removal of PFAS from Water by Optimizing the UiO-66 MOF Interface.

The confluence of pervasiveness, bioaccumulation, and toxicity in freshwater contaminants presents an environmental threat second to none. Exemplifying this trifecta, per- and polyfluoroalkyl substances (PFAS) present an alarming hazard among the emerging contaminants. State-of-the-art PFAS adsorbents used in drinking water treatment, namely, activated carbons and ion-exchange resins, are handicapped by low adsorption capacity, competitive adsorption, and/or slow kinetics. To overcome these shortcomings, metal-organic frameworks (MOFs) with tailored pore size, surface, and pore chemistry are promising alternatives. Thanks to the compositional modularity of MOFs and polymer-MOF composites, herein we report on a series of water-stable zirconium carboxylate MOFs and their low-cost polymer-grafted composites as C8-PFAS adsorbents with benchmark kinetics and "parts per billion" removal efficiencies. Bespoke insights into the structure-function relationships of PFAS adsorbents are obtained by leveraging interfacial design principles on solid sorbents, creating a synergy between the extrinsic particle surfaces and intrinsic molecular building blocks.

Aliphatic amine-modified recombinant endoskeleton UiO-66 efficiently enhances CO2 capture performance

Rational chemical modification engineering of metal-organic frameworks (MOFs) is an effective means to improve their CO2 capture efficiency. In this study, we prepare UiO-66 MOF impregnated with different types of aliphatic amines using solvothermal and impregnation techniques, respectively, and investigated their performances in CO2 adsorption and CO2/N2 separation using the isothermal adsorption method. Aliphatic amines successfully chemically modifies UiO-66, and their molecules effectively occupied the pores of the UiO-66 framework, which has been confirmed by material characterization, experiments, and DFT-FMO calculations. There are significant improvements in the ability to capture CO2 when aliphatic amines were added to UiO-66 compared to pure UiO-66 (1.39 mmol/g up to 2.11 mmol/g-2.53 mmol/g), attributed to the different types and numbers of amines, and there were also differences in the Zr metal clusters and BDC ligands. Meanwhile, The material has better CO2/N2 adsorption IAST selectivity(98) because its surface area is changed and N2 does not interact specifically with the adsorbent. Furthermore, the CO2 adsorption capacity remains constant across multiple adsorption cycles, highlighting the adsorbent's stability and reliability during repetitive CO2 capture. This study provides new ideas and perspectives for improving the CO2 capture efficiency of UiO-66.

Precision management of Fusarium fujikuroi in rice through seed coating with an enhanced nanopesticide using a tannic acid-ZnII formulation

Seed coating with fungicides is a common practice in controlling seed-borne diseases, but conventional methods often result in high toxicity to plants and soil. In this study, a nanoparticle formulation was successfully developed using the metal–organic framework UiO-66 as a carrier of the fungicide ipconazole (IPC), with a tannic acid (TA)-ZnII coating serving as a protective layer. The IPC@UiO-66-TA-ZnII nanoparticles provided a controlled release, triggered and regulated by environmental factors such as pH and temperature. This formulation efficiently controlled the proliferation of Fusarium fujikuroi spores, with high penetration into both rice roots and fungal mycelia. The product exhibited high antifungal activity, achieving control efficacy rates of 84.09% to 93.10%, low biotoxicity, and promoted rice growth. Compared to the IPC flowable suspension formula, IPC@UiO-66-TA-ZnII improved the physicochemical properties and enzymatic activities in soil. Importantly, it showed potential for mitigating damage to beneficial soil bacteria. This study provides a promising approach for managing plant diseases using nanoscale fungicides in seed treatment.Graphical

Positional Isomerism: A Novel Paradigm for Enhancing Iodine Adsorption in Functionalized Metal-Organic Frameworks.

Porous metal-organic frameworks (MOFs) have shown great potential as adsorbents for capturing radioiodine, a major fission product generated during the reprocessing of nuclear fuel. However, studies exploring the correlation between the structure of MOFs and iodine uptake capacity remain notably rare. In this study, we introduce a new strategy for enhancing the iodine adsorption efficiency of MOFs by strategically varying the position of functional groups on the organic linkers. Employing ligand-functionalized UiO-67 MOFs, our findings reveal that ortho-amino substitution of UiO-67-o-NH2, proximal to the node of the dicarboxylate linker, markedly accelerates adsorption kinetics of iodine vapor in comparison to meta-amino substitution of UiO-67-m-NH2, where the amino groups are oriented away from the node. In contrast, UiO-67-m-NH2 exhibits a higher adsorption capacity of 2.19 g/g, compared to 1.91 g/g for UiO-67-o-NH2, attributable to its higher porosity. Furthermore, a competitive I2/H2O vapor adsorption study demonstrated that UiO-67-o-NH2 exhibits faster adsorption kinetics and higher selectivity for iodine in the presence of water vapor compared to UiO-67-m-NH2. Additionally, the crucial influence of positional isomerism on enhancing iodine adsorption has been corroborated through Raman spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculations. These analyses reveal that the nitrogen atom positioned at the ortho site demonstrates a stronger affinity for iodine molecules compared to the nitrogen atom at the meta site, thereby improving adsorption kinetics.

A new theory, Nanoscale Confinement Polarization Pinning effect for enhancing piezoelectricity of PVDF-HFP, to fabricate piezoelectric sensor for exercise assistance

In this study, a novel theory called Nanoscale Confinement Polarization Pinning (NCPP) theory is proposed. This theory provides theoretical support for the application of heterojunctions composed of porous metal–organic frameworks (MOFs) and conductors or semiconductors in enhancing the piezoelectric effect of piezoelectric polymers. The heterojunction formed between the metal–organic framework UIO-66(Hf)–NO2 and MoS2 enables the porous MOF to firmly pin the MoS2 onto the molecular chains of PVDF-HFP. During polarization, MoS2, being highly susceptible to the electric field, drives the movement of PVDF-HFP’s molecular chains through UIO-66(Hf)–NO2, this results in the molecular chains of PVDF-HFP aligning along the electric field, leading to a more orderly arrangement of the electric domains within PVDF-HFP and enhancing the piezoelectric effect, with the d33 value increasing from 8 pC N−1 to 27 pC N−1. The size of UIO-66(Hf)–NO2 is approximately 50 nm, with a conduction band of −0.93 eV and a bandgap of 2.56 eV, while MoS2 has a size of approximately 400 nm, a conduction band of −0.62 eV, and a bandgap of 1.27 eV. When MoS2 and UIO-66(Hf)–NO2 form a heterojunction, an interfacial electric field is generated at the junction, under the influence of this electric field, the PVDF-HFP molecular chains that penetrate into UIO-66(Hf)–NO2 tend to align, increasing the crystallinity of the composite nanofibers from 29.9 % to 35.0 %. This study broadens the application of heterojunctions formed by porous metal–organic frameworks with other conductors or semiconductors to enhance piezoelectricity, providing theoretical support.