Copper-based Metal-organic Framework Research Articles

CuMOF-decorated biodegradable nanofibrous membrane: facile fabrication, high-efficiency filtration/separation and effective antibacterial property

Here, a multifunctional poly (lactic acid)/copper-based metal–organic framework (PLA/CuMOF) degradable composite membrane featuring superior antibacterial and self-cleaning properties was fabricated via a simple electrospinning process for high- efficiency filtration/separation. Benefiting from the decrease of fiber diameter, the improved surface roughness and the surface charge of CuMOF, PLA/CuMOF fibrous membrane achieved excellent capture ability for ultra-fine particles and superb purification capability for real PM2.5 smoke. The differences of filtration capacity between PLA membrane and PLA/CuMOF membrane was furtherexplored using analoguesimulation with dynamic particle capture and airflow field distribution. Impressively, PLA/CuMOF fibrous membrane combines robust self-cleaning ability, effective antibacterial effect, and thermal management capability. Moreover, owing to the special selective wettability and chemical stability, PLA/CuMOF membrane possessed the stable oil–water separation performance under harsh environment (e.g., high acid, alkali, and salt). This degradable multifunctional filtration/separation fibrous membrane emerges a broad application prospect ranging from environmental governance, industrial security to personal protection.

Development of an electrochemical fentanyl nanosensor based on MWCNT-HA/ Cu-H3BTC nanocomposite

Fentanyl is a potent narcotic drug with the same effects as morphine or heroin, but it’s significantly more potent than these drugs. That means a tiny dose can have a dangerous impact and is also lethal, so it is essential to measure it. In this work, we have developed a new electrochemical sensor to measure this deadly drug utilizing a nanocomposite of multi-walled carbon nanotube, hydroxyapatite, and copper-based metal–organic framework (MWCNT-HA/Cu-H3BTC). The nanocomposite was first examined by X-ray diffraction, field emission scanning electron, Infrared, and Raman spectroscopic techniques. The glassy carbon electrode (GCE) modified with MWCNT-HA/Cu-H3BTC was employed to determine fentanyl in aqueous solutions. The highest oxidation current was generated for fentanyl at GCE/MWCNT-HA/Cu-H3BTC compared to the GCE, GCE/MWCNT, GCE/MWCNT/HA, and GCE/Cu-H3BTC. The GCE/MWCNT-HA/Cu-H3BTC showed a linear relationship between the concentration and the oxidation current of fentanyl in the 0.01 to 100 μM with a detection limit of 3 nM. Finally, the fentanyl quantification in blood serum samples was successfully performed. The GCE/MWCNT-HA/Cu-H3BTC's reproducibility and stability were indeed excellent.

Synthesis of metal-organic framework HKUST-1 via tunable continuous flow supercritical carbon dioxide reactor

Scaling-up synthesis of metal–organic framework (MOF) materials is critical for their practical applications. Due to its unique properties, supercritical carbon dioxide (scCO2) is an attractive media single-step synthesis of MOFs. This paper, for the first time, presents a rapid synthesis of the high-quality copper-based MOF HKUST-1 in a continuous flow scCO2 flow reactor, evaluating the effects of pressure, scCO2 injection temperature, scCO2 mass fraction, and the reactor residence time on HKUST-1 properties over 23 experiments. The morphology, crystallinity, and porosity of MOF are characterized by scanning electron microscopy, X-ray diffraction, and physisorption analysis. Four sets of experiments showed excellent repeatability in particle size and specific surface area yielding high-quality HKUST-1 MOFs. The particle sizes ranged from 55 to 300 nm with an average of 135 nm, and the BET surface -- from 1,374 to 2,389 m2·g−1 with an average of 1,712 m2·g−1. Longer residence time increased particle size and led to MOF shape change from spherical to octahedral; however, these did not significantly correlate with MOF surface area. Pressure variation in the 8–10 MPa range did not impact HKUST-1 properties. Reactant temperature variations between 80 and 120 °C showed a weak correlation with particle size. Increasing reactor section temperature independently of the reactant temperature had a statistically significant negative correlation to particle size, r-value = -0.86, and p-value = 0.04. The scCO2-assisted synthesis yielded high-quality MOFs under all studied conditions with residence time in the range of 70–170 s, demonstrating the robustness and high throughput of the method.

Filling Mesopores of Conductive Metal-Organic Frameworks with Cu Clusters for Selective Nitrate Reduction to Ammonia.

The electrocatalytic nitrate reduction reaction (NO3-RR) to ammonia (NH3) under ambient conditions not only has the benefit of lowering energy consumption, but also helps remove nitrate contamination. Inspired by the unique structure of nitrate/nitrite reductase with the active spheroproteins encapsulated by larger enzymes, herein, we develop an in situ synthetic strategy for the construction of metal cluster-conductive metal-organic framework (MOF) composite electrocatalysts. The metallic Cu clusters are filled into the mesopores of a conductive copper-based MOF (i.e., CuHHTP); meanwhile, CuHHTP with a porous structure provides an internal environment to limit the growth of metallic Cu clusters with an ultrasmall size (i.e., 1.5 ± 0.2 nm) and restrains their aggregation. The obtained Cu@CuHHTP exhibits superb performance for NO3-RR. In a neutral electrolyte with 500 ppm NO3-, Cu@CuHHTP shows a high NO3- conversion of 85.81% and a selectivity for NH3 of 96.84%. 15N isotope labeling experiments confirm that the formation of NH3 originates from the process of NO3-RR. Theoretical calculations confirm that Cu clusters are the active sites in the composite electrocatalysts, in which the proper d-band center and the "accept-donate" mechanism in charge transfer are the key factors for the improvement of the electrocatalytic performance.

Development and Blood Compatibility of a Stable and Bioactive Metal-Organic Framework Composite Coating for Blood-Circulation Tubing.

Medical devices that require substantial contact between blood and a foreign surface would be dramatically safer if constructed from materials that prevent clot formation and coagulation disturbance at the blood-biomaterial interface. Nitric oxide (NO), an endogenous inhibitor of platelet activation in the vascular endothelium, could provide anticoagulation at the blood-surface interface when applied to biomaterials. We investigated an application of a copper-based metal-organic framework, H3[(Cu4Cl)3(BTTri)8-(H2O)12]·72H2O where H3BTTri = 1,3,5-tris(1H-1,2,3-triazole-5-yl)benzene] (CuBTTri), which has been shown to be an effective catalyst to generate NO from S-nitrosothiols that are endogenously present in blood. A method was developed to apply a CuBTTri composite coating to Tygon medical tubing used for extracorporeal lung support devices. The stability and activity of the coating were evaluated during 72 h dynamic saline flow testing (1.5-2.5 L/min, n = 3) with scanning electron microscopy imaging and inductively coupled mass-spectroscopy analysis. Compatibility of the coating with whole blood was assessed with a panel of hemocompatibility tests during 6 h circulation of swine donor blood in an ex vivo circulation loop constructed with CuBTTri tubing or unmodified Tygon (1.5 L/min blood flow rate, n = 8/group). Thrombus deposition and catalytic activity of the CuBTTri tubing were assessed following blood exposure. The coating remained stable during 72 h saline flow experiments at clinically relevant flow rates. No adverse effects were observed relative to controls during blood compatibility testing, to include no significant changes in platelet count (p = 0.42), platelet activation indicated by P-selectin expression (p = 0.57), coagulation panel values, or methemoglobin fraction (p = 0.18) over the 6 h circulation period. CuBTTri within the coating generated NO following blood exposure in the presence of biologically relevant concentrations of an NO donor. CuBTTri composite coating was stable and blood compatible in this pilot study and requires further investigation of efficacy using in vivo models conducted with clinically relevant blood flow rates and study duration.

N,N-Diethyl-3-methylbenzamide

The development of new techniques for the preparation of organic compounds is important, with catalytic processes being key to this innovation. The development of copper-based metal-organic frameworks to promote oxidative couplings has allowed the synthesis of amides in a very effective manner. This methodology has been successfully applied to the unique preparation of the bioactive compound N,N-diethyl-3-methylbenzamide, with excellent performance (>99% conversion and 95% yield of pure isolated product) on a preparative scale. The described procedure can be classified as an excellent synthesis (EcoScale) considering environmental and economic factors based on different “green metrics” (atom economy, reaction mass efficiency, materials recovery factor, stoichiometric factor, E-factor).

High-performance scavenging of Nd (III) and Sm (III) from water by a copper-based metal-organic framework HKUST-1

High-performance scavenging of Nd (III) and Sm (III) from water by a copper-based metal-organic framework HKUST-1

Fabricating effective heterojunction in metal-organic framework-derived self-cleanable and dark/visible-light dual mode antimicrobial CuO/AgX (X = Cl, Br, or I) nanocomposites

Owing to the alarming consequences of antimicrobial resistance, the requirements for effective antimicrobial materials working under dark and visible-light conditions are on the high rise. On a different note, heterojunctions between semiconductors are highly desirable to enhance the photocatalytic activity of the individual components in a synergistic way. In this work, we address these two aspects in a single material composition through a rationally designed synthetic strategy. Among several candidates, silver and copper are known to exhibit high antimicrobial characteristics in the dark. Besides, CuO and silver halides are known for their visible-light photocatalytic activity. Hence, a copper-based porous metal organic framework, Cu-BTC, has been deposited with a silver halide followed by calcination to yield CuO/AgX (X = Cl, Br, or I) nanocomposites. The initial deposition of the silver halide over the MOF is envisaged to provide a high dispersion of the halide in the CuO matrix through numerous anchoring pods and thereby result in a tight and effective heterojunction. The nanocomposites obtained through this approach have been characterized structurally and morphologically using various techniques. The nanocomposites have been studied for their visible-light photocatalytic and self-cleaning ability via photodegradation of methylene blue and 4-chlorophenol as model systems. Further, their antimicrobial efficacy has been studied against E. coli and S. aureus both under dark and visible-light conditions. In addition to revealing the high potential of the CuO/AgX nanocomposites towards environmental applications, the synthetic approach presented herein can potentially be extrapolated to fabricate exotic compositions possessing enhanced efficacy.

Hierarchical NiCo2O4/CuO-C nanocomposite derived from copper-based metal organic framework and Ni/Co hydroxides: Excellent electrocatalytic activity towards methanol oxidation

In this work, a metal-organic framework (Cu-MOF) and two none-precious metals (Ni and Co) are used for preparation of a highly efficient electrocatalyst for methanol oxidation reaction. Nickel/cobalt hydroxides are coprecipitated on Cu-MOF in alkaline solution. The composite is then calcinated at 350 °C to obtain a carbonaceous framework and flower-like NiCo2O4 deposits (CuO-C/NiCo2O4). The obtained composite is characterized by several methods (XRD, XPS, FT-IR, SEM, TEM, and electrochemical techniques). The presence of metal oxides CuO and NiCo2O4 in the prepared electrocatalyst is confirmed by XRD and XPS methods. CuO-C/NiCo2O4 shows excellent catalytic activity towards MOR in alkaline solution (NaOH, 1 M). The electrocatalytic activity of CuO-C/NiCo2O4 is compared to stepwise composites (CuO-C/NiO, CuO/CoO, NiCo2O4) and commercial Pt/C, which confirms the superiority of the proposed catalyst in terms of current density (208.1 mA cm−2) and amperometric stability (7000 s) in methanol oxidation reaction. The observed benefits are attributed to synergistic effects between the porous conductive carbonaceous material and multi transition-metal oxides (CuO and NiCo2O4).

Efficacious bioconversion of waste walnut shells to xylotetrose and xylopentose by free xylanase (Xy) and MOF immobilized xylanase (Xy-Cu-BTC)

This study uses a cost effective and efficient method for production of higher DP (degree of polymerization) Xylooligosaccharides (XOS) from xylan extracted from the waste walnut shells. Copper based metal organic framework (Cu-BTC MOF) was prepared for immobilization of free xylanase (Xy) enzyme by green synthesis method. Both free and immobilized xylanase (Xy-Cu-BTC) were able to cause the bioconversion of xylan (87.4% yield) into XOS. Predominant production of xylotetrose (X4) and xylopentose (X5) was observed for both the methods. Percentage XOS conversion for free enzyme (Xy) was found to be 4.1% X4 and 60.57% X5 whereas these values increased in case of immobilized system where 11.8% X4 and 64.2% X5 were produced. Xylose production was minute in case of immobilized xylanase 0.88% which makes it a better method for XOS production free from xylose interference. Xy-Cu-BTC MOF can hence be used as an attractive alternative for pure XOS production.

A copper-based metal-organic framework for upgrading natural gas through the recovery of C2H6 and C3H8

Natural gas processing involves the separation of higher hydrocarbons (C2–C3) from methane, which is an important and energy-intensive operation. In this paper, we present a comprehensive study of an innovative copper-based MOF (Cu-MOF) for the separation of propane and ethane from methane. The material exhibits a high adsorption capacity and selectivity for C2–C3 hydrocarbons over methane, which is primarily due to its preferential C2–C3 hydrocarbon adsorption. The adsorption isotherms at ambient conditions showed a remarkable uptake of C3H8 of 134.0 cm3/g, as well as excellent selectivity of 204 and 9 for C3H8/CH4 and C2H6/CH4. According to the theoretical calculations, differences in van der Waals interactions and polarizability of the guest molecules were responsible for influencing separation performance. In addition, we conducted adsorption kinetic experiments, dynamic breakthrough, and cycling experiments to further examine the separation performance. Overall, this research establishes an energy-efficient adsorbent for upgrading natural gas.

Copper-Based Metal-Organic Framework with a Tetraphenylethylene-Tetrazole Linker for Visible-Light-Driven CO2 Photoconversion.

The design of efficient and inexpensive photocatalysts for CO2 photoreduction under visible light is of great significance for the sustainable development of the entire society. Herein, a copper-based metal-organic framework (MOF) (CUST-804) using a bulky tetraphenylethylene-tetrazole linker is synthesized and successfully used as a photocatalyst for CO2 reduction. The structural characterizations, as well as the photophysical properties, are investigated systematically. In the heterogeneous catalytic system, CUST-804 exhibits a robust CO production activity up to 2.71 mmol g-1 h-1 with excellent recyclability along with a selectivity of 82.8%, which is comparable with those of the reported copper-based MOF system. Theoretical calculations demonstrated that, among three kinds of coordinated model, only the 5-coordinated Cu site is active for CO2 reduction, in which the *COOH intermediate is stabilized and CO is readily desorbed. The results obtained herein can provide fresh insights into the realization of efficient copper-functionalized crystalline photocatalysts for CO2 reduction.

Three-dimensional graphene-like homogeneous carbon architecture loaded with gold-platinum for the electrochemical detection of circulating tumor DNA

The analysis of circulating tumor DNA (ctDNA) turns out to be increasingly significant considering its potential value in the clinical diagnosis of cancer. Herein, a ctDNA electrochemical biosensor was developed with a low detection limit and high selectivity by using three-dimensional graphene-like homogeneous carbon architecture (3D-GHC600) loaded with gold-platinum (AuPt). The 3D-GHC600 was derived from the annealing process of copper-based metal-organic framework (denoted as Cu-BTC) at the optimal temperature (600 °C), which includes the merits of large area, rich mesopores, homogeneous size and morphology, and 3D structure. AuPt was formed on the 3D-GHC600 surface via an in-situ reduction reaction. Characterizations demonstrated that the resultant composite catalyst (AuPt/3D-GHC600) was prepared successfully and exhibited remarkable electrochemical properties. Further, the catalyst was used as a label of signal probes (SPs) to form SPs-label. The hybridization reactions were completed by layer-by-layer recognition of capture probes (CPs), target DNA (tDNA), and SPs-label on the electrode, thus forming a sandwich-like structure. The current signals of the SPs-label toward the electrocatalytic reduction of H2O2 were recorded in all tests for tDNA analysis. Accordingly, this recommended biosensor of tDNA showed good performance including a wide linear range of 10−8 M − 10−17 M with a detection limit of 2.25 × 10−18 M (S/N = 3), excellent selectivity for the recognition of different interferences, satisfying reproducibility, good stability, and outstanding recovery. These results demonstrated the promising application of the biosensor in the detection of ctDNA.

Understanding Solvothermal Growth of Metal-Organic Framework Colloids for CO2 Capture Applications.

A quantitative study of the synthesis of metal-organic framework (MOF) colloids via a solvothermal growth process was demonstrated using electrospray-differential mobility analysis (ES-DMA), a gas-phase electrophoresis approach. HKUST-1, a copper-based MOF (Cu-MOF), was selected as the representative MOF of the study. The effects of the synthetic parameters, including ligand concentration (CBTC), synthetic temperature (Ts), and synthetic time (ts) versus material properties of the Cu-MOF, were successfully characterized based on the mobility size distributions measured by ES-DMA. The results show that the mobility size of Cu-MOF was proportional to Ts, ts, and CBTC during the solvothermal growth. X-ray diffraction and Brunauer-Emmett-Teller analyses were employed complementarily to the ES-DMA, confirming that the increase in mobility size of Cu-MOF was correlated to the increase in crystallinity (i.e., larger specific surface area and crystallite size). The results of CO2 pulse adsorption show that the synthesized Cu-MOF possessed a good CO2 adsorption ability under 1 atm, 35 °C, and the cumulative amount of CO2 uptake was proportional to the measured mobility size of Cu-MOF. The work provides a proof of concept for the controlled synthesis of MOF colloids with the support of gas-phase electrophoretic analysis, and the quantitative methodology is useful for the development of MOF-based applications in CO2 capture and utilization.

Balancing uptake and selectivity in a copper-based metal–organic framework for xenon and krypton separation

Efficient separation of Xenon (Xe) and krypton (Kr) is important in the gas industries but remains challenging. Adsorptive separation affords an energy-efficient method to isolate the two noble gases, yet developing selective adsorbents with high uptake and excellent selectivity remains difficult, limited by a trade-off between uptake and selectivity. We report MOF-11 with optimal pore size and accessible open metal sites (OMSs) for separation of Xe over Kr via the discriminable difference in van der Waals interactions. MOF-11 affords a new benchmark for Xe/Kr separation with high Xe uptakes of 4.05 and 4.95 mmol/g (at 0.2 and 1 bar), high Xe/Kr Henry and IAST selectivity (13.6 and 16.1) at 298 K. Evidenced by Xe-loaded structure, multiple Xe···H interactions between Xe and the terminal H atoms allow Xe atoms firmly packed within the framework. This work demonstrates a strategy for balancing uptake and selectivity in Xe/Kr separation by capitalizing on the synergy between optimal pore size and OMSs.

Synthesis of Cu-MOF/CeO2 nanocomposite and their evaluation of hydrogen production and cytotoxic activity

In this investigation, new composites of cerium oxide were incorporated in the copper-based metal–organic framework using trimesic acid by the precipitation method. Synthesized Cu-MOF/CeO2 nanocomposite is characterized by numerous analytical methods to interpret their structure, morphology, and thermal behaviour. Surface micrograph analysis revealed that spherical particles and cerium oxide nanoparticles are embedded in the Cu-MOF matrix. The prepared nanocomposite shows a lesser onset potential and overpotential with a high current density (18.6 mA cm−2). The Cu-MOF/CeO2 composite exhibits a small Tafel slope of 54.6 mV dec-1 and suggests that the hydrogen evolution reaction follows the Heyrovsky mechanism. On the other hand, five different MOF/CeO2 nanocomposite concentrations were tested on a human osteosarcoma cell line (MG63). The 50% cell mortality was observed at 97.9 μg/ml and it proved less cytotoxicity effect with better biocompatibility. Thus, overall results showed that the nanocomposite as an efficient electrocatalyst towards hydrogen evolution reaction and targeted drug delivery applications.

High Performance Copper Based Metal Organic Framework for Removal of Heavy Metals From Wastewater

The biggest challenge of this century is the generation of wastewater which is released to the environment due to industrial expansion. Industrial development has caused the release of various pollutants including heavy metals such as Cd, Pb, and Cr into the environment. In this study, copper diphenylamine metal-organic framework (Cu-DPA MOF) has been synthesized via hydrothermal method and its adsorption capacity toward the removal of heavy metals from wastewater was examined. The removal efficiency of heavy metals by Cu-DPA MOF was tested at optimized adsorption parameters such as optimal adsorbent dosage, pH, initial metals concentration, and adsorption time. The heavy metals concentration in the wastewater before treated with the as-synthesized MOF was determined to be 0.3027, 0.0098, and 0.1021 mg/L for Cr, Cd, and Pb, respectively. The corresponding concentrations of heavy metals in wastewater were reduced to 0.0015, 0.00024, and 0.00016 mg/L when treated with the as-synthesized MOF. As a result, a maximum removal efficiency of 97.6%, 99.5%, and 99.5% was achieved for Cd, Cr, and Pb metals, respectively. This is possibly due to the high porous nature and huge surface area of the as-synthesized MOF. The adsorption data were best fitted with Freundlich isotherm throughout this study. The study sheds light on the design of adsorbents with high removal efficiency of pollutants found in the environment.

Copper-Based Metal-Organic Framework Overcomes Cancer Chemoresistance through Systemically Disrupting Dynamically Balanced Cellular Redox Homeostasis.

Chemodrug resistance is a major reason accounting for tumor recurrence. Given the mechanistic complexity of chemodrug resistance, molecular inhibitors and targeting drugs often fail to eliminate drug-resistant cancer cells, and sometimes even promote chemoresistance by activating alternative pathways. Here, by exploiting biochemical fragility of high-level but dynamically balanced cellular redox homeostasis in drug-resistant cancer cells, we design a nanosized copper/catechol-based metal-organic framework (CuHPT) that effectively disturbs this homeostasis tilting the balance toward oxidative stress. Within drug-resistant cells, CuHPT starts disassembly that is triggered by persistent consumption of cellular glutathione (GSH). CuHPT disassembly simultaneously releases two structural elements: catechol ligands and reductive copper ions (Cu+). Both of them cooperatively function to amplify the production of intracellular radical oxidative species (ROS) via auto-oxidation and Fenton-like reactions through exhausting GSH. By drastically heightening cellular oxidative stress, CuHPT exhibits selective and potent cytotoxicity to multiple drug-resistant cancer cells. Importantly, CuHPT effectively inhibits in vivo drug-resistant tumor growth and doubles the survival time of tumor-bearing mice. Thus, along with CuHPT's good biocompatibility, our biochemical, cell biological, preclinical animal model data provide compelling evidence supporting the notion that this copper-based MOF is a predesigned smart therapeutic against drug-resistant cancers through precisely deconstructing their redox homeostasis.

Over 11 kg m-2 h-1 Evaporation Rate Achieved by Cooling Metal-Organic Framework Foam with Pine Needle-Like Hierarchical Structures to Subambient Temperature.

Solar steam generation has become a hot research topic because of its great potential to alleviate the drinking water crisis without extra energy input. Although some efforts focusing on designing spatial geometry have been made to multiply the evaporation performances of up-to-date three-dimensional evaporators, they still have some shortcomings, such as low material and space utilization efficiencies, complex spatial geometry, energy loss due to the hot solar absorption surface, and salt crystallization due to inefficient water supply. Herein, a biomimetic copper-based metal-organic framework (Cu-Cu(OH)2-MOF) foam sheet with interconnected pores and pine needle-like hierarchical structures consisting of Cu(OH)2 nanowires and MOF nanowhiskers is fabricated. The pine needle-like hierarchical structures of Cu-Cu(OH)2-MOF foam contribute to absorbing solar energy and supplying sufficient water by trapping incident light and enhancing the capillary force, respectively. Inspired by drying clothes outside under solar irradiation, through exposing one end of the Cu-Cu(OH)2-MOF foam to air, the biface evaporator achieves a subambient evaporation surface temperature and an evaporation rate of up to 3.27 kg m-2 h-1 under only one sun illumination. Furthermore, when coupled with an air flow, the biface evaporator realizes an excellent evaporation rate of 11.58 kg m-2 h-1 with an energy efficiency of 160.07% even in seawater, ensuring its great application prospect to be used in drinking water production and seawater desalination.

Effect of amine type on acidic toxic gas adsorption at ambient conditions on modified CuBTC

Two amine-modified copper-based Metal Organic Frameworks (MOF (CuBTC)) of different surface chemical and textural features were synthesized and used as adsorbents of acidic toxic gases (NO2 and H2S) in both moist (71% relative humidity (R.H.)) and dry conditions. The initial and exhausted samples were characterized by nitrogen adsorption, powder X-ray diffraction, scanning electron microscopy, thermal gravimetric analysis and Fourier transform infrared spectroscopy. The addition of melamine prevented full growth of CuBTC crystals and resulted in amorphous-like particles with sizes less than 200 nm. The material was non-porous with a small surface area. When urea was used as an amine source, the resulting particles maintained the overall octahedral shape of the parent CuBTC MOF and the material was more porous than the parent MOF. While the urea-modified CuBTC sample performed well as an NO2 adsorbent in the presence of moisture, the reactivity of the melamine-modified sample and its physical properties provided a favorable environment for the removal of H2S. The incorporation of amines into the MOF structure also resulted in surface defects /open copper sites that favored the removal of toxic gases in dry conditions. The reactivity of the adsorbents with toxic gases was demonstrated by the changes in the adsorbent colors, in texture, and in surface chemistry (organic salts, complexes, sulfides and nitrates were formed).