Bimetallic Organic Framework Research Articles

One-pot preparation and the electrochemical properties of the composite of the NiCo bimetallic organic framework and carbon quantum dots

By adding carbon dots to NiCo-MOF to enhance its electrochemical properties and screening the materials synthesised from different carbon sources, the composites synthesised from isocitric acid as the carbon source had the best performance.

Reasonable construction of a bimetallic organic framework MIL-88B (Fe, Ni) nanoenzyme based on deep learning assisted doxycycline hydrochloride and methyloxytetracycline hydrochloride

The MIL-88B (Fe, Ni) colorimetric intelligent sensing platform can monitor the concentration of MET and DOX in real-time.

A label-free ratiometric fluorescent aptasensor based on a peroxidase-mimetic multifunctional ZrFe-MOF for the determination of tetrodotoxin.

A Fe/Zr bimetal-organic framework (ZrFe-MOF) is utilized to establish a ratiometric fluorescent aptasensor for the determination of tetrodotoxin (TTX). The multifunctional ZrFe-MOF possesses inherent fluorescence at 445nm wavelength, peroxidase-mimetic activity, and specific recognition and adsorption capabilities for aptamers, owing to its organic ligand, and Fe and Zr nodes. The peroxidation of o-phenylenediamine (OPD) substrate generates fluorescent 2,3-diaminophenazine (OPDox) at 555nm wavelength, thus quenching the inherent fluorescence of ZrFe-MOF because of the fluorescence resonance energy transfer (FRET) effect. TTX aptamers, which are absorbed on the material surface without immobilization or fluorescent labeling, inhibit the peroxidase-mimetic activity of ZrFe-MOF. It causes the decreased OPDox fluorescence at 555nm wavelength and the inverse restoration of ZrFe-MOF fluorescence at 445nm wavelength. With TTX, the aptamers specifically bind to TTX, triggering rigid complex release from ZrFe-MOF surface and reactivating its peroxidase-mimetic activity. Consequently, the two fluorescence signals exhibit opposite changes. Employing this ratiometric strategy, the determination of TTX is achieved with a detection limit of 0.027ng/mL and a linear range of 0.05-500ng/mL. This aptasensor also successfully determines TTX concentrations in puffer fish and clam samples, demonstrating its promising application for monitoring trace TTX in food safety.

Engineering Platelet Membrane-Coated Bimetallic MOFs as Biodegradable Nanozymes for Efficient Antibacterial Therapy.

Nanocatalytic-based wound therapeutics present a promising strategy for generating reactive oxygen species (ROS) to antipathogen to promote wound healing. However, the full clinical potential of these nanocatalysts is limited by their low reactivity, limited targeting ability, and poor biodegradability in the wound microenvironment. Herein, a bio-organic nanozyme is developed by encapsulating a FeZn-based bimetallic organic framework (MOF) (MIL-88B-Fe/Zn) in platelet membranes (PM@MIL-88B-Fe/Zn) for antimicrobial activity during wound healing. The introduction of Zn in MIL-88B-Fe/Zn modulates the electronic structure of Fe thus accelerating the catalytic kinetics of its peroxidase-like activity to catalytically generate powerful ROS. The platelet membrane coating of MOF innovatively enhanced the interaction between nanoparticles and the biological environment, further developing bacterial-targeted therapy with excellent antibacterial activity against both gram-positive and gram-negative bacteria. Furthermore, this nanozyme markedly suppressed the levels of inflammatory cytokines and promoted angiogenesis in vivo to effectively treat skin surface wounds and accelerate wound healing. PM@MIL-88B-Fe/Zn exhibited superior biodegradability, favourable metabolism and non-toxic accumulation, eliminating concerns regarding side effects from long-term exposure. The high catalytic reactivity, excellent targeting features, and biodegradability of these nanoenzymes developed in this study provide useful insights into the design and synthesis of nanocatalysts/nanozymes for practical biomedical applications.

Reduced graphene oxide membrane confined bimetallic organic framework boosts Fenton-like process to ultrafast contaminants degradation

Fenton-like processes generate reactive oxygen species (ROS) to achieve degradation of organic pollutants, however, practical water treatment processes suffer from low ROS utilization owing to its ultra-short lifetime and mass transfer limitations. To solve these problems, a nano-confined reaction space was designed to facilitate a fast mass transfer process for efficient removal of organic pollutants. Herein, the CuCo-based bimetallic organic framework (CuCo-MOF) was loaded in the water-transporting interlayer nanochannels of reduced graphene oxide (rGO) membrane. Membrane-confined CuCo-MOF with multiple exposed reaction sites activate peroxymonosulfate (PMS), generating ROS for ultrafast removal of oxytetracycline (OTC) at a water fluxes of 87.3 L·m−2·h−1. Notably, this membrane can continuously and stably degrade OTC (100 %) within 30 h. In addition, free radical capture experiments and EPR analysis indicated that the main ROS of the reaction system were singlet oxygen (1O2) and sulfate radical (SO4−). Based on Fukui index results and LC-MS analysis, reaction sites of OTC attacked by ROS were identified and it’s possible degradation pathways were proposed.

BIMMOF-derived ZnS/Co9S8 heterojunctions decorated hollow carbon nanospheres as advanced anode materials for lithium-ion batteries

Metal-organic frameworks (MOFs) offer significant advantages for constructing bimetallic sulfides as anode materials for lithium-ion batteries. However, the crystal structure of pure MOFs tends to collapse during ion insertion and detachment, resulting in somewhat limited electrochemical performance. Here, the crystal size of the bimetallic organic framework (BIMMOF) is reduced by in situ growth on hollow carbon spheres (HCS) by the solvothermal method. As a result, the well-dispersed BIMMOF-derived ZnS/Co9S8 heterojunction anode material was obtained with hollow carbon spheres as support. Due to the unique structure of ZnS/Co9S8@N-HCS with ultrafine size and the synergistic effect of Zn2+ and Co2+, this anode material has excellent electrochemical performance. Especially, it exhibits a capacity of 1595 mAh g−1 after 100 cycles at 100 mA g−1 and maintains a capacity of 1109 mAh g−1 after 1800 cycles at 2500 mA g−1. The remarkable lithium storage properties demonstrated by the ZnS/Co9S8 heterostructure provide inspiration for the wide adoption of this structural design strategy to improve the electrochemical performance of bimetallic sulfide anodes.

A portable sensor for glucose detection in Huangshui based on blossom-shaped bimetallic organic framework loaded with silver nanoparticles combined with machine learning.

In this work, we propose a blossom-like Ni, Co bimetallic metal-organic framework (NiCo-MOF) synthesized hydrothermally and decorated with silver nanoparticles (AgNPs) via chemical reduction for electrochemical enzyme-free glucose sensing. The NiCo-MOF nanostructures had large specific surface area and good sensing performance. The AgNPs enhanced the electrochemical performance of the MOF, resulting in excellent electrochemical activity. The sensor exhibited sensitivities of 1191.84 and 271.19 μA mM-1 cm-2 in the linear ranges of 0.005-1.125 and 1.525-5.325mM, respectively, with a detection limit of 2.3μM. The sensor was successfully applied for glucose determination in Huangshui (HS) using an artificial neural network as machine learning (ML) model. The R2 value near 1, low RMSE, and high RPD values of the proposed ML model demonstrate its excellent fitting and prediction performance. This will provide a fast and portable intelligent sensing analysis technology for the detection of glucose in HS.

Ni‐Co‐based bimetal organic framework as superior electrode material for hydrogen evolution reaction and supercapacitors

AbstractMetal‐organic frameworks (MOFs) possess several desirable properties, including a homogeneous crystal structure, variable porosity, high surface area, and a notable adsorption affinity, making them highly promising contenders for deployment as electrode materials in supercapacitors (SCs) and water electrolyzers, which are acknowledged for the ever‐increasing demand for instantaneous energy. Herein, we report the rationally assembled Ni‐Co‐based bimetallic MOF compounds using a glutaric acid as an organic ligand and low‐temperature hydrothermal treatment that surmounts the electrocatalytic and electrochemical charge storage activity in an alkaline medium. The NiCo‐MOF surpassed the hydrogen evolution reaction (HER) among other as‐synthesized materials, exhibiting the least overpotential of 182 mV at 10 mA/cm2 of current density, showed splendid kinetics with a turnover frequency of 2.86 s−1, and higher stability after 1000 HER cycles in 1 M KOH. Furthermore, NiCo‐MOF impetuses were employed for SC application and displayed the highest specific capacitance of 978 F/g than Ni‐MOF (706 F/g) and Co‐MOF (91 F/g) at 1 A/g of current density. Theoretical studies exhibited that the optimal electronic coupling and synergistic effect due to Ni‐Co sites enhances the overall electronic properties of NiCo‐MOF. Therefore, enhancing its electrochemical performance concerning water‐splitting and charge storage. This study showcases a novel approach for producing ultrathin and flexible bimetallic MOF‐based electrode material to enrich the performance in electrocatalytic HER and SCs.

Box-Behnken design optimization of bimetallic-organic frameworks for effective removal of tartrazine food dye from aqueous solutions

Lanthanum and tin-based hetero bimetallic organic frameworks (MOFs) in the form of stacked nanorods (La/Sn@MOF) exhibit promising capabilities in removing the yellow dye Tartrazine (E102) from aqueous solutions. Various techniques such as SEM, XRD, XPS, FTIR, and BET were employed to assess the adsorbent, revealing a significant surface area of 736.82 m2/g. The study thoroughly investigated the impact of pH, initial dye concentration, adsorbent dose, contact time, and temperature on the elimination of E102 dye. The clearance of tartrazine follows the Langmuir isotherm and pseudo-second-order kinetics, with a maximum adsorption capacity of 694.72 mg/g according to the Langmuir isotherm model. The pHzpc value of 6.41 suggests favorable adsorption of anionic dyes like E102 dye at pH levels below 6.4. The adsorption process was characterized by adsorption energy of 29.46 kJ/mol, indicating a chemisorption process. Thermodynamic analysis revealed that the adsorption processes were both endothermic and spontaneous, as evidenced by the negative values for ΔGo and positive values for ΔHo. La/Sn@MOF proved to be a straightforward and effective method for treating industrial wastewater, with the added benefit of being reusable for up to five cycles. Interaction between La/Sn@MOF and E102 dye was found to involve hydrogen bonding, pore filling, and π-π interactions, among other mechanisms. Optimization of the adsorption procedure was achieved using the Box-Behnken Design method (BBD).

Preparation and performance of FeCo bimetallic organic frameworks with super adsorption and excellent peroxymonosulfate activation for tetracycline removal

As bifunctional materials for adsorption and peroxymonosulfate (PMS) activation, iron − cobalt bimetallic organic frameworks (FeCo − MOF) were successfully fabricated via a facile method at room temperature, and characterized by XRD, SEM, TEM, XPS, TGA, BET and FTIR. Due to the high specific surface area and electrostatic interaction, FeCo − MOF showed excellent adsorption capacity. 30 mg of FeCo − MOF can adsorb 87.5 % of tetracycline (TC) in a 100 mL aqueous solution (70 mg/L). The adsorption data are well fitted by the Langmuir model and pseudo − second − order adsorption kinetics, indicating the TC capture probably was monolayer molecular adsorption and chemisorption. Meanwhile, FeCo − MOF/PMS had the outstanding catalytic activity for TC degradation via PMS activation. 10 mg of FeCo − MOF can remove 91 % of TC within 5 min in a 100 mL aqueous solution (20 mg/L) with PMS (0.1 mmol·L−1). Quenching experiments showed that •OH, SO4•−, O2•− and 1O2 all participate in the TC degradation. The effects of PMS concentration, pH value, reaction temperature on TC degradation were investigated. Although the coexisting inorganic anions and small molecule acids inhibited the catalytic performance of FeCo − MOF/PMS, the TC removal rates were still greater than 80 %, indicating the FeCo − MOF/PMS system has a strong anti − interference ability to complex water environments. In addition, the complete degradation of various pollutants, including TC, methylene orange (MO) and methyl blue (MB), and TC degradation in different water bodies confirmed the wide applicability of the FeCo − MOF/PMS system.

Different ligand functionalized bimetallic (Zr/Ce)UiO-66 as a support for immobilization of phosphotungstic acid with enhanced activity for the esterification of fatty acids

Different ligand functionalized bimetallic organic framework ((Zr/Ce)UiO-66-X (X = H, NO2, NH2 and (OH)2) solids-supported phosphotungstic acid (HPW) has been fabricated through a facile impregnation process, and used in the esterification of methanol with oleic acid (OA). The obtained composites were characterized by FTIR, XRD, NH3-TPD, SEM-EDS, N2 adsorption-desorption isotherm, TG, Py-FTIR, and XPS. The characterization analysis shows that the HPW/(Zr/Ce)UiO-66-NO2 composite possesses the proper catalytic features, such as the greatest number of both strong Brønsted and Lewis acid sites, wider pores, relatively high surface area, and the existence of synergistic catalytic effects between HPW and (Zr/Ce)UiO-66-NO2 framework. In the screening, the maximum OA conversion rate using (Zr/Ce)UiO-66-NO2, HPW/(Zr/Ce)UiO-66-NO2, HPW/(Zr/Ce)UiO-66, HPW/(Zr/Ce)UiO-66-NH2, HPW/(Zr/Ce)UiO-66-(OH)2 catalysts is 13.7%, 91.6%, 81.6%, 80.7%, and 72.6% at 110 °C for 3 h, respectively. Moreover, the HPW/(Zr/Ce)UiO-66-NO2 catalyst presents the better reusability over four cycles. Besides these, the HPW/(Zr/Ce)UiO-66-NO2 catalyzed esterification reaction is estimated to have an activation energy of 33.7 kJ/mol. This present study provides an effective route for realizing biofuel production on an industrial scale involving heteropolyacids/bimetallic MOFs synergistic catalysts.

Design and synthesis of hierarchical MnO–Fe3O4@C/expanded graphite composite for sensitive electrochemical detection of bisphenol A

Hierarchically nanostructured binary transition metal oxide-based materials with high conductivity and catalytic activity are quite attractive for the electrochemical quantitative detection of environmental pollutants due to their natural abundance, variable oxidation state, and excellent synergies between metal sites. Herein, a new hierarchical MnO–Fe3O4@C/expanded graphite (EG) composite is designed and synthesized through a simple and in situ annealing method with the utilization of bimetallic organic framework (FeMn-MOF)/EG precursor. The synthesized MnO–Fe3O4@C/EG composite possesses a unique hierarchical nanoarchitecture that small-sized bimetallic oxide nanoparticles of 10–40 nm completely encapsulated by amorphous carbon layers of 2–4 nm are uniformly distributed on the EG platform. This distinctive structure combines the advantages of high conductivity, excellent catalytic activity, and strong stability. Resultantly, when it is applied to monitor environmental endocrine disruptors, the sensor exhibits a significant catalytic effect on the electrochemical oxidation of bisphenol A (BPA), inducing an amplified response current. In addition, the sensor shows a wide linear range of 1–50 μM and 50–400 μM for the BPA monitor, giving a sensitivity of 5208.8 and 1641.9 μA mM−1 cm−2, respectively. This study offers a new approach to design hierarchical binary metal oxide-based sensing materials as well as to explore their electrochemical properties and applications for the determination of emerging contaminants.

Bimetallic nanoparticles preparation from metallic organic frameworks, characterization and its applications in reclamation of textile effluents

Abstract Herein bimetallic nanoparticles of Co–Mn were prepared using metal-organic framework (CoMn2 (C2O4)3·6H2O) as a starting material. Initially, the bimetallic organic frame work was prepared which was then subjected to pyrolysis to get the desired product. Techniques like scanning electron microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) were used to characterize the bimetallic nanoparticles. These analyses revealed that the Co–Mn nanoparticles consisted of finely distributed Mn and Co, along with O in the composites. XRD data confirmed the presence of nano-scale ranges and alloy formation between Co–Mn. The nanoparticles were employed as adsorbent for methyl violet adsorption, with optimized conditions found to be pH 9, temperature 333 K, adsorbents dosage of 0.01 g, and 30 min of contact time. The pseudo-second-order kinetic model best described the adsorption kinetics data whereas Langmuir isotherm exhibited the closest fit, with a maximum adsorption capacity of 625 mg/g at 333 K. Thermodynamic parameters indicated endothermic processes, with ΔH° = 15.155 kJ mol−1, and the process to be spontaneous with negative ΔG° values −0.303, −0.831, and −1.886 (kJ mol−1) at 293 K, 313 K, and 333 K, respectively. The ΔS° value of 52.76 J mol−1K−1 suggested increased disorder at the solid-solution interface during adsorption. The adsorbent could be effectively used in reclamation of dyes loaded water as alternative of activated carbon.

Preparation of nickel-doped iron-based bimetallic organic framework carbonized derivatives for heterogeneous catalytic hydrogen peroxide degradation of 4-NP

A nickel-doped iron-bimetallic organic framework carbon-derived material (Fe-Ni-MOF@C) was successfully constructed by microwave-pyrolysis and used as a new non-homogeneous Fenton-like catalyst for the catalytic degradation of p-nitrophenol (4-NP) by hydrogen peroxide (H2O2). Several characterization results such as SEM and XRD show that Fe-Ni-MOF@C is successfully synthesized and has porous, strong stability and magnetic properties. Fe-Ni-MOF@C materials exhibit excellent catalytic performance for the degradation over a wide temperature (15–45 °C) and pH (3.00–9.00). Complete removal of 4-NP (30 mg/L) was achieved in 30 min at 25 °C and pH = 3. The material properties can be restored by calcination. According to the radical burst experiments, electron paramagnetic resonance spectroscopy (EPR) combined with the characterization results, the radicals acting in the Fe-Ni-MOF@C/H2O2 system are mainly •OH and, to a lesser extent, •O2−. The synergistic effect between Fe and Ni species accelerates electron transfer and radical generation, which is the reason for the material's high catalytic performance. High-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) was used to analyze the main degradation products and pathways. This study demonstrates that bimetallic organic framework carbon-derived materials with synergistic effects have great application prospects as non-homogeneous Fenton-like catalysts in the field of H2O2 oxidation of organic pollutants.

Fabrication and mechanism of La/Al bimetallic organic frameworks for phosphate removal

Lanthanum (La) is constantly used in phosphorus removal due to its high affinity with phosphate. Herein, a novel La/Al bimetallic organic framework was developed to improve the usage efficiency of La species. The effects of metal ratio, pH value and competitive anions were investigated, through which the adsorption mechanism was further explained. Results showed that when the doped La:Al ratio was 1:3, the absorbent (La1Al3-BTC) achieved the most excellent adsorption capacity of 210.3 mg P·g−1 and usage efficiency (P/metal ratio = 1.09). La1Al3-BTC can adapt to the wide pH range and multitudinous coexisting ions in real water, and its adsorption process was in accordance with Langmuir and pseudo-second-order models. Surface morphology of materials transformed from rod-like crystal to amorphous structure as the increase of Al doping. La replaced some Al atoms and embedded in Al-BTC skeleton. The specific surface area raised from 9.27 m2·g−1 of La-BTC to 257.01 m2·g−1 of La1Al3-BTC. The main mechanism for the adsorption of phosphate was the inner-sphere complexation occurred in the La active sites. Electron migration between different metals enhanced the adsorption process. Density-function theory (DFT) calculation well matched the experimental phenomenon. Overall, the development of La1Al3-BTC presented new potential applications for enhanced phosphorus removal and provided new insights for the design of La-based adsorbents.

Co/Ni-MOF as a bifunctional electrode material for electrochemical sensor and oxygen evolution reaction

In recent years, the demand for economical multifunctional materials has increased significantly. In this paper, Co/Ni-based bimetallic-organic frameworks (Co/Ni-MOFs) materials were prepared, which showed good electrochemical recognition and oxygen evolution bifunctional activity in alkaline environment. The electrochemical test showed that the response time of the material to glucose was less than 3 s, the sensitivity was 2.0826 μAmM−1 cm−2, and the detection limit was 8.84 μM. The material also exhibits a good overpotential of 410 mV at a current density of 100 mA cm−2 and Tafel slope of 451 mV dec−1. The results show that Co/Ni-MOFs can be used as an electrocatalyst for electrochemical sensors and water splitting reactions.

A bimetallic organic framework based fluorescent aptamer probe for the detection of zearalenone in cereals

In this work, a bimetallic organic framework (Cu/UiO-66) based “turn on” fluorescent aptamer probe was designed for the high-efficiency detection of zearalenone (ZEN). In the probe, the 6-carboxyfluorescein-labeled aptamer (FAM-Apt) was used as the recognition element, and the electrostatic interaction, coordination effect, and photoinduced electron transfer effect between FAM-Apt and Cu/UiO-66 caused fluorescence quenching. When ZEN existed, FAM-Apt recognized ZEN specifically, causing FAM-Apt to separate from the surface of Cu/UiO-66 and recovery of fluorescence. Under the optimal conditions, the probe had a linear detection range of 0.5 ng/mL–60 ng/mL, and the detection limit was 0.048 ng/mL. The application potential of the probe was verified by real detection of various cereals and their products, with a standard recovery from 83.67 %–106.8 %. The development of this efficient, rapid, and sensitive ZEN detection method provides a new platform for the quality control of cereals and their products.

Fast and Sensitive Detection of CO by Bi-MOF-Derived Porous In2O3/Fe2O3 Core-Shell Nanotubes.

In2O3 is an optimal material for sensitive detection of carbon monoxide (CO) gas due to its low resistivity and high catalytic activity. Yet, the gas response dynamics between the CO gas molecules and the surface of In2O3 is limited by its solid structure, resulting in a weak gas response value and sluggish electron transport. Herein, we report a strategy to synthesize porous In2O3/Fe2O3 core-shell nanotubes derived from In/Fe bimetallic organic frameworks. The fabricated porous In2O3/Fe2O3-4 core-shell nanotubes present outstanding gas sensitivities, including a response value 3.8 times (33.7 to 200 ppm CO at 260 °C) higher than that of monometallic-derived In2O3 (8.7), ultrashort response and recovery times (23/76 s) to 200 ppm CO, low detection limit (1 ppm), promising selectivity, and long-term stability. The enhanced sensing mechanisms are clarified by the combination of experiment and first-principles calculations, showing that the synergetic strategy of higher adsorption energy, increased electrical conductivity, higher electron transfer numbers, and larger specific surface area of porous core-shell structures promotes the surface activity and charge transfer efficiency. The present work paves a way to tune gas-sensing materials with special morphologies for the development of high-performance CO sensors.

A novel bimetallic organic framework catalyst induced by dual-ligand for highly efficient oxygen evolution

With the continuous advancement of non-noble electrocatalysts, metal-organic frameworks (MOFs) are emerging as a promising substitute for noble metal nanomaterials in oxygen evolution reaction (OER) due to their larger pre-development and higher cost-effectiveness. However, there are still challenges in modifying the electronic structure of MOFs at the molecular level to enhance their activity of OER. Herein, bimetallic CoNi MOFs were utilized and modified with terephthalic acid (A) and 2, 5-dihydroxyterephthalic acid (B) (A2.5B-CoNi MOFs) through a straightforward hydrothermal method. By adjusting the ratio of A and B dual-ligand, the A2.5B-CoNi MOFs with the best ligand ratio exhibit significantly enhanced OER activity with an overpotential of only 300 mV at a current density of 10 mA cm−2, a low Tafel slope of 45.27 mV dec−1. In addition, A2.5B-CoNi MOFs also have better long-term stability than commercial RuO2. This study provides a research direction for the development of high-performance OER electrocatalysts based on dual-ligand MOFs.

In situ synthesis of self-supporting conductive CuCo-based bimetal organic framework for sensitive nonenzymatic glucose sensing in serum and beverage

Most MOFs are associated with the inherent defect of low conductivity, limiting their further application in electrochemical sensing. Herein, a self-supporting conductive CuCo-based bimetal organic framework with HHTP as the organic ligand was in situ synthesized on carbon cloth via a one-step hydrothermal method, namely CuCo-MOF/CC. Benefiting from the advantages of electrical conductivity and bimetallic synergies, CuCo-MOF/CC exhibited remarkable electrocatalytic performance toward glucose. Consequently, the prepared sensor demonstrated an outstanding sensitivity of 9317 μA mM−1 cm−2, a wide range of 0.25–2374.5 μM, a low determination limit (0.27 μM), and a rapid response time (1.6 s). The reproducibility, stability, and selectivity were also proved to be satisfactory. Furthermore, the remarkable feasibility of proposed sensor was confirmed in serum and beverages. With the convenience of the one-step hydrothermal method and portability of self-supporting electrode, CuCo-MOF/CC has emerged as a promising candidate for commercial glucose sensors.