Metal Organic Framework UiO-66 Research Articles

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.

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

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.

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.

Ab Initio Molecular Dynamics Investigation of Water and Butanone Adsorption on UiO-66 with Defects.

Volatile organic compounds (VOCs) are harmful chemicals that are found in minute quantities in the atmosphere and are emitted from a variety of industrial and biological processes. They can be harmful to breathe or serve as biomarkers for disease detection. Therefore, capture and detection of VOCs is important. Here, we have examined if the Zr-based UiO-66 metal-organic framework (MOF) can be used to capture butanone─a well-known VOC. Toward that end, we have performed Born-Oppenheimer ab initio molecular dynamics (AIMD) at 300 and 500 K to probe the energetics and molecular interactions between butanone [CH3C(O)CH2CH3] and open-cage Zr-UiO-66. Such interactions were systematically interrogated using three MOF structures: defective MOF with a missing 1,4-benzene-dicarboxylate linker and two H2O; pristine MOF with two H2O; and pristine dry MOF. These structures were loaded with one and four molecules of butanone to examine the effect of concentration as well. One-molecule loading interacted favorably with the defective structure at 300 K, only. In comparison, interactions with four-molecule loading were energetically favorable for all conditions. Persistent hydrogen bonds between the O atom of butanone, H2O, and μ3-OH hydroxyl attachments at Zr nodes substantially contributed to the intermolecular interactions. At higher loadings, butanone also showed a pronounced tendency to diffuse into the adjoining cages of Zr-UiO-66. The effect of such movement on interaction energies was rationalized using simple statistical mechanics-based models of interacting and noninteracting gases. Broadly, we learn that the presence of prior moisture within the interstitial cages of Zr-UiO-66 significantly impacts the adsorption behavior of butanone.

Harvesting Zr-based metal-organic frameworks by continuous-flow synthesis as efficient adsorbents for eliminating nitrogen-containing compounds in liquid fuel

This work designed a continuous-flow tubular reactor for rapidly and scalably harvesting the metal-organic framework (MOF) of UiO-66(Zr)-NH2. The experimental conditions, including temperature (110–140 °C), holding time (10–30 min), and CH3COOH/H2N-BDC molar ratio (100–250), were carried out to survey their impacts on the product yield and quality. The highest yield and production rate of ∼72% and ∼1.55 g h−1 were obtained at 130 °C, 20 min, and CH3COOH/H2N-BDC ratio 200. The temperature and modulator content significantly influenced MOFs’ crystal morphology, crystallinity, and porosity. Besides, the adopted method also successfully produced UiO-66 and UiO-67 MOFs with high production rates. The adsorptive denitrogenation (ADN) performances were carried out using liquid fuel models containing quinoline (QU) and 2-methyl pyrrole (MP). In batch mode adsorption, the UiO-66-NH2-130-200 sample showed the highest adsorbing quantities of ∼199 and ∼163 mg g−1 for QU and MP, respectively. Furthermore, the prepared MOFs efficiently removed NCCs from liquid fuel under a continuous fixed-bed column process. These demonstrate that modulator-assisted continuous-flow synthesis can be a potential strategy for the scalable harvest of Zr-MOFs with good qualities and high performance in getting rid of NCCs from liquid fuel.

Experimental Elucidation of a Cubane Water Cluster in the Hydrophobic Cavity of UiO-66.

Nanoscale water plays a pivotal role in determining the properties and functionalities of materials, and the precise control of its quantity and atomic-scale ordered structure is a focal point in nanotechnology and chemistry. Several studies have theoretically discussed the nano-ordered ice within one- or two-dimensional space and without confinement through hydrogen bonds. In particular, the water cluster has been predicted to play a significant role in biomolecules or functional nanomaterials; however, there has been little experimental evidence for their presence in hydrophobic cavities. In this study, the cubane water octamer - the most stable isomer among small water clusters - was detected within the hydrophobic cavities of UiO-66 metal-organic frameworks, revealing the presence of the smallest ice in their hydrophobic cavity, in the absence of hydrogen bonding. This observation contrasts earlier examples of water clusters confined within nanocavities through hydrogen bonds and provides experimental evidence for water-cluster capturing within hydrophobic cavities. Consequently, our renewed understanding of hydrophilicity and hydrophobicity warrants a design re-evaluation of materials for chemical applications, including fuel cells, water harvesting, catalysts, and batteries.

Slippery Liquid-Infused Porous Surfaces Containing UiO-66 Incorporated with 8-Hydroxyquinoline for Excellent Corrosion Protection of AZ31 Mg Alloys.

The conventional slippery liquid-infused porous surfaces (SLIPSs) provide relatively limited corrosion protection and self-healing performance for AZ31 Mg alloys. To this end, 8-hydroxyquinoline (8-HQ) was incorporated into a zirconium-based metal-organic framework UiO-66 through coordination (8-HQ@UiO-66), which was then dispersed into silicone oil to fabricate nanoparticle-enhanced-SLIPSs (8-HQ@UiO-66-SLIPSs). Especially, the influences of 8-HQ@UiO-66 concentration on the surface morphology, surface hydrophobicity, and corrosion resistance were studied. It was found that the surface hydrophobicity first increased and then decreased with increasing concentration, showing the highest water contact angle of 121.2° at a concentration of 1 mg mL-1 (8-HQ@UiO-66-SLIPS-1). This was attributed to the development of well-constructed hierarchical micro/nanostructures. Moreover, it also exhibited the best anticorrosion property, with the lowest corrosion current density of 1.24 × 10-10 A cm-2 and the highest impedance modulus of 9.88 × 108 Ω cm2 at 0.01 Hz, primarily associated with the synergistic interaction of 8-HQ and UiO-66. Further, the self-healing performance was evaluated using the scanning vibration electrode technique (SVET), verifying the superior self-healing performance of 8-HQ@UiO-66-SLIPS-1. Hence, the nanoparticle-enhanced-SLIPSs exhibit considerable potential in the corrosion protection of Mg alloys, thereby accelerating their extensive applications in industry.

CH4 Carbonylation to Acetic Acid Using H2O as an Oxidant on a Rh-Functionalized UiO-67 Combined with Oriented External Electric Fields: Selectivity and Mechanistic Insights from DFT Calculations.

Acetic acid (CH3COOH), as an industrially important petrochemical product, is predominantly produced via multistep energy-intensive processes. The development of a rhodium single-site heterogeneous catalyst has received considerable attention due to its potential to transform CH4 into CH3COOH in a single step. Herein, the reaction mechanism for the generation of CH3COOH from CH4, CO, and H2O catalyzed by Rh-functionalized metal-organic framework (MOF) UiO-67 and the selectivity of products CH3COOH, formic acid (HCOOH), methanol (CH3OH), and acetaldehyde (CH3CHO) under the oriented external electric fields (OEEFs) were systematically explored by density functional theory (DFT) calculations. The results reveal that the insertion of CO into Rh-CH3 is the rate-determining step with a free energy barrier of 21.0 kcal/mol in CH4 carbonylation to CH3COOH. Upon applying an OEEF of Fx = +0.0050 au along the C-C bond, the rate-determining step shifts toward H2O decomposition with the barrier of 19.6 kcal/mol, significantly improving the selectivity for CH3COOH production, compared to the major competitive HCOOH route. The Brønsted-Evans-Polanyi (BEP) relationships between key transition states, field strength, and NPA charge transfer were established. This study may guide the rational design of atomically dispersed MOF catalysts for the selective coconversion of CH4 and CO to CH3COOH using H2O as the oxidant under the OEEF.

UiO-67 MOF-Encapsulated NHC-Based Single-Site Copper Catalyst and Its Application in Regioselective Borylation of Terminal Alkynes.

N-Heterocyclic carbenes (NHCs) act as versatile ligand backbones due to their strong σ-donation and π-acceptance properties. However, the encapsulation of NHC-coinage metal complexes in a metal-organic framework (MOF) to utilize them in organic catalysis is rare. In this work, an NHC-coordinated CuBr (NHC = Bn2Im; 1,3-dibenzyl-imidazol-2-ylidene) complex was encapsulated in UiO-67 MOF ((Bn2Im)2CuBr@UiO-67) and further utilized toward the regioselective protoboration of terminal alkynes. (Bn2Im)2CuBr@UiO-67 was found to show superior catalytic performance in aiding the protoboration of terminal alkynes, with a very high turnover frequency (TOF) of 14333.3 h-1, much higher than those of many other reported copper-based heterogeneous catalysts. Our catalyst also retained excellent catalytic efficiency for up to five cycles for the above-mentioned process. The newly synthesized (Bn2Im)2CuBr@UiO-67 and the recovered catalyst post-catalysis were characterized using various analytical techniques, including powder X-ray diffraction (PXRD), IR spectroscopy, field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), and X-ray photoelectron spectroscopy (XPS).

Chitosan-polyethersulfone mixed matrix composite membranes utilizing amine and non-amine hafnium-MOFs for enhanced CO2 separation

Exploring the realm of advanced membranes with customizable separation capabilities holds great promise in CO2 separation. A particularly exciting path is the utilization of mixed matrix membranes (MMMs) to surpass the performance of commonly used polymeric membranes. In recent times, there has been a surge of interest in hafnium (Hf) metal–organic frameworks (MOFs) due to their multiple potential sites for CO2 adsorption. These MOFs feature four bridging hydroxyl groups (μ3-OH) positioned at the corners of the tetrahedral cavity, electronegative linker moieties, and Bronsted acid sites arising from undercoordinated metals. In this study, we synthesized task-specific UiO-66(Hf) and UiO-66-NH2(Hf) MOFs and integrated them into a chitosan (CS) matrix to explore their effects on CO2 separation performance of MMMs. Comprehensive analyses using various analytical techniques were conducted on synthesized MOFs and MMMs. At an optimal loading of 5 wt% of UiO-66-NH2(Hf) under humid conditions, the MMMs demonstrated a remarkable 408 % increment in CO2 permeance and a 113 % improvement in CO2/N2 selectivity compared to unfilled CS membranes. Notably, the UiO-66-NH2(Hf) MOF, enriched with amino ligands, exhibited superior dispersibility and enhanced CO2 separation ability compared to the UiO-66(Hf) MOF within the CS matrix. These findings not only approach the 2008 Robeson upper bound curve but also demonstrate consistency in the CO2 separation performance for over 120 hours of exposure at elevated temperatures (85°C) and a feed pressure of 2.21 bar under humid conditions. These challenging conditions, mirroring real-world applications, highlight the stability of the synthesized MMMs as efficient gas separation technologies.

Dispersive solid phase extraction of chloramphenicol and florfenicol in honey sample performed in narrow bore tube with the aid of magnetic ionic liquids prior to HPLC-DAD analysis

The precedence of high levels of antibiotics in animal-derived foods such as honey poses a significant food safety risk. Therefore, the development of an accurate, and reliable method for determining these residues is crucial. In this study, a new extraction method was proposed for the simultaneous determination of chloramphenicol and florfenicol residues in honey samples prior to high performance liquid chromatography analysis. The method involved using amino-functionalized UiO-66 metal–organic framework (NH2-UiO-66) as a sorbent in a narrow bore tube. To begin, the solution was placed into a narrow bore tube and the pH was adjusted to 6. Then, 100 mg of the sorbent was added to the solution. The particles were slowly passed through the solution and collected in the tube bottom. After removing the supernatant phase, 55 µL of 1-butyl-3-methylimidazolium tetrachloroferrate (III) magnetic ionic liquid was used as the elution solvent under sonication for 3 min. The optimized method exhibited low limits of detection (0.19 and 0.44 ng g−1) and quantification (0.63 and 1.4 ng g−1), good extraction recovery (81 and 74 %), and good linearity of the calibration curve (r2 ≥ 0.996) over the ranges of 1.2–500 and 2.4–500 ng g−1 for florfenicol and chloramphenicol, respectively. Precision was satisfactory, with relative standard deviations ≤8.1 % for both intra- and inter-day precisions. The developed method was done on ten honey samples and chloramphenicol was found in five samples.

Exploring performance and mechanism of modified metal-organic frameworks in calcium alginate/polyvinyl alcohol double-network hydrogels for effective dye wastewater treatment

To address the growing problem of dye wastewater pollution, a novel MOFs adsorbent calcium alginate/polyvinyl alcohol@UiO-66 was developed using environmentally friendly polymers, sodium alginate and polyvinyl alcohol creating gel spheres with a double-network structure through cross-linking. UiO-66 metal-organic frameworks are then grown onto the gel spheres, resulting in the final CA/PVA@UiO-66 adsorbent. This adsorbent boasts a high surface area (17.4 m2/g) and a mesoporous-nested microporous structure. It effectively removes MB from water, the actual maximum adsorption capacity was measured at 275.8 mg/g, which surpasses most existing adsorbents. Remarkably, the adsorbent retains 93.9 % of its initial capacity even after 10 reuse cycles. The adsorption process adhered to the Redlich-Peterson model and the PFO model. The N2-Sorption isotherm, actual Methylene blue (MB) adsorption experiments, and model analysis further suggest that the adsorption process is a complex heterogeneous diffusion process involving simultaneous chemical and physical adsorption. Additionally, the adsorption process is endothermic, indicating that it can occur spontaneously at 298 K. Increasing the temperature promotes the forward progress of the adsorption reaction, thereby enhancing the adsorption capacity. The gel adsorbent exhibited excellent dye wastewater purification capabilities, coupled with commendable reusability.

Engineering the defects of UiO-66 MOF for an improved catalytic detoxification of CWA simulant: methyl paraoxon.

Exigency in search of an ideal candidate for an effective detoxification of chemical warfare agents is still continuing. Zirconium-based Metal-organic Framework (MOF) UiO-66 has shown a significant detoxification of such toxic chemicals owing to its tunable physio-chemical properties and profuse catalytic sites. In this context, a series of UiO-66 MOFs synthesized by tuning the acidity constant (pK a) and concentration of the modulator, synthesis temperature and water molecules was tested for their detoxification efficiency against the simulant 'methyl-paraoxon' at room temperature. Amongst, HCl modulated UiO-66 across the considered synthesis temperature have shown competent catalytic performance in virtue of defects generation within its structure. In addition, the role of catalytic features of UiO-66 obtained by tailoring its defects in enhancing the degradation efficiency has been systematically investigated. The detoxification efficiency of 98.5% with a half-life time of 0.23 min has confirmed the effectiveness of engineered defects in enhancing the catalytic activity of UiO-66 in detoxifying the identified simulant.

Evaluation and Comparison of UiO66 and Its Functionalized Variants for the Removal of Cu (II) Ions from Wastewater

This study examined the effectiveness of polyvinyl chloride (PVC) mixed matrix membranes incorporating UiO66 and UiO66-NH2 metal-organic frameworks (MOFs) for removing varying concentrations of Cu (II) ions from wastewater. The findings indicated that adding UiO66-NH2 to the functionalized UiO (FUiO) membrane enhanced its porosity, pore size, hydrophilicity, and pure water flux. Furthermore, integrating UiO66-NH2 into the PVC matrix led to an impressive Cu (II) ion removal efficiency exceeding 99%. The PVC-FUiO2 membrane also demonstrated about 93.5% reusability after the first cycle. Overall, the results confirmed that the PVC-FUiO2 (Functionalized UiO66) membrane exhibited superior performance in terms of Cu (II) removal efficiency and shorter separation times across various Cu (II) concentrations compared to the unmodified membrane.

Enhancing oxidative desulfurization catalytic performance of metal–organic frameworks UiO-66 (Zr) by post-synthetic with the creation of active sites

It is being explored to utilize two types of Zr-based metal–organic frameworks, bimetallic V/Zr-UiO-66 and functionalized UiO-66 by Vanadium (Zr-UiO-66-V), as heterogeneous catalysts in oxidative desulfurization processes. The bimetallic MOFs’ inorganic nodes contain two distinct ions; compared to their monometallic counterparts, these MOFs have a synergistic impact and improved characteristics. Innovative bimetallic MOFs provide additional options for further customizing the attributes of MOFs, which have drawn significant interest for various applications. On the other hand, the functionalization of MOFs further enhances the MOFs’ catalytic activity where V ions replace H+ in the –OH group in the zirconium-based node. Compared to UiO-66 (Zr), these techniques may significantly improve the efficacy of oxidative desulfurization. For the synthesized V/Zr-UiO-66 and Zr-UiO-66-V, having essential properties such as surface area (1287, 1392 m2/gr), pore volume (0.89, 0.93 cm3/gr), removal of DBT in model oil could reach > 91.4 % and > 97.7 % within 2.5 h at 343 K, respectively, which is 1.41 and 1.5 times as much as for parent UiO-66 (Zr). Furthermore, the heterogeneous catalyst displayed excellent thermal and chemical stability, and the DBT conversion efficiency remained > 78.9 % after six recycling cycles. Performance improvement is primarily attributable to the incorporation of active V sites.

Harnessing nanotechnology for breast cancer management: UiO-66 (NH2) metal-organic frameworks functionalized with chitosan and folic acid for the efficient delivery of doxorubicin

Cancer is a leading cause of morbidity globally, which could be due to a lack of effective treatments. The inherent inadequacies of traditional medicines in terms of tumour selectivity and undesired toxicity urge us to seek alternative therapies to address these drawbacks. Metalorganic frameworks (MOFs) have been synthesized for use in drug delivery systems (DDS) because of their improved porosity and larger specific surface area. In this research, UiO-66-NH2 MOFs were synthesized via a solvothermal technique and functionalized with chitosan-folic acid (CS-FA) as a DDS for targeted doxorubicin (DOX) delivery. The MOF nanoplatforms were characterized via different techniques, including FTIR, PXRD, BET, TEM, DLS, TGA, SEM, and TGA. Remarkably, compared with the unmodified MOF, UiO-DOX@CS-FA delayed DOX release due to a gated effect induced by the CS-FA surface coating. pH-sensitive DOX release was observed, where 39.76 % of the drug was released in the tumour-mimicking pH of 5.2, whereas 5.84 % of the drug was released at physiological pH (7.4). In vitro cellular toxicity and uptake investigations demonstrated that UiO-DOX@CS-FA is a highly effective targeted DDS against MCF-7 breast cancer cells. Furthermore, in vivo toxicity studies in Wistar rats revealed no evidence of serious adverse effects. The variety of pharmacokinetic characteristics tested indicated that the bioavailability and release kinetics of DOX improved. Our findings lay the groundwork for the development and production of novel polymer conjugate-based nanoparticles with increased tumour-targeting efficacy.

Enhancing the electrochemical properties of polyethylene oxide solid-state electrolytes based on a small nano-sized UiO-66 metal-organic framework

Metal-organic frameworks (MOFs) have garnered significant attention in the field of Lithium-ion batteries due to their porous periodic network properties. However, this is a challenge to design high-performance solid-state electrolytes reasonably. Herein, a small nano-sized MOF Small-UiO-66 is reported, which has high surface area and mesoporous properties that can effectively inhibit PEO matrix crystallization. The presence of Small-UiO-66 accelerates the dissociation of lithium salts, which disrupts the ordered arrangement of the PEO chain segments. The abundant Lewis acidic sites on the surface of Small-UiO-66 facilitate the construction of abundant Li+ transport channels and promote Li+ conduction. Furthermore, the smaller nano-sized increase the interfacial wettability with lithium metal, which promotes the uniform diffusion of Li+ and inhibits the growth of lithium dendrites. The results indicate that 0.1 Zr-CSE exhibits high ionic conductivities of 6.94 × 10−4 S/cm at 60 °C. Based on 0.1 Zr-CSE, the Li||Li symmetric cell can operate stably for 1200 h at a current density of 0.1 mA/cm2, and the LFP||Li cell also achieves a high initial capacity of 147.65 mAh·g−1 at current densities of 0.5C. This work presents a novel approach for preparing high-performance solid-state Lithium-ion batteries using MOFs as fillers for polymer solid-state electrolytes.

UiO-66 Inspired Superhydrophobic Coatings Fabricated from Discarded Polyester/Spandex Textiles.

We report on a method for synthesizing superhydrophobic coatings using a UiO-66 metal-organic framework (MOF) with discarded polyester/Spandex fabrics as raw materials. Unlike traditional recycling techniques that involve separating non-poly(ethylene terephthalate) (PET) components, our approach directly uses blended polyester/Spandex fibers. Discarded polyester/Spandex fabrics were exposed to an alkaline depolymerization process to produce disodium terephthalate (Na2BDC), which is a known linker for UiO-66 synthesis. We conducted experiments under two different conditions involving different amounts of ethanol. We found that with a small amount of ethanol, the resulting UiO-66 structure, when assembled on top of a polyester/Spandex substrate, exhibited a water contact angle of ≥150°─a superhydrophobic behavior. When using larger amounts of ethanol, we noted a hydrophobic behavior with a water contact angle of ∼139°. As a control, we performed the same experiments but using discarded 100% polyester fabrics as raw materials, which resulted in a superhydrophilic behavior. We attribute the superhydrophobic behavior of the UiO-66 coatings, produced from the polyester/Spandex fabrics, to the presence of hydrophobic compounds generated by the chemical degradation of Spandex. Our approach introduces a pathway for upcycling discarded textiles into superhydrophobic coatings.

Pyrolytic Depolymerization of Polyolefins Catalysed by Zirconium-based UiO-66 Metal-Organic Frameworks.

Polyolefins such as polyethylenes and polypropylenes are the most-produced plastic waste globally, yet are difficult to convert into useful products due to their unreactivity. Pyrolysis is a practical method for large-scale treatment of mixed, contaminated plastic, allowing for their conversion into industrially-relevant petrochemicals. Metal-organic frameworks (MOFs), despite their tremendous utility in heterogeneous catalysis, have been overlooked for polyolefin depolymerization due to their perceived thermal instabilities and inability of polyethylenes and polypropylenes to penetrate their pores. Herein, we demonstrate the viability of UiO-66 MOFs containing coordinatively-unsaturated zirconium nodes, as effective catalysts for pyrolysis that significantly enhances the yields of valuable liquid and gas hydrocarbons, whilst halving the amounts of residual solids produced. Reactions occur on the Lewis-acidic UiO-66 nodes, without the need for noble metals, and yield aliphatic product distributions distinctly different from the aromatic-rich hydrocarbons that can be obtained from zeolite catalysis. We also demonstrate the first unambiguous characterization of polyolefin penetration into UiO-66 pores at pyrolytic temperatures, allowing access to the abundant Zr-oxo nodes within the MOF interior for efficient C-C cleavage. Our work highlights the potential of MOFs as highly-designable heterogeneous catalysts for depolymerisation of plastics, which can complement conventional catalysts in reactivity.