Cadmium Metal Organic Framework Research Articles

Feasible synthesis and physicochemical features of a luminescent cadmium-metal organic frameworks (Cd-MOFs) composite, and its functionalization as a turn-off sensor towards selective determination of bisphenol A in food, water, and paper products

In the current study, a cadmium-metal organic frameworks (Cd-MOFs) structure was developed using a chemical process. The work comprised two main stages, initially inspection of the physicochemical features of the structure, and secondly, the application of the prepared Cd-MOFs as a turn-off nanosensor for the spectrofluorimetric determination of bisphenol A (BPA). Field emission scanning electron microscopy (FESEM) revealed the morphological features with the flake-like resembled shape. The elemental peaks for C, O, N, S, and Cd were residing as demonstrated by the energy-dispersive X-ray (EDX) results. The nonporous structure with a surface area of 25 cc/g was determined through the BET surface area results. The fluorescence spectra of Cd-MOFs demonstrated fluorescence emission at 470 nm after excitation at 320 nm. The quenching of the native fluorescence of Cd-MOFs was quantitatively and selectively produced by increasing concentrations of BPA. Therefore, Cd-MOFs have been applied as a turn-off nanosensor for the spectrofluorimetric determination of BPA, for the first time. The proposed approach validates linearity over the concentration range of 0.05–1.0 µg/mL with a detection limit of 0.01 µg/mL, signifying the method’s high sensitivity. Detection of low concentrations of BPA allowed for the real sample analysis in the food industries, including orange juice, tap water, infant feeding bottles, and food contact sheets. Moreover, The excellent eco-friendliness and greenness of the established approach were verified by employing the Analytical GREEnness (AGREE) and complementary Green Analytical Procedure Index (ComplexGAPI). The RGB 12 algorithm has functioned to prove the proposed method is greener, whiter, more sustainable, analytically effective, and less expensive than the reported ones. The proposed approach was validated according to ICH guidelines. This method presents a hopeful approach to quickly and accurately detect and quantify BPA in the food industry, which reinforces food safety and guards consumers’ health.

Cadmium(II) Metal-Organic Frameworks Based on Iodine-Substituted Terephthalic Acid Derivatives and 1,1'-(1,4-Butanediyl)-bis-imidazole

Two metal-organic frameworks based on Cd(II) and 2-iodo-(2-I-Bdc) and 2,5-diodo-(2,5-I-Bdc)terephthalate were obtained: {[Cd(2-I-Bdc)(Bbi)]} (I) and {[Cd2(2,5-I-Bdc)2(DMF)2(Bbi)]} (II) (Bbi = 1,1'-(1,4-butanediyl)bis(imidazole)). The structures of both complexes were established by X-ray diffraction (CCDC no. 2258217 (I) and 2257566 (II)).

Thiophene-Functionalized Cadmium(II)-Based Metal-Organic Frameworks for CO2 Adsorption with Gate-Opening Effect, Separation, and Catalytic Conversion.

Two new porous three-dimensional cadmium(II) metal-organic frameworks (MOFs) containing thiophene-appended carboxylate acid ligands, formulated as [Cd(L1)(4,4'-Bipy)]n.2n(DMF) (1) and [Cd(L2)(4,4'-Bipy)]n.2n(DMF) (2) [where L1 = 5-{(thiophen-2-ylmethyl)amino}isophthalate, L2 = 5-{(thiophen-3-ylmethyl)amino}isophthalate, 4,4'-Bipy = 4,4'-bipyridine, and DMF = N,N'-dimethylformamide] have been synthesized and structurally characterized. The gas adsorption analysis of the activated MOFs shows that they specifically capture CO2 (uptake amount 4.36 mmol/g under 1 bar at 195 K) over N2 and CH4. Moreover, both MOFs show a gate-opening-closing phenomenon, which features the S-shaped isotherms with impressive hysteretic desorption during the CO2 adsorption-desorption process at 195 K. Ideal adsorbed solution theory (IAST) calculations of these MOFs displayed that the obtained selectivity values for CO2/CH4 (50:50) and CO2/N2 (15:85) are approximately 8.6-23 and 93-565, respectively. Configurational bias Monte Carlo simulation was performed to understand the mechanism behind the better CO2 adsorption by these MOFs. Catalytic activity of the MOFs for the CO2 fixation reactions with different epoxides to form cyclic carbonates were tested. These MOFs demonstrated a significantly high conversion (94-99%) of epichlorohydrin to the corresponding cyclic carbonate within 8 h of reaction time at 1 bar of CO2 pressure, at 70 °C, and they can be reused up to five cycles without losing considerably their activity.

Cadmium(II) Metal-Organic Frameworks Based on Iodine-Substituted Terephthalic Acid Derivatives and 1,1'-(1,4-Butanediyl)-bis-imidazole

Cadmium(II) Metal-Organic Frameworks Based on Iodine-Substituted Terephthalic Acid Derivatives and 1,1'-(1,4-Butanediyl)-bis-imidazole

A novel Cadmium metal-organic framework with exceptional nonlinear optical properties: Unveiling anisotropic charge transport and optical limiting behavior

A novel non-centrosymmetric Cadmium Metal-Organic Framework (Cd-MOF) crystal with chemical formula CdC8N8H14O2S4 was synthesized and characterized. The band structure and optical limiting properties of the Cd-MOF were investigated using Band structure calculations and Optical limiting studies. The band structure analysis showed that the crystal displayed a larger, highly dispersive band, highlighting significant anisotropic n-channel charge carrier mobility. The optical limiting study demonstrated that the Cd-MOF exhibited Reverse Saturable Absorption (RSA) behaviour with an optical limiting threshold value of 1094 kW/cm2. The NLO behaviour of the Cd-MOF provides a promising potential for its application in NLO devices.

Amino-induced cadmium metal–organic framework based on thiazole ligand as a heterogeneous catalyst for the epoxidation of alkenes

Selective epoxidation of olefins is of high interest in the chemical industry due to the many applications of epoxides. This study reports on the synthesis of Cd-MOF, [Cd(DPTTZ)(5-AIP)] (IUST-1) (where DPTTZ = 2, 5-di (pyridine-4-yl) thiazolo [5, 4-d] thiazole, 5-AIP = 5-Aminoisophthalic acid), by a reflux method, which can be considered as a fast and simple process. The morphology and structure of the synthesized IUST-1 were determined by using FE-SEM (Field Emission Scanning Electron Microscopy), EDX (Energy Dispersive Analysis of X-ray), Mapping (Elemental Mapping), CHNS (Elemental analysis), XRD (X-Ray Diffraction), FT-IR (Fourier Transform Infrared), and TGA (Thermo Gravimetric Analysis). The epoxidation of cyclooctene was investigated using the activity of catalytic IUST-1. The results showed that in the presence of tert-butyl hydroperoxide and CCl4 in a 1:2 alkene/oxidant ratio, a high epoxide yield (99.8%) was obtained. In addition, IUST-1 can be easily separated by simple filtration and recycled five times successfully with a slight decrease in activity. This compound has some advantages such as high yield, short reaction time, and ease of reuse, which make it a suitable heterogeneous catalyst for the epoxidation of cyclooctene.

Cuprous oxide core-shell heterostructure facilely encapsulated by cadmium metal organic frameworks for enhanced photocatalytic hydrogen generation

Light absorption and separation of photo-generated electrons and holes are important to photocatalytic hydrogen evolution of a photocatalyst. Herein, a special metal organic framework (MOFs) was fabricated by encapsulating of 2-methylimidazole and cadmium nitrate on the silica coated cuprous oxide (Cu2O/SiO2/CdIF). The structure, morphology, composition, and valence state of the obtained materials were analyzed. It was demonstrated that the core-shell Cu2O/SiO2/CdIF heterostructure was achieved. Also, the photocatalytic activity and stability of H2 generation over the Cu2O/SiO2/CdIF nanocomposite were investigated. Interestingly, the Cu2O/SiO2/CdIF nanocomposite exhibited high activity which was hardly changed after five recycles. By means of Raman spectra, solid diffuse reflection UV–vis spectra, photoelectric response, and interfacial resistance, it was shown that higher light absorption, efficient charge separation and strong synergistic effect among the components in the heterostructure were responsible to the enhanced performance in the Cu2O/SiO2/CdIF nanocomposite.

Luminescent Cd coordination polymer based on thiazole as a dual-responsive chemosensor for 4-nitroaniline and CrO42− in water

A novel highly fluorescent cadmium metal–organic framework, [Cd (DPTTZ) (OBA)] (IUST-3), synthesized by using two linkers 2, 5-di (pyridine-4-yl) thiazolo [5, 4-d] thiazole (DPTTZ) and 4, 4′-oxybis (benzoic acid) (OBA) simultaneously, which exhibits a two-dimensional framework. The characteristics of this Cd-MOF were investigated by single-crystal X-ray diffraction, Fourier transform infrared spectroscopy, elemental analysis, powder X-ray diffraction, and thermogravimetry analysis. The IUST-3 exhibits excellent luminescence property and good stability in water. Luminescent experiments indicate that the IUST-3 has remarkable sensitivity and selectivity for the detection of 4-nitroaniline (4-NA), and CrO42− anion with KSV = 1.03 × 105 M-1 (4-NA) and KSV = 2.93 × 104 M-1 (CrO42−) and low limit of detection 0.52 µM (4-NA) and 1.37 µM (CrO42−). In addition, the possible fluorescence quenching mechanism was explored in this paper.

Ferric ion substitution renders cadmium metal-organic framework derivatives for modulated Li storage based on local oxidation active centers.

In this work, a novel anionic Cd-MOF ([(CH3)2NH2]n[Cd(HL)DMF]n·2nH2O·nDMF, H4L = 1,2,4,5-tetrakis[(4-carboxy)phenoxymethyl]benzene) was synthesized for the first time. As a precursor, it was utilized to obtain Fe@Cd-MOF crystals via the substitution of Fe3+ ions due to a negatively charged framework and free-coordinated carboxyl group. Fe3O4/Fe-embedded carbon-based materials (Fe@Cd-MOFD) were further constructed by deriving Fe@Cd-MOF at high temperatures. The derived Fe@Cd-MOFD showed a structure resembling a central city with metal redox centers embedded into a carbon matrix. The introduced Fe3+ ions formed a local nano-sized metal oxide upon annealing, and these derived carbon materials offered high electronic conductivity. These pushed Fe@Cd-MOFD to remarkable electrochemical performance with an initial discharge capacity of 1703.8 mA h g-1. This work offers new insights into the fabrication of novel MOF-derived iron oxide hybrids for lithium storage.

Stable Cd Metal-Organic Framework as a Multiresponsive Luminescent Biosensor for Rapid, Accurate, and Recyclable Detection of Hippuric Acid, Nucleoside Phosphates, and Fe3+ in Urine and Serum.

Detecting biomarkers associated with diseases has significant meaning for early prevention, diagnosis, and treatment of diseases. The development of luminescent biosensors for rapid and accurate detection in real urine and serum is urgently desired for human health monitoring. Herein, a luminescent cadmium metal-organic framework, {[Cd(L)(bpbix)]·x(solv)}n (1), was successfully prepared by using a urea-functionalized dicarboxylate ligand, 5-(3-(pyridin-4-yl)ureido)isophthalic acid (H2L), 4,4'-bis((1H-imidazol-1-yl)methyl)biphenyl (bpbix), and the Cd2+ ion. The structure of 1 presents a 2-fold interpenetrating three-dimensional pillared-layer framework. The complex 1 exhibits good stability in different-pH aqueous solutions and physiological fluids. Strikingly, the complex 1 shows quick response, high sensitivity, good anti-interference performance, and a recyclable ability for simultaneous sensing of hippuric acid (HA), nucleoside phosphates, and Fe3+ in water. More significantly, this sensor can realize the sensitive and accurate detection of HA, nucleoside phosphates, and Fe3+ in real urine and serum and meet the practical detection needs in clinical diagnosis. These results indicate that the complex 1 as a multiresponsive luminescent biosensor possesses great potential for practical detection of HA, nucleoside phosphates, and Fe3+ in biological samples.

A novel triazene-based cadmium metal–organic framework as a selective fluorescent sensor for Hg2+

A new cadmium metal–organic framework (Cd-MOF) has been synthesized by one-pot reaction between 5,5′-(triaz-1-ene-1,3-diyl)diisophthalic acid (H4TEDA) and cadmium acetate. Interestingly, the uncoordinated triazene groups locate in the channel of Cd-MOF. Moreover, the compound exhibits good luminescent property. Benefitting from the porosity, uncoordinated triazene group and luminescence property, Cd-MOF displays high selective response for Hg2+, which makes it as a potential sensor for detecting the toxic metal ions.

Proton conduction in two highly stable cadmium(II) metal-organic frameworks built by substituted imidazole dicarboxylates

Recently, the fabrication of metal-organic frameworks (MOFs) with high proton conductivity (σ) still attracts the attention of many researchers. Herein, a multifunctional organic ligand, 4-hydroxyphenyl-4,5-imidazole dicarboxylic acid (p-HOPhH3IDC) was adopted to solvothermally prepare two stable one-dimensional Cd(II) MOFs, {[Cd2(p-HOPhHIDC)2(phen)2]·H2O}n (1) (phen ​= ​1,10-phenanthroline), {[Cd2(p-HOPhHIDC)2(2,2′-bipy)2]·H2O}n (2) (2, 2′-bipy ​= ​2, 2′-bipyridine) in the presence of the N-containing ligands. Consequently, thermogravimetric analysis (TG), powder X-ray diffraction (PXRD), and scanning electron microscopy (SEM) determinations were employed to explore their structural stability. Importantly, their water-mediated proton conductivity demonstrated significant humidity- and temperature-dependence, increasing with the increase of both, and could attain the best value above 10−4 ​S ​cm−1 under 100 ​°C and 98% RH. The structural analyses along with the calculation of activation energy revealed that the rich H-bonded networks inside their frameworks are responsible for the higher proton conductivity. Finally, the proton-conducting mechanisms of the two MOFs were highlighted.

Proton Conduction in Two Highly Stable Cadmium(Ii) Metal-Organic Frameworks Built by Substituted Imidazole Dicarboxylates

Proton Conduction in Two Highly Stable Cadmium(Ii) Metal-Organic Frameworks Built by Substituted Imidazole Dicarboxylates

Ferric Ion Substitution Renders Cadmium Metal-Organic Framework Derivatives for the Modulated Li Storage Based on Local Oxidation Active Center

Ferric Ion Substitution Renders Cadmium Metal-Organic Framework Derivatives for the Modulated Li Storage Based on Local Oxidation Active Center

Selective and fast growth of CdS nanocrystals on zinc (II) metal–organic framework architectures for photoelectrochemical response and electrochemical immunosensor of foot-and-mouth disease virus

The integration of cadmium sulfide (CdS) and metal organic frameworks (MOFs) has shown promise in applications such as photocatalysis and sensing. Herein, a sensitive electrochemical immunosensor based on a room temperature, simple and fast aqueous synthetic strategy of in-situ selective growth nanocystalline CdS on zinc metal organic framework (CdS@Zn-MOF) is reported. We investigated the possibility of growth CdS on various MOFs, synthesizing by electrosynthesis or solution phase syntheses with different metal ions (e.g. Zn2+, Cu2+, Fe3+, Co2+, Zr4+) and organic ligands (e.g. 1,3,5-benzenetricarboxylic acid, 2-methylimidazole, 1,4-benzenedicarboxylic acid, 2-aminoterephthalic acid). This simple experiment process proved that CdS nanocrystalline can selectively grow on varied structures Zn-MOFs with different organic ligands. The synthesis, characterization and mechanisms involved in the formation of this composite material was explored carefully and thoroughly. The unique properties of this composite presented a promising photoelectrochemical and electrochemical applications. Therefore, a sensitive Zn-MOF-labeled amperometric immunosensor based on this strategy for the detection of foot-and-mouth disease virus (FMDV) was developed. The logarithm FMDV concentration was range from 0.5 fg mL−1 to 5 ng mL−1 with a low detection limit of 0.05 fg mL−1. Moreover, this proposed sensor with good selectivity, acceptable reproducibility, and stability was successfully applied to detect FMDV in actual blood sample. Furthermore, this method of growth the CdS nanocrystalline in situ on a Zn-MOF device structure or platform also provides a new horizon for future optoelectronic applications.

Selective CO2 capture and multiresponsive luminescent sensor in aqueous solutions of cadmium metal-organic framework based on trigonal rigid ligand

We report here a new fashioned cd-metal-organic framework (MOF) exhibiting a (5, 6)-connected 2-nodal net, [Cd3(LMe)(H2O)]·DMF·3H2O constituted by two different metal clusters and a trigonal rigid 6-connected ligand. The analytic reveal that complex is a 3D structure. Each (LMe)6− ligand is linked to five dinuclear SBUs, which forms a 2D lay, and Cd1 ions are linked by two different deprotonated carboxylates to construct a 3D porous framework. IAST manifested that the selectivity coefficients under 1 bar for the N2/CO2 (85: 15) and CH4/CO2 (50: 50) compounds were 86 and 6 at 273 K, respectively. Complex exhibited selectivity of CO2 relative to N2 and CH4 upon removal of solvates. Moreover, the complex caused emission quenching in the existence of Fe3+, MnO4− and CHCl3 organic solvent molecules. The multi-response fluorescence probe has lofty sensitivity and low limit of detection in the existence of Fe3+ and MnO4−. It thus appears that the Cd-MOF is not only a useful strategy for CO2 capture, but a fluorescent transducer for simultaneous exploration of organic solvent, metal ions and inorganic anions.

A new three-dimensional twofold interpenetrated cadmium(II) metal-organic framework: synthesis, structure and photoluminescence properties.

The design and synthesis of metal-organic frameworks (MOFs) have attracted much interest due to the aesthetics of their crystalline architectures and their potential applications as new functional materials. A new twofold interpenetrated three-dimensional (3D) MOF, namely, poly[[triaqua(μ4-(2R,2'R)-2,2'-{[1,4-phenylenebis(carbonyl)]bis(azanediyl)}dipropionato-κ7O1:O1,O1':O4:O4,O4',O4'')(μ3-(2R,2'R)-2,2'-{[1,4-phenylenebis(carbonyl)]bis(azanediyl)}dipropionato-κ3O1:O4:O4)dicadmium(II)] dihydrate], {[Cd2(C14H14N2O6)2(H2O)3]·2H2O}n, (I), has been synthesized by the reaction of Cd(CH3COO)2·2H2O with the synthesized ligand (2R,2'R)-2,2'-{[1,4-phenylenebis(carbonyl)]bis(azanediyl)}dipropionic acid (H2L). Single-crystal X-ray diffraction analysis reveals that the carboxylate groups from two crystallographically independent L2- dianions link the cadmium cations into a one-dimensional helical secondary building unit (SBU). The resulting SBUs are extended into a 3D metal-organic framework via the terephthalamide moiety of the ligand as a spacer. In the crystal, two independent MOFs interpenetrate each other, thus producing a twofold interpenetrated 3D architecture, which shows an unprecedented 2-nodal (7,9)-connected net with the point (Schläfli) symbol (37·46·58)(38·411·516·6). MOF (I) was further characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction and thermogravimetric analysis. The photoluminescence properties and UV-Vis absorption spectrum of (I) have also been investigated. The MOF exhibits enhanced fluorescence emission with a high photoluminescence quantum yield of 31.55% and a longer lifetime compared with free H2L.

High Proton Conductivity of a Cadmium Metal-Organic Framework Constructed from Pyrazolecarboxylate and Its Hybrid Membrane.

A new type of metal-organic framework, [Cd2(pdc)(H2O)(DMA)2]n (pdc = 3,5-pyrazoledicarboxylic acid; DMA = dimethylamine), named Cd-MOF, was synthesized and characterized. There are regular rectangular pore channels containing a large number of dimethylamine cations in the crystal structure. AC impedance test results show the proton conductivity of Cd-MOF reaches 1.15 × 10-3 S cm-1 at 363 K and 98% RH. In order for its application in fuel cells, the Cd-MOF was introduced into a sulfonated polyphenylene oxide matrix to prepare a hybrid membrane, and the proton conductivity of the hybrid membrane has a high value of 2.64 × 10-1 S cm-1 at 343 K and 98% RH, which is higher than those of most MOF polymer hybrid membranes. The proton conductivity of the hybrid membrane of the SPPO polymer still maintains a certain degree of stability in a wide temperature range. To the best of our knowledge, it is the first proton exchange membrane that combines pyrazolecarboxylate cadmium MOFs and an SPPO polymer with high proton conductivity and good stability. This research may help to further develop the application of MOFs in the field of proton exchange membrane fuel cells.

An amino-functionalized three-dimensional cadmium metal–organic framework: Synthesis, characterization and excellent fluorescence sensing of Fe3+

An amino-functionalized three-dimensional cadmium metal–organic framework, [Cd1.5(L)(DMF)]·2H2O (complex 1) L = H3TTCA-NH2 = 2′-amino-[1,1′:3′,1″-terphenyl]-4,4″,5′-tricarboxylic acid), is successfully synthesized under solvothermal conditions and structurally characterized. Interestingly, as a transition metal organic framework, the cadmium metal–organic framework exhibits favorable luminescence properties. In addition, the cadmium metal–organic framework reveals excellent selective and sensitive fluorescence sensing for the recognition of Fe3+ with high quenching efficiency ( Ksv = 3.340 × 103 M−1), demonstrating that the cadmium metal–organic framework can be used as a potential sensor for Fe3+.

A water stable Cd(II) metal-organic framework for sensing pollutants with a high selectivity

Water pollution is a serious environmental problem and is increasing the threat to public health. In the experiment, a cadmium metal organic framework (MOF) with high selectivity and stability and a low detection limit is used to detect Fe3+ and MnO4– ions in an aqueous solution. Luminescence spectra measurements show that Cd—MOF can selectively and sensitively detect MnO4– and Fe3+ ions in an aqueous solution with low detection limits of 0.08 μM and 2.1 μM, respectively.