Green Metal Organic Framework Research Articles

The Mechanism of Rapid and Green Metal–Organic Framework Synthesis by In Situ Spectroscopy and Diffraction

The Mechanism of Rapid and Green Metal–Organic Framework Synthesis by <i>In Situ</i> Spectroscopy and Diffraction

Fiber coating based on a green metal-organic framework to determine phthalates in bottled waters by direct-immersion micro solid-phase extraction

The metal-organic framework CIM-80(Al) is proposed as sorbent coating for solid-phase microextraction fibers. The novel CIM-80(Al)-based microextraction fibers (SPME) with a thickness of only 3.5 µm were used to isolate and determine 14 phthalate esters in bottled water with potential results. To compare the extraction efficiency of this novel green material with commercially available SPME fibers, several parameters of the overall procedure were setup. Different parameters such as pH, stirring speed, adsorption and desorption time, salting effect, and percentage of organic solvents were optimized. The results obtained with the CIM-80(Al) based-SPME fibers are promising and comparable to commercial coatings. It demonstrates similar results in a total of 16 bottled water samples subjected to determination. The detection and quantification were performed using ultra-high performance liquid chromatography-tandem mass spectrometer (UHPLC-MS/MS). The effectiveness of the proposed method was corroborated by its analytical characteristics such as limits of detection, which ranged from 0.01 to 0.5 µg L−1 while the linear range was 0.04 to 1 000 µg L−1. In terms of recoveries, CIM-80(Al)-SPME fiber provided results from 70 to 107 %, while the precision of the method in terms of relative standard deviation varied from 1.8 to 18.8 %.

MOF@Cell: 3D printed biobased filters anchored with a green metal–organic framework for effluent treatment

Multifunctional, biobased materials applicable within water treatment industry, produced through additive manufacturing technology.

Pesticide content analysis of red and yellow watermelon juices through a solid phase microextraction using a green copper-based metal-organic framework synthesized in water followed by a liquid phase microextraction procedure.

For the first time, this survey demonstrates the use of MIL-53 (Cu) in an analytical method for the detection and determination of some pesticides through their extraction and preconcentration from red and yellow watermelon juices. The other predominance of the research is using a green metal-organic framework that is based on copper and synthesized in deionized water. After conducting the synthesis process, Fourier transform infrared spectrophotometry, X-ray diffraction, scanning electron microscopy, and nitrogen adsorption/desorption analyses were carried out. In the analytical approach, the samples were accompanied by the sorbent addition and vortexed to facilitate the sorption of the analytes onto the sorbent and then centrifuged to be settled down. Then, the analyte-loaded sorbent particles were treated with mL-volume of acetonitrile and subjected to vortexing and centrifugation. Eventually, the eluate was mixed with μL-level of carbon tetrachloride and instantly injected into deionized water. The resulting milky solution was centrifuged and consequently, the sedimentation of the organic phase occurred at the bottom of the conical glass test tube. An aliquot of it was injected into a gas chromatograph equipped with flame ionization detector. Low limits of detection (0.85-1.24μgL-1) and quantification (2.80-4.10μgL-1), high enrichment factors (275-330), and reasonable extraction recoveries (55-66%) were the main achievements of the presented method. It is worthwhile to be confessed that chlorpyrifos was detected in red watermelon juice at a concentration of 27 ± 2μgL-1.

A breathing A4 paper by in situ growth of green metal–organic frameworks for air freshening and cleaning

Here, we prepared γ-CD-MOF@A4 nanocomposites through in-situ growth of γ-CD-MOFs on A4 printing paper for indoor air fresh and cleaning, including air pollutant capture, antibacterial, and fragrance encapsulation and release. Surface modification of natural cellulose fibers with nanomaterials is an effective strategy for producing functional textiles for multiple applications. A4-sized printing paper is a commonly used, cheap, and easily acquirable office supply which is mainly made of cellulose fibers. Here, we report green and simple nanofabrication of A4 paper to endow it with high capability for fragrance encapsulation and sustained release, and strong adsorption to indoor air pollutants. The method utilizes the sugar molecule of cellulose for in-situ growth of γ -cyclodextrin ( γ -CD) metal–organic frameworks (MOFs) on A4 paper. The obtained γ -CD-MOF/A4 nanocomposites have superior specific surface area and high porous structure. γ -CD-MOF/A4 nanocomposites can effectively encapsulate fragrant molecules through host-guest interaction. γ -CD-MOF/A4 nanocomposites also show strong absorption capability to formaldehyde and carbon dioxide through the formation of hydrogen bonding and chemical bond. The γ -CD-MOF/A4 nanocomposites combine the advantages of both A4 paper and γ -CD-MOF, which can be used in indoor air freshening and cleaning.

Hybrid Materials Formed with Green Metal-Organic Frameworks and Polystyrene as Sorbents in Dispersive Micro-Solid-Phase Extraction for Determining Personal Care Products in Micellar Cosmetics.

Hybrid materials based on polystyrene (PS) and green metal-organic frameworks (MOFs) were synthesized, characterized, and evaluated as potential sorbents in dispersive micro-solid-phase extraction (µ-dSPE). Among the resulting materials, the hybrid PS/DUT-67(Zr) was selected as the adequate extraction material for the monitoring of six personal care products in micellar cosmetic samples, combining the µ-dSPE method with ultra-high performance liquid chromatography (UHPLC) coupled to ultraviolet/visible detection (UV/Vis). Univariate studies and a factorial design were performed in the optimization of the microextraction procedure. The compromise optimum extraction conditions included 20 mg of PS/DUT-67(Zr) for 10 mL of sample, 2 min of extraction time, and two desorption steps using 100 µL of acetonitrile and 5 min assisted by vortex in each one. The validated μ-dSPE-UHPLC-UV/Vis method presented limits of detection and quantification down to 3.00 and 10.0 μg·L−1, respectively. The inter-day precision values were lower than 23.5 and 21.2% for concentration levels of 75 μg·L−1 and 650 μg·L−1, respectively. The hydrophobicity of the resulting PS/DUT-67(Zr) material was crucial for the improvement of its extraction capacity in comparison with its unitary components, showing the advantages of combining MOFs with other materials, getting new sorbents with interesting properties.

Unraveling the Origins of Strong and Reversible Chemisorption of Carbon Dioxide in a Green Metal–Organic Framework

Unraveling the Origins of Strong and Reversible Chemisorption of Carbon Dioxide in a Green Metal–Organic Framework

Electron diffraction for the promotion of stable and green metal–organic frameworks

Electron diffraction for the promotion of stable and green metal–organic frameworks

Toward Sustainable Li-Ion Battery Recycling: Green Metal–Organic Framework as a Molecular Sieve for the Selective Separation of Cobalt and Nickel

The growing demand for Li-ion batteries (LIBs) has made their postconsumer recycling an imperative need toward the recovery of valuable metals, such as cobalt and nickel. Nevertheless, their recovery and separation from active cathode materials in LIBs, via an efficient and environmentally friendly process, have remained a challenge. In this work, we approach a simple and green method for the selective separation of nickel ions from mixed cobalt–nickel aqueous solutions under mild conditions. We discovered that the bioinspired microporous metal−organic framework (MOF) SU-101 is a selective sorbent toward Ni2+ ions at pH 5–7 but does not adsorb Co2+ ions. According to the Freundlich isotherm, the adsorption capacity toward Ni2+ reached 100.9 mg·g–1, while a near-zero adsorption capacity was found for Co2+ ions. Ni2+ removal from aqueous solutions was performed under mild conditions (22 °C and pH 5), with a high yield up to 96%. The presence of Ni2+ ions adsorbed on the surface of the material has been proven by solid-state 1H nuclear magnetic resonance spectroscopy. Finally, the separation of Ni2+ from Co2+ from binary solutions was obtained with approximately 30% yield for Ni2+, with a near-zero adsorption of Co2+, which has been demonstrated by UV–vis spectroscopy. The ion adsorption process of Ni2+ and Co2+ ions was additionally studied by means of classical molecular dynamics calculations (force fields), which showed that the Ni2+ ions were more prone to enter the MOF canals by replacing some of their coordinated water molecules. These results offer a green pathway toward the recycling and separation of valuable metals from cobalt-containing LIBs while providing a sustainable route for waste valorization in a circular economy.

Adsorption of CO2 on amine-functionalized green metal-organic framework: an interaction between amine and CO2 molecules.

The efficient capture of CO2 is a critical problem for porous adsorbents. The inadequacy of conventional adsorbents has low adsorption capacity towards CO2 removal. Metal organic frame work has been considered as very effective for CO2 adsorption as it shows higher rate of CO2 adsorption at room temperature. In conventional amine processes, a comparatively high energy penalty is required, whereas a novel class of metal-organic framework by the combination of amine solvent have improve the potential of adsorption process and also the efficiency of separation. Amine-functionalized MOFs become more fascinated due to strong interaction between carbon dioxide and amine-functionalized MOF. A renewable green γCD-MOF was synthesized by using vapor diffusion method. Post-synthetic modification of γCD-MOF was done with piperazine and analyzed to expose its crystalline structure, morphology, and porous structure. The main aim of this paper is to enhance the CO2 adsorption by functionalization of inexpensive, green, nanoporous γCD-MOF and also to highlight the effects of amine-based functionalization towards potential application. Gravimetric CO2 adsorption isotherms for γCD-MOF, pip-γCD-MOF are reported up to 60 °C and found to follow a pseudo-second-order reaction. The pip-γCD-MOF confirms comparatively increased rapid adsorption rate of CO2 than that of γCD-MOF and desorption of CO2, and need less energy for regeneration. These results are the complete evidence of piperazine as an efficient amine group for increasing the CO2 adsorption uptake capacity.

Ultrasonic-Assisted Synthesis, Characterization, and Application of a Metal–Organic Framework: A Green General Chemistry Laboratory Project

An instructional research-like multiweek laboratory project for a second-semester introductory general chemistry laboratory course has been developed. The ultrasonic-assisted synthesis method using low cost commercial ultrasonic cleaners has the convenience of running multiple students’ reactions simultaneously. Taking advantage of short reaction time, the green metal–organic framework project has been developed to facilitate experimental synthesis, characterization, and application of a porous material and debriefing of results during a normal laboratory period (about 3 h/class). This project provides the opportunity for instructors to introduce students to the Twelve Principles of Green Chemistry, the environmental impact of chemistry, modern solid-state analytical techniques, and a research-like experience of materials science.

Highly thin film nanocomposite membrane based metal organic complexes for brackish water desalination

Recently metal organic frameworks MOFs incorporated thin film composite membranes had great attention in separation processes due enhancement porosity with excellent selectivity.In this work, binary and ternary complexes as a green metal organic framework were successfully prepared using carboxymethyl cellulose as a cluster organic linker. The two types of MOFs were embedded with different loading amount in the selective layer through interfacial polymerization. The prepared meso-fillers MOFs were characterized by SEM, FTIR and EDX. Also the membranes were characterized by SEM and separation assessments. The Results showed that the optimum loading MOFs was 0.1 wt%. Both binary complex MOF1 and ternary complex MOF2 were enhanced the performance of the membrane and the impact was depended on the MOFs loading amount. At the optimum MOFs loading amount 0.1 wt.%, the permeate flux increased from 30 LMH to 36 and 41 LMH, for the neat membrane, MOF1 and MOF2 membranes respectively. As well NaCl rejection was significantly affected and improved by embedding these MOFs, where NaCl rejection increased from 69% to 93% and 97% for neat membrane, MOF1 and MOF2 membranes respectively to 7000 ppm of NaCl at 5 bar feed pressure. The prepared membranes based MOF1 and MOF2 with 0.1 wt.% were tested for 60 days to confirm the stability of polyamide layer and their performance properties. The cubic like structure for the polyamide layer was observed by SEM images for 0.1% ternary complexes filled membrane so this study demonstrates that the MOFs based membrane is a promising technology on the laboratory mode for water desalination.

A green metal-organic framework to monitor water contaminants.

The CIM-80 material (aluminum(iii)-mesaconate) has been synthetized in high yield through a novel green procedure involving water and urea as co-reactants. The CIM-80 material exhibits good thermal stability with a working range from RT to 350 °C with a small contraction upon desolvation. Moreover, this material is stable in water at different pH values (1–10) for at least one week, and shows a LC50 value higher than 2 mg mL−1. The new material has been tested in a microextraction methodology for the monitoring of up to 22 water pollutants while presenting little environmental impact: only 20 mg of CIM-80 and 500 μL of acetonitrile are needed per analysis. The analytical performance of the CIM-80 in the microextraction strategy is similar to or even better for several pollutants than that of MIL-53(Al). The average extraction efficiencies range from ∼20% for heavy polycyclic aromatic hydrocarbons to ∼70–100% for the lighter ones. In the case of the emerging contaminants, the average extraction efficiency can reach values up to 70% for triclosan and carbamazepine.

Direct Calorimetric Measurement of Enthalpy of Adsorption of Carbon Dioxide on CD-MOF-2, a Green Metal–Organic Framework

The enthalpy of adsorption of CO2 on an environmentally friendly metal-organic framework, CD-MOF-2, has been determined directly for the first time using adsorption calorimetry at 25 °C. This calorimetric methodology provides a much more accurate and model-independent measurement of adsorption enthalpy than that obtained by calculation from the adsorption isotherms, especially for systems showing complex and strongly exothermic adsorption behavior. The differential enthalpy of CO2 adsorption shows enthalpy values in line with chemisorption behavior. At near-zero coverage, an irreversible binding event with an enthalpy of -113.5 kJ/mol CO2 is observed, which is followed by a reversible -65.4 kJ/mol binding event. These enthalpies are assigned to adsorption on more and less reactive hydroxyl groups, respectively. Further, a second plateau shows an enthalpy of -40.1 kJ/mol and is indicative of physisorbed CO2. The calorimetric data confirm the presence of at least two energetically distinct binding sites for chemisorbed CO2 on CD-MOF-2.

Strong and Reversible Binding of Carbon Dioxide in a Green Metal–Organic Framework

The efficient capture and storage of gaseous CO(2) is a pressing environmental problem. Although porous metal-organic frameworks (MOFs) have been shown to be very effective at adsorbing CO(2) selectively by dint of dipole-quadruple interactions and/or ligation to open metal sites, the gas is not usually trapped covalently. Furthermore, the vast majority of these MOFs are fabricated from nonrenewable materials, often in the presence of harmful solvents, most of which are derived from petrochemical sources. Herein we report the highly selective adsorption of CO(2) by CD-MOF-2, a recently described green MOF consisting of the renewable cyclic oligosaccharide γ-cyclodextrin and RbOH, by what is believed to be reversible carbon fixation involving carbonate formation and decomposition at room temperature. The process was monitored by solid-state (13)C NMR spectroscopy as well as colorimetrically after a pH indicator was incorporated into CD-MOF-2 to signal the formation of carbonic acid functions within the nanoporous extended framework.