Ni-based Metal-organic Framework Research Articles

Electrochemical sensing of dopamine using a Ni-based metal-organic framework modified electrode

A Ni-based metal-organic framework (Ni-MOF) modified electrode was fabricated for electrochemical detection of dopamine. The Ni-MOF was synthesized by ionothermal synthesis method using an ionic liquid as a template. The morphology and composition of the Ni-MOF were characterized by scanning electron microscope, X-ray diffraction, thermogravimetric analysis, and attenuated total reflection Fourier transform infrared spectroscopy. Electrochemical responses of the Ni-MOF modified electrode toward dopamine were performed using differential pulse voltammetry. The electrochemical sensing performance of the Ni-MOF modified electrode toward dopamine was improved by the introduction of ionic liquid with a wide linear range (0.2–100 μmol L−1), and a low detection limit (60 nmol L−1). Further studies indicated that the modified electrode exhibited great selectivity to dopamine in complex mixtures, and the Ni-MOF modified electrode also has excellent stability and reproducibility. Moreover, the analysis of real samples confirmed that the modified electrode has a certain reliability.

The in situ derivation of a NiFe-LDH ultra-thin layer on Ni-BDC nanosheets as a boosted electrocatalyst for the oxygen evolution reaction

A Ni-based metal organic framework (Ni-BDC) and subsequently derived NiFe-LDH were studied to overcome the defect of the low availability of active sites for the oxygen evolution reaction (OER) during the water splitting process.

Facile one-pot solvothermal preparation of two-dimensional Ni-based metal-organic framework microsheets as a high-performance supercapacitor material.

We report a facile one-pot solvothermal way to prepare two-dimensional Ni-based metal–organic framework microsheets (Ni-MOFms) using only Ni precursor and ligand without any surfactant. The Ni-MOFms exhibit good specific capacities (91.4 and 60.0 C g−1 at 2 and 10 A g−1, respectively) and long-term stability in 5000 cycles when used for a supercapacitor electrode.

Activated Ni-Based Metal-Organic Framework Catalyst with Well-Defined Structure for Electrosynthesis of Hydrogen Peroxide

Activated Ni-Based Metal-Organic Framework Catalyst with Well-Defined Structure for Electrosynthesis of Hydrogen Peroxide

Gold nanoparticle decorated rGO-encapsulated metal-organic framework composite sensor for the detection of dopamine

In this study, by encapsulation of reduced graphene oxide (rGO) into Ni-based metal–organic framework (Ni-MOF) structure, the composite rGO@Ni-MOF was first prepared. Then, gold nanoparticle (AuNP) decorated rGO@Ni-MOF (rGO@Ni-MOF/AuNP) were obtained through the electrodeposition. The morphology and structure of rGO@Ni-MOF/AuNP were characterized by SEM, FTIR, and XRD. The rGO@Ni-MOF/AuNP modified electrode was used for the detection of dopamine. Combining the catalysis from Ni-MOF and AuNP with the conductivity of rGO endowed rGO@Ni-MOF/AuNP with synergetic high catalytic activity to the electrochemical oxidation of dopamine. The developed modified electrode had a good linear relationship with dopamine in the concentration range of 0.5∼120 μM, and the detection limit was 0.33 μM (S/N = 3). Additionally, the potential interferents, electrode stability, reproducibility, and practical applications were also studied and satisfactory results were obtained.

A Ni-based metal-organic framework with super-high C3H8 uptake for adsorptive separation of light alkanes

The separation of C2H6 and C3H8 from CH4 is extremely important in the petrochemical industry, but the separation technology is dominated by an energy-intensive and cost-intensive process of cryogenic distillation. With lower energy consumption and cost investment, adsorptive separation technology shows great potential for the purification of natural gas. Here, we prepared a Ni-based metal-organic framework CTGU-15 and investigated its performance for the separation of light alkanes. Results show that CTGU-15 has super-high C3H8 uptake (12.13 mmol/g) and relatively low CH4 uptake (0.40 mmol/g) at 298 K and 100 kPa. The reason why CTGU-15 shows super-high C3H8 uptake was studied by comparing the pore textural properties of CTGU-15 and other benchmark adsorbents. Additionally, computational simulations were used to explore the nature of the interaction of the C3H8 gas within CTGU-15. The adsorption selectivities of C3H8/CH4 and C2H6/CH4 on CTGU-15 are 170.7 and 5.2, respectively. Breakthrough experiments show that CTGU-15 can achieve the adsorptive separation of CH4/C2H6/C3H8 mixtures. Importantly, CTGU-15 can maintain the stability of the framework after the heat treatment at <770 K, five adsorption-desorption cycles and exposure to 58% RH for 3 days. This work indicates that CTGU-15 is a promising adsorbent for CH4/C2H6/C3H8 separation.

Facile synthesis of novel carbon dots@metal organic framework composite for remarkable and highly sustained oxygen evolution reaction

Craving to search sources of energy is constantly compelling the mankind to find a source that is renewable or has enormous reservoirs and at the same time it poses no hazardous effect to mankind. Today’s energy deficient world has been seeking for an electrocatalyst which has a simple and facile synthesis strategy with marvellous catalytic performance and has outstandingly sustained stability for the highly lethargic Oxygen Evolution Reaction (OER). Here, a Ni-based mixed linker Metal Organic Framework (MOF) was synthesized using 1,3,5-benzenetricarboxylic acid (BTC) and 4,4`-bipyridine (bpy) as organic linkers. Carbon Dots (CDs) were incorporated into MOF during synthesis to impart synergistic effect to the as-synthesized composite. All the synthesized samples i.e CDs, MOF and CDs@MOF were characterized by various techniques to confirm the structural, compositional, morphological and textural analysis. The synthesized composite possessed rods like morphology with uniform distribution of CDs which offered superb stability for almost 40 hrs, large electrochemical active surface area (ECSA), least charge transfer resistance (Rct), high turnover frequency (TOF), reasonably low onset potential, low overpotential and a comparably low Tafel slope. The electrocatalyst owed its great catalytic efficiency and substantial stability due to the synergistic effect between CDs and MOF. This work is an effort to exploit the fabulous potential of MOF based nano-composite towards water splitting.

Nickel nanoparticle/carbon catalysts derived from a novel aqueous-synthesized metal-organic framework for nitroarene reduction

Carbon-supported, non-noble metal-based catalysts derived from metal-organic frameworks (MOFs) are attractive alternatives to noble metal-based systems, but typical syntheses of the starting MOFs are not desirable from an environmental and practical perspective (e.g., they rely on non-innocuous organic solvents and long reaction times). Here, we report the preparation of a Ni-based MOF in aqueous medium, at moderate temperature (95 °C) and in a short reaction time (<30 min), which was used as a sacrificial template to access a family of Ni nanoparticle/carbon hybrids that were then tested as catalysts in the reduction of 4-nitrophenol (4-NP). The MOF-derived hybrids exhibited a mesoporous texture, with specific surface areas between ∼250 and 450 m2 g−1 depending on the carbonization temperature applied to the MOF, as well as high Ni contents (between ∼36 and 57 wt%). Notwithstanding the latter, the metal was homogeneously distributed throughout the carbon matrix in the hybrid and was quite resistant to extensive agglomeration and sintering, even at temperatures as high as 1000 °C. With increasing carbonization temperature, the Ni component was seen to go through different crystal phases, i.e., Ni3C phase → Ni hexagonal close-packed phase → Ni face-centered cubic phase. The results of the catalytic tests suggested the former and latter phases to be the most active towards the reduction of 4-NP, with catalytic activity values as high as 0.039 mol4-NP molNi−1 min−1.

A novel, noble-metal-free core-shell structure Ni–P@C cocatalyst modified sulfur vacancy-rich ZnIn2S4 2D ultrathin sheets for visible light-driven photocatalytic hydrogen evolution

Accelerating the carrier transfer and increasing the effective reaction site on the surface of photocatalyst are important measures to improve the hydrogen production of composite photocatalyst. Herein, through simultaneous carbonization and phosphorization strategies, a Ni-based metal-organic frameworks (MOFs) derived method is presented to prepare a promising cost-effective Ni–P@C cocatalyst and couple with S-vacancy ZnIn2S4 (Vs-ZIS) for boosting photocatalytic activity. In this system, abundant S vacancies are induced to the surface of ZnIn2S4 ultrathin sheets (4 nm thickness) to capture photoinduced electrons, thus avoiding the recombination of carriers on the surface of ZnIn2S4. Furthermore, Ni–P is introduced to enhance the transfer of photogenerated electrons and increase the reaction site, and the synthesized Ni–P@C cocatalyst is developed to act as electronic container where the carbon framework with graphitic sp2 hybridized structures enables strong electronic interactions at the interface layer. The Ni–P@C/Vs-ZIS-2 photocatalyst exhibits a robust H2 evolution rate of 11,064 μmol g−1 h−1, higher than Vs-ZIS (1542 μmol g−1 h−1) and ZIS (398 μmol g−1 h−1), and the apparent quantum efficiency of Ni–P@C/Vs-ZIS-2 is 12.4%. This study uncovers the role of surface S-vacancy of the ultrathin two-dimensional catalyst ZnIn2S4 coupling with Ni–P@C cocatalyst in affecting electron transfer and reaction site, opening new opportunities for achieving efficient hydrogen production.

Multivariate optimization of high removal of lead(II) using an efficient synthesized Ni-based metal–organic framework adsorbent

Abstract A new metal–organic framework (MOF) with the chemical formula of [Ni2F2(4,4′-Bipy)2(H2O)2](VO3)2·8H2O was introduced to adsorb Pb(II) with the highest capacity. The sorbent was characterized by thermogravimetric analysis (TGA), infrared spectroscopy (FT-IR), field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX), and elemental analysis. The optimum conditions were obtained by a face-centered central composite design (FCCD) as follows: adsorbent dosage (m) = 1.2 mg, initial concentration of Pb(II) (C) = 390 mg·L−1, and pH = 5. According to the Langmuir model (R2 = 0.9999), the maximum monolayer uptake capacity of lead(II) is 2400.7 mg·g−1, which is the highest observed amount for lead(II) adsorption. Neither of the old adsorbents for lead(II) has the uptake capacity over 2000 mg·g−1. The model of pseudo-second-order describes well the process kinetics. The adsorption process of lead (II) is independent of temperature changes. This compound can adsorb lead (II) from tap water. In addition to introducing a new MOF with the highest uptake capacity for removal of Pb(II) that is the outright novelty of this study, the concurrent modeling of both the removal percent (R) and the uptake capacity (q) is another important advantage. Because it achieves the more economical and favorable optimum conditions in comparison with the single optimization of each response.

Nanoribbon Superstructures of Graphene Nanocages for Efficient Electrocatalytic Hydrogen Evolution

Two-dimensional carbon architectures are attracting tremendous interests for various promising applications due to their outstanding electronic and mechanical properties, although it is a great challenge to rationally devise facile and operative methodologies to engineer their structural traits owing to complex synthetic processes. Herein, for the first time, we fabricate two-dimensional carbon nanoribbons via direct thermal exfoliation of one-dimensional Ni-based metal-organic framework (MOF) nanorods, in which interconnected graphitic carbon nanocages are self-assembled into a belt-like superstructure with carbon-encapsulated Ni nanoparticles immobilized on the surface. Due to the unparalleled structural superiority, the MOF-derived carbon nanobelts exhibit excellent catalytic performances in electrocatalytic hydrogen evolution. Importantly, the practical synthetic strategy may trigger the rapid development of carbon-based superstructures in many frontier fields.

Defect-Engineered Nanostructured Ni/MOF-Derived Carbons for an Efficient Aqueous Battery-Type Energy Storage Device.

A Ni-based metal–organic framework (Ni-MOF) has been synthesized using a microwave-assisted strategy and converted to nanostructured Ni/MOF-derived mesoporous carbon (Ni/MOFDC) by carbonization and acid treatment (AT-Ni/MOFDC). The materials are well characterized with Raman, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and Brunauer–Emmett–Teller (BET), revealing that chemical etching confers on the AT-Ni/MOFDC-reduced average nanoparticle size (high surface area) and structural defects including oxygen vacancies. AT-Ni/MOFDC displays low series resistances and a higher specific capacity (Cs) of 199 mAh g–1 compared to Ni/MOFDC (92 mAh g–1). This study shows that the storage mechanism of the Ni-based electrode as a battery-type energy storage (BTES) system can be controlled by both non-faradic and faradic processes and dependent on the sweep rate or current density. AT-Ni/MOFDC reveals mixed contributions at different rates: 75.2% faradic and 24.8% non-faradic contributions at 5 mV s–1, and 34.1% faradic and 65.9% non-faradic at 50 mV s–1. The full BTES device was assembled with AT-Ni/MOFDC as the cathode and acetylene black (AB) as the anode. Compared to recent literature, the AT-Ni/MOFDC//AB BTES device exhibits high energy (33 Wh kg–1) and high power (983 W kg–1) with excellent cycling performance (about 88% capacity retention over 2000 cycles). This new finding opens a window of opportunity for the rational designing of next-generation energy storage devices, supercapatteries, that combine the characteristics of batteries (high energy) and supercapacitors (high power).

Conversion of MOF into carbon-coated NiSe2 yolk-shell microspheres as advanced battery-type electrodes

Construction and design of electrode materials with complex hollow structure are of great significance and challenging. Herein, uniform carbon modified NiSe2 yolk-shell spheres were constructed by a facile and effective strategy using Ni-based metal-organic framework as self-sacrificing template. In particular, the carbon shells pyrolysis from organic ligands can improve electron conductivity and mechanical stability. Therefore, the as-obtained NiSe2@C nanocomposites exhibit a high specific capacity of 730 C/g at 2 A/g and remarkable cycling stability of 94% capacity retention after 10,000 cycles. In addition, the faradic behavior also has been carefully studied, and the low conduct resistance between carbon and NiSe2 nanoparticles can promote electron transfer efficiency, and ideal porosity structure can effectively facilitate ion diffusion, contributing to the outstanding electrochemical performance. Moreover, the assembled hybrid supercapacitor can deliver high energy density of 48.6 Wh/kg at 1023 W/kg and excellent cycling performance of 90% capacity retention after 8000 cycles, demonstrating its promising potential in practical application.

NiO nanoparticles decorated hexagonal Nickel-based metal-organic framework: Self-template synthesis and its application in electrochemical energy storage

A one-pot solvothermal strategy and subsequent calcination were proposed for fabricating a composite of NiO nanoparticles on hexagonal Ni-based metal–organic framework (Ni-MOF) (Ni-MOF@NiO). The prepared NiO nanoparticles on the hexagonal Ni-MOF not only improves the electrical conductivity and increases redox active sites, but also prevents the agglomeration of NiO nanoparticles. In particular, highly dispersed and small-sized NiO nanoparticles on the hexagonal Ni-MOF facilitates the migration of electrolyte ions, and the pseudocapacitive performance is evaluated through electrochemical measurements. At 0.5 A g−1, the Ni-MOF@NiO composite shows a specific capacitance of up to 1192.7 F g−1 and a high capacity retention (93.23% over 5000 cycles) in 3 M KOH. Moreover, the Ni-MOF@NiO nanoparticles and activated carbon are assembled into aqueous devices with a maximum energy density of 62.2 Wh kg−1. These results indicate the potential of Ni-MOF@NiO composite as an electrode material for application in supercapacitors. Additionally, the method of synthesizing Ni-MOF@NiO in this study can be used to synthesize other MOF@metal oxide materials for electrochemical energy storage and other related applications.

Application of Ni-based metal-organic framework as heterogeneous catalyst for disulfide addition to acetylene

Several recent studies have shown unique adsorption activity of metal organic frameworks (MOFs) towards unsaturated hydrocarbons. In the current article, we explored the application of Ni-MOFs for S-functionalization of acetylene. We showed that Ni-MOF-74 catalyzed the reaction of disulfide addition to gaseous acetylene with excellent selectivity. The prime advantage of the proposed Ni-MOF-74 over other examined catalysts was its easy separation and recycling possibility. Moreover, it demonstrated no leaching of Ni species into the solution. The work was supplemented with a study on the catalyst behavior in the course of the reaction by using SEM, EDX, XRD, and FT-IR methods.

Polyacrylonitrile Nanofiber Membranes Modified with Ni-Based Conductive Metal Organic Frameworks for Air Filtration and Respiration Monitoring

We developed a nanofiber membrane that blocks particulate matters (PMs) and monitors respiration. The membrane was composed of polyacrylonitrile (PAN) nanofibers and was prepared by electrospinning...

Unveiling the real active sites of Ni based metal organic framework electrocatalysts for the oxygen evolution reaction

Pristine metal organic frames (MOFs) have emerged directly as the electrocatalysts for oxygen evolution reaction (OER). However, the OER performance needs further improvement and the real active sites remain exclusive. Herein, the effect of ligands on the performance of MOFs and the real active sites of each MOFs were explored. Specifically, three Ni based metal organic frames (Ni-MOFs) with different ligands including formic acid (FA), 1,4-benzenedicarboxylic acid (BDC) and 1,3,5-benzenetricarboxylic (BTC) were prepared by a solvothermal method. The morphology, specific surface area, porosity, wettability, electrochemically surface area (ECSA) of each Ni-MOFs were tested. However, none of them could be well correlated to the OER performance except the content of Ni(OH)2 on the surface from XPS test. Moreover, the OER performance of each Ni-MOF could be improved by cyclic voltammetry (CV) and chronopotentiometry (CP). The morphology and composition of each Ni-MOF before and after electrochemical activation further reveal the real active sites of three Ni-MOFs investigated here were Ni(OH)2. These results were expected to provide useful information for designing more excellent OER electrocatalysts based on MOFs.

A Simple Ni-based Metal-organic Framework as Catalyst for Dye-sensitized Photocatalytic H2 Evolution from Water Reduction.

Metal-organic frameworks (MOF) are recently developed coordination porous materials, and their unique structures are very conducive to catalytic reactions. In this paper, p-benzenedicarboxylic acid (PBA)-Ni2+ MOF materials (denoted as PBA-Ni-x, where x represents the initial ratio of PBA to Ni2+ ) were synthesized by a hydrothermal method and characterized by X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and N2 gas adsorption. H2 gas was produced using the synthesized MOF as a photocatalyst and Eosin Y as a photosensitizer. The dependence of the special surface area and thickness of the nanosheets of Ni-MOF on the initial ratio of PBA to Ni2+ (PBA/Ni2+ ) was investigated. The BET surface areas of PBA-Ni-1 PBA-Ni-2 and PBA-Ni-3 are 11.00, 24.61 and 13.04m2 g-1 , respectively. And the thicknesses of nanosheets are approximately 600-1000, 200-500 and 300-700nm. Among the three materials, PBA-Ni-2 has the thinnest sheet-like structure and largest surface area. Thus, it displays the highest H2 evolution rate of 20.0μmolh-1 . The noble-metal-free hydrogen production system is valuable for the application of MOF materials in photocatalytic water splitting.

Efficient Nonenzymatic Sensors Based on Ni-MOF Microspheres Decorated with Au Nanoparticles for Glucose Detection

Au nanoparticles were decorated on Ni-based metal–organic frameworks to improve their electrochemical performance for nonenzymatic glucose detection through a convenient and fast microwave-assisted process. Various techniques including scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy dispersive X-ray mapping and X-ray photoelectron spectroscopy were used to characterize the Au@Ni-BTC composites. The results revealed that Au nanoparticles were uniformly deposited on the Ni-BTC microspheres. The constructed Au@Ni-BTC sensors showed highly increased glucose detection performance with a wide linear range (5–7400 μM), high sensitivity (1447.1 μA mM−1 cm−2) and low detection limit (1.5 μM). Moreover, they also exhibited good selectivity and preferable feasibility for serum sample analysis. The improved glucose sensing performance may be due to the synergistic effects of Au nanoparticles and Ni-BTC, which facilitated faster charge transfer in the electrochemical process. The study of Au@Ni-BTC may also provide a promising material for constructing highly efficient nonenzymatic glucose sensors.

Shape-controlled synthesis of Ni-based metal-organic frameworks with albizia flower-like spheres@nanosheets structure for high performance supercapacitors

Metal organic frameworks (MOFs) are considered as very promising positive electrode materials for supercapacitors. To achieve good electrochemical performance, in this work, we report a mixed-ligand approach to prepare modified Ni-MOF by using trimesic acid (BTC) as the modulator to partially replace the terephthalic acid (PTA) ligands. The introduction of BTC can induce the formation of nanosheets with inserted albizia flower-like spheres, where the nanowires on the albizia flower-like spheres can provide rich redox reaction sites and the “spacer” spheres between the layers can hinder the aggregation of the 2D nanosheets to provide fast transport pathways. Moreover, adsorption simulation shows that the adsorption energy of OH− on the mixed organic ligands is increased after introducing the BTC ligands, which may improve the reversible redox reaction kinetics in the electrode materials. The as-obtained albizia flower-like spheres@nanosheets structured Ni-MOF with the optimized amount of BTC exhibits a high capacitance of 920 F g−1 at 1 A g−1, good rate capability of 61% at 20 A g−1, and an excellent cycling stability in 6 M KOH electrolyte. This work may provide helpful guidance for controlling the structure and surface property of MOFs to improve the electrochemical performance for supercapacitors.