Journal articles: 'Copper Copper Porous materials. Anion separation' – Grafiati (2024)

Abstract:

Incramute Cu-Mn alloys were dealloyed to remove Mn by selective electrolytic separation. The porous dealloyed specimens were compressed at 0.17-14 GPa, resulting in densities of 55-88% of the density of pure copper. Some porous copper specimens before compression were soaked in a mixture of monomer (MMA) and the initiator (AIBN), compressed, and then polymerized by heating. Young's moduli of both the dealloyed porous copper and its PMMA composite were found to decrease exponentially with porosity and volume fraction of PMMA, respectively. The apparent activation energy for damping of Cu-PMMA composite near the glass transition temperature of PMMA was found to increase with decreasing volume fraction of PMMA.

Abstract:

The physicochemical and mechanical properties of new alkaline anion-exchange membranes (AAEMs) based on chitosan (CS) and poly(vinyl alcohol) (PVA) polymers doped with unsupported copper nanoparticles (NPs) and copper exchanged over different porous materials were investigated regarding ion-exchange capacity (IEC), OH− conductivity, water uptake (WU), water vapor permeability (WVP), and thermal and mechanical resistance. The influence of the type of filler included in different morphologies and filler loading has been explored using copper exchanged materials such as the layered porous titanosilicate AM-4, layered stannosilicate UZAR-S3, and zeolites Y, MOR, and BEA. Compared to commercially available anion-exchange membranes, the best performing membranes in terms of WU, IEC, OH− conductivity and WVP in this study were those containing 10 wt % of Cu-AM-4 and Cu-UZAR-S3, although 10 wt % Cu-MOR provided better mechanical strength at close values of WVP and anion conductivity. It was also observed that when Cu was exchanged in a porous silicate matrix, its oxidation state was lower than when embedded as unsupported metal NPs. In addition, the statistical analysis of variance determined that the electrochemical properties of the membranes were noticeably affected by both the type and filler loading, and influenced also by the copper oxidation state and content in the membrane, but their hydrophilic properties were more affected by the polymers. The largest significant effects were noticed on the water sorption and transport properties, which gives scope for the design of AAEMs for electrochemical and water treatment applications.

Abstract:

Carbon aerogel (CA) has a rich porous structure, in which micropores and mesopores provide a huge specific surface area to form electric double layers. This property can be applied to the application of capacitive deionization (CDI). The adsorption effect of CA electrode on Cu2+ in an aqueous solution was explored for solving heavy metal water pollution. The CAs were synthesized by a sol-gel process using an atmospheric drying method. The structure of CAs was characterized by scanning in an electron microscope (SEM) and nitrogen adsorption/desorption techniques. The adsorption system was built using Cu2+ solution as the simulation of heavy metal pollution solution. The control variate method was used to investigate the effect of the anion species in copper solution, the molar ratio of resorcinol to catalyst (R/C) of CA, and the applied voltage and concentration of copper ion on the adsorption results.

Abstract:

This work is dedicated to preparation and research of copper-containing solid-state mixed oxides based on F-doped titanium dioxide. All materials were prepared by hydrolysis of titanium tetraisopropoxide. NH4F was used as F‑ions source. Copper was introduced to the system in two ways: by impregnation from its copper nitrate and directly in the process of titanium dioxide synthesis. Microstructure, phase composition and surface area were studied by transmission electron microscope (TEM), X-ray diffraction (XRD) and low temperature nitrogen adsorption respectively. All materials have nanostructured porous structure and the majority of them contain only one TiO2 phase – anatase. States of the elements were determined by X-ray photoelectron spectroscopy (XPS). Photoluminescence spectra (PL) show low intensity of photoluminescence for TiO2 and F-TiO2 samples and no photoluminescence for copper-containing samples. The absence of photoluminescence for copper-containing samples is associated with efficient charge transfer and separation.

Abstract:

This study describes the application of porphyrin-embedded porous organosilicate materials to the adsorption of ammonia gas. Organosilicate scaffolds were synthesized through a surfactant-templating process combined with a phase separation technique. The structure offers a macro-textured scaffold to facilitate flow through the sorbent material and provide enhanced access to the available surface area provided by a combination of micro- and mesopores distributed over a range of sizes. The materials were grafted post-synthesis to provide sites for covalent immobilization of porphyrins. These porphyrins were utilized for incorporation of metal sites into the organosilicate materials. The removal of ammonia was evaluated for a number of materials incorporating copper metalloporphyrins of varied structure at varied loading levels. Results have been compared to removal of ammonia by a carbon material. Copper deuteroporphyrin IX bis-ethylene glycol provided the strongest interactions with ammonia. High loading levels of this porphyrin within the sorbent structure showed increasing evidence of stacking and did not improve the performance of the material.

Abstract:

Porous silicon can be used as an insulating material in Si devices and as a membrane for ion or molecule separation. Its recently demonstrated photo- and electro-luminescence properties may find novel applications in optoelectronics. Porous silicon has a large internal surface, and, with its pores filled with conducting materials, can form a capacitor with a high charge storage capacity. Recently, thin metal films have been electroplated on porous silicon substrates. These films were then detached and used as condenser microphone diaphragms. Electroplated metal films can also provide electrical contacts to an electro-luminescent porous silicon structure. In this paper, we report our TEM study of a copper electroplating process. We found that in such a process copper preferentially deposits from the bottom of the pore tips upward and fills the entire length of each pore as well as the horizontal side branches.Anodization of silicon was performed in an aqueous HF solution to form a porous layer. Silicon substrates used in this experiment were n-type, (l00)-oriented wafers with a doping concentration of 1017 cm−3 and p-type, (l00)-oriented wafers with a doping concentration of 1019 cm-3.

Abstract:

Rapeseed cake biochar was produced by pyrolysis at 973.15 K for 2 h, in anoxic conditions. Porous structure, specific surface area and die composition of waste rapeseed cake were studied. The specific surface area of rapeseed cake biochar was 166.99 m2·g−1, which exceeded most other biochars reported, which made it an attractive material during wastewater treatment. The SEM study of the material demonstrated a large number of pores formed on the cell wall, with a pore volume Vp = 0.08 cm3·g−1. The results indicate lower aromaticity and increased polarity of the tested material. The observed H/C ratio of 0.29 is similar for activated carbons. Furthermore, sorption properties of the obtained carbon material in relation to copper(II), zinc(II) and arsenic(III) ions were also studied. Moreover, the impact of parameters such as: sorption time, temperature, adsorbate concentration, sorbent mass and solution pH on the efficiency of the adsorption process of the studied cations was also examined. Sorption studies revealed that the sorbent can be successfully used for the separation of Cu(II) and Zn(II) from technological wastewaters. Rapeseed cake biochar exhibits superior Cu(II) adsorption capacity (52.2 mg·g−1) with a short equilibrium time (6 h). The experimental data collected show a high selectivity of the obtained carbon material relative to copper(II) and zinc(II) ions in the presence of arsenic(III) ions.

Abstract:

A robust porous metal–organic framework with dual functionalities of open metal sites (OMSs) and O-rich Lewis basic sites (LBSs) has been designed and synthesized, and shows high CO₂ uptake and excellent selectivity for CO₂ over N₂ and CH₄.

Abstract:

Abstract A simple and selective separation and preconcentration method was developed for the determination of Cu(II) ions. This method is based on adsorption of Cu(II) ions from aqueous solution on a bis(3-aminopropyl)amine modified silica gel column and flame atomic absorption spectrometric determination after desorption. Various analytical parameters such as pH, type of eluent solution and its volume, flow rate of sample and eluent, and sample volume were optimized. Effects of some cation, anion, and transition metal ions on the recoveries of Cu(II) ions were also investigated. Cu(II) ions were quantitatively recovered at pH 6; 5.0 mL of 2 M HCl was used as the eluent. The preconcentration factor was found to be 150. The LOD was 0.12 μg/L for Cu(II). The accuracy of the method was confirmed by analysis of Tea Leaves (INCT-TL-1) and Fish Protein (DORM-3) certified reference materials. The optimized method was applied to various water and food samples for the determination of Cu(II).

Abstract:

Metal organic frameworks (MOFs) are one of those compounds which have drawn attention in various applications due to their several interesting properties like tunable shape, size, pore size, easy functionalization, high surface area, pore volume, etc. Metal organic frameworks due to their uniform structures, tunable porosity, wide variety and stability on various topology, geometry, dimension and chemical functions of the molecular network give a remarkable structural diversity in comparison to other porous materials. This enables scientists to handle numerous framework structures, porosity and functionality effectively. The unique structural architecture and tunable properties of MOF’s makes them an interesting hybrid material consisting of organic and inorganic materials. MOF can be randomly constructed like Lego bricks and superior in terms of versatility in comparisson to other porous materials. A number of MOFs containing a wide variety of metal e.g. zinc, copper, iron, aluminium, magnesium, chromium, zirconium, gadolinium, manganese are gaining rapid growth in commercial markets for gas storage, adsorption, separation and catalytic applications. This concise review emphasizes various synthetic methods e.g. solvothermal process, hydrothermal synthesis, electrochemical synthesis, microwave synthesis, sonochemical synthesis, mechanochemical synthesis, of metal organic framework developed in the last few decades. It also addresses various applications of metal organic framework e.g. hydrogen storage, gas adsorption, drug delivery systems and bioimaging agents, biocatalysts, biosensors, electrochemical sensors, etc. It also comments on various challenges and futuristic applications of metal organic frameworks in various field e.g. liquid wate management, gaseous waste management, sunlight assisted catalysis, water purification, building materials, electronic devices, battery technologies, targeted drug delivery, solar cells, etc. of science and technology in coming decades.

Abstract:

Self-assembly is the most powerful force for creating ordered supramolecular architectures from simple components under mild conditions. π···π stacking interactions have been widely explored in modern supramolecular chemistry as an attractive reversible noncovalent tool for the nondestructive fabrication of materials for different applications. Here, we report on the self-assembly of cytidine 5’-monophosphate (CMP) nucleotide and copper metal ions for the preparation of a rare nanoporous supramolecular metal-organic framework in water. π···π stacking interactions involving the aromatic groups of the ancillary 2,2’-bipyridine (bipy) ligands drive the self-assemblies of hexameric pseudo-amphiphilic [Cu6(bipy)6(CMP)2(µ-O)Br4]2+ units. Owing to the supramolecular geometric matching between the aromatic tails, a nanoporous crystalline phase with hydrophobic and hydrophilic chiral pores of 1.2 and 0.8 nanometers, respectively, was successfully synthesized. The encoded chiral information, contained on the enantiopure building blocks, is transferred to the final supramolecular structure, assembled in the very unusual topology 8T6. These kinds of materials, owing to chiral channels with chiral active sites from ribose moieties, where the enantioselective recognition can occur, are, in principle, good candidates to carry out efficient separation of enantiomers, better than traditional inorganic and organic porous materials.

Abstract:

AbstractWhen synthesizing copper compounds containing polymeric adsorbents, it was found that the two copper oxides, Cu2O and CuO, deposited in the skeleton of a strongly basic macroreticular anion exchanger (An) radically diminished the porosity of the obtained composites in relation to the host material. In order to investigate this phenomenon more closely, An/Cu2O and An/CuO (both based on the commercial anion exchanger Amberlite IRA900Cl), containing 8.6 and 8.2 wt% Cu, respectively, were subjected to scrutiny. The porous characteristics of the thermally dried and freeze-dried samples were determined using the N2 adsorption–desorption method and mercury intrusion porosimetry. The thermally dried samples lost their porosity and increased their bulk density in relation to the pure resin indicated a significant reduction in their volume. It was found that during drying, the grains shrank as much as the pores collapsed. The decay of the porous structure resulted from the surface morphology of the Cu2O and CuO particles and their tendency to agglomerate. Both freeze-dried samples retained the porous characteristics typical for macroporous anion exchangers. In contrast to the most popular hybrid ion exchangers containing hydrated polyvalent metal oxides (such FeOOH), An/Cu2O and An/CuO showed markedly strong volume contraction effect in relation to moisture content. Graphical abstract

Abstract:

Electrochemical sensing has gained attention owing to its easy analysis and highly efficient outputs. Metal-Organic Frameworks (MOF) derived Nanoporous Carbon (NC) are recently widely used in chemical separation and sensing applications due to its large surface area, thermal and mechanical stability. MOF contains organic linkers (Imidazole) as clusters and inorganic metal (Copper) in the nodes. Zeolitic Imidazole Frameworks (ZIF). In this current work, we deal with the synthesis and characterization of Copper ZIF materials. The synthesized materials were characterized using SEM, PXRD, XPS, TEM, and FTIR. To check the catalytic activity of the carbonised- ZIF, the Glassy Carbon Electrode (GCE) was modified. The modified GCE is used to find out its activity against various biomolecules, such as Dopamine, Ascorbic Acid, Uric Acid, etc. All the results will be analyzed, and the simultaneous detection of biomolecules will also be checked with the modified GCE.