Synthesis Of HKUST-1 Research Articles

Water-stable composite of HKUST-1 with its pyrolysis products for enhanced CO2 capture capacity

The composite adsorbent of HKUST-1 with its pyrolysis products has excellent water stability and CO 2 capture capacity. • Synthesis of HKUST-1 and its pyrolysis products to prepare a novel CO 2 adsorbent. • The BET and V total of HKUST-1/x increased significantly compared with pure HKUST-1. • HKUST-1/800 had the highest CO 2 capacity of 9.02 mmol·g -1 at 273 K and 1 bar. • The CO 2 /N 2 (15:85) selectivity of HKUST-1/800 was 106. • HKUST-1/800 still maintained excellent CO 2 adsorption amounts after soaking in water. Parent metal-organic framework (MOF), especially HKUST-1, is difficult to achieve both high CO 2 adsorption capacity and excellent water stability. We proposed an innovative strategy to prepare novel composites of HKUST-1/x (x, pyrolysis temperature=400, 600, 800 ℃) by the combination of parent HKUST-1 and its pyrolysis products. SEM, FT-IR and XRD characterization results verified the successful modification of the samples. The adsorption isotherm curves of N 2 and CO 2 showed that HKUST-1/800 had the highest specific surface area (1817 m 2 ·g -1 ), pore volume (0.802 cm 3 ·g -1 ) and CO 2 adsorption capacity (9.02 mmol·g -1 , at 273 K and 1 bar), which exhibited a significant enhancement effect. As well as, the CO 2 /N 2 (15:85) selectivity of HKUST-1/800 was 2.4 times higher than that of pure HKUST-1. In addition, the hydrophobicity and water stability of HKUST-1/800 were improved significantly. The water contact angle (WCA) of HKUST-1/800 reached 82.5°, 3.5 times higher than that of pure HKUST-1, and HKUST-1/800 retained most of the CO 2 adsorption capacity (5.46 and 4.31 mmol·g -1 ) after soaking in water for 1 and 5 days, respectively. However, HKUST-1 lost the majority of its adsorption capacity (retained only 0.91 and 0.74 mmol·g -1 ). The increase in the number of Cu sites and the formation of hydrophobic microenvironment on the surface were the reasons for its excellent adsorption capacity and water stability. Above of all, these hold a great potential for carbon capture applications in humid environments.

HNTs@HKUST-1 strengthened PAAm hydrogel for strain sensing and antibacterial application

Highly stretchable hydrogel shows great potential for wearable strain sensors. However, the rapid propagation of bacteria while using wearable sensors may threaten health. In this work, HNTs@HKUST-1 composites were prepared by the incorporation of halloysite nanotubes (HNTs) during the synthesis of HKUST-1. HNTs depressed the crystal growth of the HKUST-1, which leads to the 2D nanosheet morphology. HNTs@HKUST-1 serves as a reinforcing agent for polyacrylamide (PAAm) hydrogels, and PAAm-HNTs@HKUST-1 has high tensile strain properties (elongation at break of 912.5% and tensile strength of 22.4 kPa). The Cu2+ in HKUST-1 endows remarkable conductivity and excellent antibacterial properties to the composite. The composite hydrogels were then developed as human motion detection sensors with antibacterial property to prevent microbial infection, which show recyclability, high sensitivity, and fast responsiveness. So, they have great potential as flexible antibacterial materials to monitor movements of the human body in real-time.

Optimization of the use of mother liquor in the synthesis of HKUST-1 and their performance for removal of chromium (VI) in aqueous solutions

In this study, copper-benzene tricarboxylic (Cu-BTC), or better known as HKUST-1, was successfully synthesized using the solvothermal method in a solvent mixture of water, ethanol and N,N-Dimethylformamide (DMF). The mother liquor from the first synthesis was reused as a solvent for the subsequent HKUST-1 synthesis for up to four repetitions, cutting back the use of fresh solvent as much as 37 %. The fifth material obtained showed similar thermal stability and specific surface area to that of the first one, even though the surface morphology turned from an octahedral shape in the first material to an irregular shape in the fifth material. The results of the adsorption study on Cr(VI) in aqueous media showed that the first and the fifth materials had adsorption capacities of 91 mg/g and 100 mg/g respectively. Both adsorbents followed a pseudo-second order adsorption kinetics with a Langmuir isothermal adsorption model.

Synthesis of HKUST-1 with addition of Al-MCM-41 as adsorbent for removal of methylene blue from aqueous solution

HKUST-1 and Al-MCM-41/HKUST-1 composites were successfully synthesized by a solvothermal method in a mixture of N-N′-dimethylformamide (DMF), ethanol and water in a ratio of 1:1:1 at 100 °C for 10 h, with mass variations of Al-MCM-41 at 3, 5 and 7% toward the mass of HKUST-1, respectively. The results of the XRD analysis showed characteristic peaks of HKUST-1 at 2θ of 6.61, 9.39, 11.51 and 13.31° with high intensities. The addition of mesoporous aluminosilicate, Al-MCM-41, did not significantly alter the diffraction pattern except for the decrease in the intensity of the characteristic peaks. The FTIR spectra showed the presence of absorption bands typical of both HKUST-1 and Al-MCM-41 materials. HKUST-1 and Al-MCM-41/HKUST-1 composites showed exceptional performance in rapidly removing methylene blue at greater than 95% removal in less than 14 min. Isothermal and kinetic adsorption studies follow the modeling of the Freundlich isotherm and pseudo-second order kinetics.

The synthesis of HKUST-1/SiO2 composite material based on 3D printing

We use photosensitive resin as material, and adopt 3D printing and pyrolysis to prepare silica ceramics. HKUST-1 was grown on the ceramic surface by step-by-step in-situ growth method to obtain the HKUST-1/SiO2 composite material. The HKUST-1/SiO2 composite material was characterized by X-ray powder diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), thermogravimetric analysis (TG). The HKUST-1/SiO2 composite material not only has the characteristics of HKUST-1 and SiO2, but also can be designed into different complex shapes. In addition, the composite can be easy to separate from the product without centrifugation or filtration after the reaction is completed. The application of benzyl alcohol oxidation was an example to the performance of composite catalysts.

In situ growth of metal-organic framework HKUST-1 in an organic polymer as sorbent for nitrated and oxygenated polycyclic aromatic hydrocarbon in environmental water samples prior to quantitation by HPLC-UV.

An in situ preparation of metal-organic framework (HKUST-1) on the surface of an organic polymer is reported. The hybrid material was evaluated as sorbent for solid-phase extraction (SPE) of oxygenated and nitrated polycyclic aromatic hydrocarbons (PAHs). The growth of HKUST-1 on MAA-based polymer was accomplished using a layer-by-layer assembly strategy. The HKUST-1-polymer was characterized using powder X-ray diffraction and scanning electron microscopy to demonstrate the incorporation of MOF crystals onto the polymer surface. The MOF (nano)crystals were characterized using high-resolution transmission electron microscopy and high-angle annular-dark-field scanning transmission electron microscopy. The water-stable MOF-polymer was evaluated as SPE sorbent, and several variables that can influence the extraction recoveries of PAH derivatives were investigated. Under the selected conditions, the detection limits varied between 4 and 21ng·L-1, and the precision (relative standard deviation) was below 12%. The recovery values for spiked solutionsranged from 95 to 104%, and the enrichment factor achieved was close to 1000-fold using a high sample volume (100mL) and very low desorption volume (100μL). The SPE enrichment combined with HPLC and DAD detector was successfully applied to the extraction and determination of polycyclic hydrocarbons in environmental water samples. Graphical abstract A layer-by-layer synthesis of HKUST-1 onto polymer surface was performed and applied to isolation of PAH derivatives in environmental water samples.

Construction of planar-type defect-engineered metal–organic frameworks with both mixed-valence sites and copper-ion vacancies for photocatalysis

This manuscript presents a facile paradigm for controllably developing planar-type defect-engineered metal–organic frameworks (DEMOFs) by systematically doping reductive defect linker vanillin (VAN) during the synthesis of HKUST-1.

Synthesis of HKUST-1 and zeolite beta composites for deep desulfurization of model gasoline.

Composites of zeolite beta microspheres@nanosized HKUST-1 and micro-octahedron-shaped HKUST-1@nanosized zeolite beta were fabricated to remove thiophene from model oil. The two composite materials exhibited a higher adsorption capacity and faster adsorption rate than their corresponding mechanical mixture of HKUST-1 and zeolite beta when the sulfur concentration was at around 100 ppmw.

Direct in Situ Conversion of Metals into Metal-Organic Frameworks: A Strategy for the Rapid Growth of MOF Films on Metal Substrates.

The fabrication of metal-organic framework (MOF) films on conducting substrates has demonstrated great potential in applications such as electronic conduction and sensing. For these applications, direct contact of the film to the conducting substrate without a self-assembled monolayer (SAM) is a desired step that must be achieved prior to the use of MOF films. In this report, we propose an in situ strategy for the rapid one-step conversion of Cu metal into HKUST-1 films on conducting Cu substrates. The Cu substrate acts both as a conducting substrate and a source of Cu2+ ions during the synthesis of HKUST-1. This synthesis is possible because of the simultaneous reaction of an oxidizing agent and a deprotonating agent, in which the former agent dissolves the metal substrate to form Cu2+ ions while the latter agent deprotonates the ligand. Using this strategy, the HKUST-1 film could not only be rapidly synthesized within 5 min but also be directly attached to the Cu substrate. Based on microscopic studies, we propose a plausible mechanism for the growth reaction. Furthermore, we show the versatility of this in situ conversion methodology, applying it to ZIF-8, which comprises Zn2+ ions and imidazole-based ligands. Using an I2-filled HKUST-1 film, we further demonstrate that the direct contact of the MOF film to the conducting substrate makes the material more suitable for use as a sensor or electronic conductor.

Synthesis of HKUST-1#MCF compositing materials for CO2 adsorption

A series of compositing materials comprise HKUST-1 and siliceous mesocellular foam (MCF) was successfully fabricated following a one-pot method. The effect of MCF functionalization on the formation, structure properties, and performance in CO2 adsorption of the composting materials was investigated. All the composites were interestingly showing higher CO2 uptakes as compared with either the pure HKUST-1 or the MCF-x owing to the newly formed porous structures at the interface of the two components, the best performing sample, HK#MCF-NH2, exhibited a promising CO2 adsorption capacity of 3.89 mmol/g (25 °C, 1 bar) with excellent cyclic stability and selectivity over N2.

Elaboration of metal organic framework hybrid materials with hierarchical porosity by electrochemical deposition–dissolution

Rationally designed hierarchical macro-/microporous HKUST-1 electrodes were prepared via an electrochemical deposition–dissolution technique with the motivation to overcome diffusion limitations that typically occur for conventional microporous MOFs. A colloidal crystal of silica spheres was prepared by the Langmuir–Blodgett (LB) technique. Using this crystal as a template, macroporous copper electrodes with a controlled number of pore layers were prepared via electrodeposition. After the removal of the template, the synthesis of HKUST-1 was performed via partial anodic dissolution of the copper surface in the presence of an organic linker, leading to the deposition of HKUST-1 on the electrode surface with the designed macroporous structure. The macroporous Cu electrodes do not only behave as structural templates but are also the Cu source for the formation of MOFs. The applied potential and deposition time allow the characteristics of the porous layer to be fine-tuned. The developed synthesis is rapid, occurs under mild conditions and therefore opens up various potential applications including catalysis, separation and sensing based on these hierarchical materials.

The controlled regulation of morphology and size of HKUST-1 by “coordination modulation method”

Three types of modulators, including sodium formate, sodium acetate and triethylamine were used to tailor the morphology and size of HKUST-1 crystals by “coordination modulation method”. Through exploring the reaction parameters during the synthesis of HKUST-1, fascinating crystals morphologies, including hierarchical octahedral-shape crystals and nanocrystals were obtained by a solvothermal treatment. This paper discloses two essential functions of the modulator for the fabrication of uniform nanocrystals: Adjusting the proper acid–base environment of the reaction medium which governs the nucleation process and capping groups capable of inhibiting crystallites from growing. Moreover, samples were fully characterized by various techniques and the formation mechanism of the hierarchical octahedral-shape crystals was deduced.