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1.
J Colloid Interface Sci ; 677(Pt B): 872-881, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39173519

RESUMO

The highly selective conversion of CO2 into valuable C2H4 is a highly important but particularly challenging reaction. Herein, the metal-organic frameworks MOF-74(Cu) with infinite Cu(II)-O chains and Cu-BTC (BTC=benzene-1,3,5-tricarboxylate) with paddle-wheel binuclear Cu(II) clusters are used as precursors. These MOFs are reduced by NaBH4 to obtain Cu0/Cuδ+-based photocatalysts denoted as R-MOF-74(Cu) and R-Cu-BTC, respectively. Significantly, R-MOF-74(Cu) achieves a high selectivity of 90.2 % for C2H4 with a yield rate of 6.5 µmol g-1 within 5 h due to its high Cu+ content. To the best of our knowledge, this C2H4 product selectivity is a record high among all the photocatalysts reported so far for photocatalytic CO2 reduction. In contrast, R-Cu-BTC only forms CO as a product with a cumulative yield of 0.7 µmol g-1 within 5 h. Photoelectrochemical characterization and electron paramagnetic resonance results show that R-MOF-74(Cu) has low interfacial transfer resistance, high photogenerated electron separation efficiency, and excellent CO2 activation and water oxidation performance. In addition, in situ Fourier transform infrared spectroscopy is used to determine the possible reaction pathway from CO2 to C2H4 over R-MOF-74(Cu). This work demonstrates the great potential of MOF-derived photocatalysts for the conversion of CO2 into C2H4 and provides guidance for future photocatalyst development.

2.
J Colloid Interface Sci ; 677(Pt A): 1052-1068, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39134080

RESUMO

Levofloxacin (LVX) is difficult to be naturally degraded by microorganisms in water, and its residues in water will pose significant risks to human health and ecological environment. In this study, Bi12O17Cl2 was used as the main body, Bi12O17Cl2/GO/Co3O4 composite photocatalyst was prepared by pyrolysis of zeolitic imidazolate framework-67 (ZIF-67) combined with in-situ precipitation method and used to degrade LVX. A sequence of characterizations shows that addition of Co3O4 and graphene oxide (GO) increases the visible light response range, improves the separation efficiency of photogenerated electrons and holes (e--h+) of photocatalyst, and thus improves the degradation efficiency of LVX. Under the optimal reaction conditions, the LVX degradation rate of Bi12O17Cl2/1.5GO/7.5Co3O4 can reach 91.2 % at 120 min, and its reaction rate constant is the largest (0.0151 min-1), which is 2.17, 13.14 and 1.53 times that of Bi12O17Cl2, Co3O4 and Bi12O17Cl2/7.5Co3O4, respectively, showing better photocatalytic performance. Simultaneously, the recycling stability of Bi12O17Cl2/1.5GO/7.5Co3O4 was also verified. The capture experiments and electron EPR test results showed that superoxide radicals (•O2-) and photogenerated holes (h+) were the primary active substances in the reaction process. Finally, combined with HPLC-MS results, the photocatalytic degradation pathway of LVX was derived. This work will provide a theoretical basis for the design of Metal Organic Frameworks (MOFs)-derivative modified Bi12O17Cl2-based photocatalysts.

3.
Food Chem ; 462: 141026, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39216373

RESUMO

Quantitative monitoring of the concentrations of epigallocatechin gallate (EGCG) and cysteine (Cys) is of great significance for promoting human health. In this study, iron/aluminum bimetallic MOF material MIL-53 (Fe, Al) was rapidly prepared under room temperature using a co-precipitation method, followed by investigating the peroxidase-like (POD-like) activity of MIL-53(Fe, Al) using 3,3',5,5'-tetramethylbenzidine (TMB) as a chromogenic substrate. The results showed that the Michaelis -Menten constants of TMB and H2O2 as substrates were 0.167 mM and 0.108 mM, respectively. A colorimetric sensing platform for detecting EGCG and Cys was developed and successfully applied for analysis and quantitative detection using a smartphone. The linear detection range for EGCG was 15∼80 µM (R2=0.994) and for Cys was 7∼95 µM (R2=0.998). The limits of detection (LOD) were 0.719 µM and 0.363 µM for EGCG and Cys, respectively. This work provides a new and cost-effective approach for the real-time analysis of catechins and amino acids.


Assuntos
Antioxidantes , Técnicas Biossensoriais , Catequina , Colorimetria , Smartphone , Colorimetria/métodos , Colorimetria/instrumentação , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Antioxidantes/análise , Antioxidantes/química , Catequina/análise , Catequina/análogos & derivados , Catequina/química , Cisteína/análise , Cisteína/análogos & derivados , Limite de Detecção , Análise de Alimentos/métodos , Análise de Alimentos/instrumentação
4.
Colloids Surf B Biointerfaces ; 245: 114294, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39368425

RESUMO

Immobilization of free enzymes facilitates their recovery and reuse, while also enhances their enzymatic characteristics. Hierarchically porous metal-organic frameworks (HP-MOFs) are promising candidates for enzyme immobilization. However, fabrication of HP-MOFs with more kinds of components as ligands is still a challenge. Herein, ultrastable crystalline MOFs with micro-, meso- and macroporous structure were constructed using guanosine 5'-monophosphate (GMP) as organic ligand through templated emulsification method. HP-MOFs crystals with the near rhomb-like, rod-like and slab-like morphology were interestingly obtained from Zn2+, Cu2+ and Cd2+ respectively. The HP-MOFs immobilized enzymes exhibited an enhanced enzymatic activity and stability. In addition, the immobilized CALB (Candida antarctica lipase B) showed great glycerolysis and esterification performances for glycerides preparation, with diacylglycerols (DAG) content over 60 wt% and triacylglycerols (TAG) content over 90 wt% obtained respectively from glycerolysis and esterification. Moreover, it retained 82.32 % of its initial glycerolysis activity after six cycles of reuse in glycerolysis. The present study will provide clues and show new horizons to explore new organic ligands for HP-MOFs fabrication, as well as to expand the applications of HP-MOFs and their supported enzymes.

5.
Chem Asian J ; : e202400896, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39384549

RESUMO

Nanoscale framework materials have received much attention due to their diverse morphologies as well as good properties, and synthetic methods to construct different dimensions have been reported. Therefore, the study of the relationship between different sizes, dimensions and properties has become a hot research topic. This article provides a comprehensive examination of the controllable synthesis strategies of nano-metal-organic frameworks (nano-MOFs) and nano-covalent-organic frameworks (nano-COFs) and their applications in energy storage and catalysis. Commences with an overview of the synthetic evolution of nanoscale framework materials, which have garnered attention due to their exceptional specific surface area, regular pores, and tunable structural functionality. Various preparation methods for 0D, 1D, 2D and 3D nanostructures are then highlighted. These synthesis strategies not only improve the stability and activity of the materials, but also provide a basis for the design of novel energy storage and catalytic materials. Furthermore, the article presents an overview of the recent advancements in the field of energy storage and catalysis, with a particular focus on the applications of nano-MOFs/COFs in zinc-, lithium-, and sodium-based batteries as well as supercapacitors. ​.

6.
Angew Chem Int Ed Engl ; : e202417435, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39385458

RESUMO

Photocatalytic reduction of diluted CO2 from anthropogenic sources holds tremendous potential for achieving carbon neutrality, while the huge barrier to forming *COOH key intermediate considerably limits catalytic effectiveness. Herein, via coordination engineering of atomically scattered Ni sites in conductive metal-organic frameworks (CMOFs), we propose a facile strategy for tailoring the d­band center of metal active sites towards high-efficiency photoreduction of diluted CO2. Under visible-light irradiation in pure CO2, CMOFs with Ni-O4 sites (Ni-O4 CMOFs) exhibits an outstanding rate for CO generation of 13.3 µmol h-1 with a selectivity of 94.5%, which is almost double that of its isostructural counterpart with traditional Ni-N4 sites (Ni-N4 CMOFs), outperforming most reported systems under comparable conditions. Interestingly, in simulated flue gas, the CO selectivity of Ni-N4 CMOFs decreases significantly while that of Ni-O4 CMOFs is mostly unchanged, signifying the supremacy for Ni-O4 CMOFs in leveraging anthropogenic diluted CO2. In-situ spectroscopy and density functional theory (DFT) investigations demonstrate that O coordination can move the center of the Ni sites' d-band closer to the Fermi level, benefiting the generation of *COOH key intermediate as well as the desorption of *CO and hence leading to significantly boosted activity and selectivity for CO2-to-CO photoreduction.

7.
Small ; : e2402486, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39380355

RESUMO

Precise control of the void environment, achieved through multiple functional groups and enhanced by structural adaptations to guest molecules, stands at the forefront of scientific inquiry. Flexible multivariate open framework materials (OFMs), including covalent organic frameworks and metal-organic frameworks, meet these criteria and are expected to play a crucial role in gas storage and separation, pollutant removal, and catalysis. Nevertheless, there is a notable lack of critical evaluation of achievements in their chemistry and future prospects for their development or implementation. To provide a comprehensive historical context, the initial discussion explores into the realm of "classical" flexible OFMs, where their origin, various modes of flexibility, similarities to proteins, advanced tuning methods, and recent applications are explored. Subsequently, multivariate flexible materials, the methodologies involved in their synthesis, and horizons of their application are focussed. Furthermore, the reader to the concept of spatial distribution is introduced, providing a brief overview of the latest reports that have contributed to its elucidation. In summary, the critical review not only explores the landscape of multivariate flexible materials but also sheds light on the obstacles that the scientific community must overcome to fully unlock the potential of this fascinating field.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 326: 125188, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39374560

RESUMO

How to achieve good dispersion of MOFs (metal-organic frameworks) is the key to its application in many fields. In our work, a novel MOF nanocomposite TBAPy-Yb was synthesized by solvothermal approach with TBAPy [1,3,6,8-tetrakis(p-benzoic acid)pyrene)] as the organic ligand and lanthanide metal ions as the metal ion source. Due to the coordination between phosphate and TBAPy-Yb, TBAPy-Yb had excellent dispersion in phosphate buffer and induced strong fluorescence emission in 435 nm. Gsp (gossypol) could regularly and instantly quench the induced fluorescence of TBAPy-Yb in the range of 10.0 to 70.0 µM and cause an obvious color change from blue to colorless. The detection limit was as low as 4.57 µM. The possible interferences in cottonseed oil did not influence the detection. The proposed method was effectively applied toanalyzeGsp oil with a recovery rate ranging from 94.20 % to 104.90 %. Furthermore, a portable and smart sensing platform was developed based on probe fixation and mobile phones.

9.
Chem Asian J ; : e202400990, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375850

RESUMO

Metal-organic frameworks (MOFs) are considered as an ideal enzyme support because of their porous structural superiority. However, MOFs@enzyme composites have usually compromised their hydrolysis efficiency due to the narrow space inducing unfavourable enzyme conformations. Herein, a thermo-responsive poly(N,N-dimethylacrylamide) (PD) was fixed onto the surface of UiO-66-NH2 (UiO) through a post-synthetic modification protocol. Using poly(2-vinyl-4,4 dimethylazlactone) (V) as a linker, PVD-UiO@cellulase composites were fabricated after cellulase was immobilized onto the UiO surface through covalent bonding. The composites conferred favorable cellulose conformations, boosting hydrolysis efficiency and stability, which relied on the soft PVD shell and confinement effect yielded by the curled PVD chains at high temperatures. Compared with free cellulase, the proposed composites exhibited a 33.1-fold enhancement of the Kcat values at 50 °C. The PVD-UiO@cellulase composites were applied to the hydrolysis of cellulose in the stalks and leaves of Epipremnum aureum. The results highlight the potential of smart PVD-UiO@cellulase composites in the hydrolysis of cellulose, affording a valuable platform for the preparation of unique MOFs@enzyme composites and their industrial applications.

10.
Artigo em Inglês | MEDLINE | ID: mdl-39356201

RESUMO

A machine learning (ML) model is developed for predicting useable methane (CH4) capacities in metal-organic frameworks (MOFs). The model applies to a wide variety of MOFs, including those with and without open metal sites, and predicts capacities for multiple pressure swing conditions. Despite its wider applicability, the model requires only 5 measurable structural features as input, yet achieves accuracies that surpass less-general models. Application of the model to a database of more than a million hypothetical MOFs identified several hundred whose capacities surpass that of the benchmark MOF, UMCM-152. Guided by the computational predictions, one of the promising candidates, UMCM-153, was synthesized and demonstrated to achieve superior volumetric capacity for CH4. Feature importance analyses reveal that pore volume and gravimetric surface area are the most important features for predicting CH4 capacity in MOFs. Finally, a reverse ML model is demonstrated. This model predicts the set of elementary MOF structural properties needed to achieve a desired CH4 capacity for a prescribed operating condition.

11.
Small ; : e2407747, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39370579

RESUMO

The heterogeneous and dynamic microenvironment of biofilms complicates bacterial infection treatment. Nanozyme catalytic therapy has recently been promising in treating biofilm infections. However, active nanozymes designed with the required precision targeting the biofilm microenvironment are lacking. This work proposes a spatiotemporally guided single-atom bionanozyme (BioSAzyme) for targeted antibiofilm therapy based on protein engineering of copper single-atom nanozyme (Cu SAzyme). The Cu SAzyme, synthesized via a novel mechanochemistry-assisted method, features highly accessible Cu-N4 active sites exposed on 2D N-doped carbon, exhibiting excellent triple enzyme-like activities according to experimental results and density functional theory calculations. Inheriting biofunctionality from both glucose oxidase and concanavalin A, BioSAzyme can localize the biofilm glycocalyx and catalyze endogenous glucose into H2O2 and gluconic acid, thus triggering multiplex cascade reactions with pH self-adaption to consume glucose and glutathione and generate •OH radicals. This spatiotemporally guided bionanocatalytic agent effectively inhibits E. coli O157: H7 and methicillin-resistant S. aureus biofilms in vitro and in vivo. Taking together, this work opens up new avenues for the rational design of single-atom nanozymes for precise antibiofilm therapy.

12.
Adv Mater ; : e2410067, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39374006

RESUMO

Photochromic materials with properties that can be dynamically tailored as a function of external stimuli are a rapidly expanding field driven by applications in areas ranging from molecular computing, nanotechnology, or photopharmacology to programable heterogeneous catalysis. Challenges arise, however, when translating the rapid, solution-like response of stimuli-responsive moieties to solid-state materials due to the intermolecular interactions imposed through close molecular packing in bulk solids. As a result, the integration of photochromic compounds into synthetically programable porous matrices, such as metal-organic frameworks (MOFs), has come to the forefront as an emerging strategy for photochromic material development. This review highlights how the core principles of reticular chemistry (on the example of MOFs) play a critical role in the photochromic material performance, surpassing the limitations previously observed in solution or solid state. The symbiotic relationship between photoresponsive compounds and porous frameworks with a focus on how reticular synthesis creates avenues toward tailorable photoisomerization kinetics, directional energy and charge transfer, switchable gas sorption, and synergistic chromophore communication is discussed. This review not only focuses on the recent cutting-edge advancements in photochromic material development, but also highlights novel, vital-to-pursue pathways for multifaceted functional materials in the realms of energy, technology, and biomedicine.

13.
J Fluoresc ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39320630

RESUMO

The hydrothermal method was employed to synthesize a novel bi-ligands LnMOF: Ln(cpioa)phen. The secondary ligand 1, 10-phen serves as a bridging agent to further facilitate energy transfer between Ln ions and the primary ligand H3cpioa. A comparison between Ln(cpioa) MOFs (Ln: Tb3+, Eu3+) and Ln(cpioa)phen MOFs (Ln: Tb3+, Eu3+) reveals that addition of the secondary ligand significantly improves the emission intensity by as high as almost 34 times. After detailed structural study, it is found that different Ln ions have the similar coordination in the Ln(cpioa)phen MOF. In addition, the chromaticity of Ln(cpioa)phen MOFs can be easily tuned by the amounts of doping Ln ions. La0.974Tb0.0255Eu0.0005(cpioa)phen MOF has a white emission with a CIE coordinate of (0.323, 0.343). Characterizations of corresponding LED devices show that device based on Ln(cpioa)phen MOF has better photoluminescence performances, which indicates that Ln(cpioa)phen MOF has great potential of for WLED applications.

14.
Molecules ; 29(18)2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39339312

RESUMO

The growing presence of diverse pollutants, including heavy metals, organic compounds, pharmaceuticals, and emerging contaminants, poses significant environmental and health risks. Traditional methods for pollutant removal often face limitations in efficiency, selectivity, and sustainability. This review provides a comprehensive analysis of recent advancements in innovative adsorbents designed to address these challenges. It explores a wide array of non-conventional adsorbent materials, such as nanocellulose, metal-organic frameworks (MOFs), graphene-based composites, and biochar, emphasizing their sources, structural characteristics, and unique adsorption mechanisms. The review discusses adsorption processes, including the basic principles, kinetics, isotherms, and the factors influencing adsorption efficiency. It highlights the superior performance of these materials in removing specific pollutants across various environmental settings. The practical applications of these adsorbents are further explored through case studies in industrial settings, pilot studies, and field trials, showcasing their real-world effectiveness. Additionally, the review critically examines the economic considerations, technical challenges, and environmental impacts associated with these adsorbents, offering a balanced perspective on their viability and sustainability. The conclusion emphasizes future research directions, focusing on the development of scalable production methods, enhanced material stability, and sustainable regeneration techniques. This comprehensive assessment underscores the transformative potential of innovative adsorbents in pollutant remediation and their critical role in advancing environmental protection.

15.
Molecules ; 29(18)2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39339472

RESUMO

The Zn/Cr-MOFs/TiO2 composites were synthesized using the solvothermal method. XRD, FTIR, and SEM techniques were utilized to characterize the Zn/Cr-MOFs/TiO2 composites employed for simulating levofloxacin hydrochloride in wastewater. The impact of the mass of the Zn/Cr-MOFs/TiO2 composite, concentration of levofloxacin hydrochloride, solution pH, and temperature on the adsorption performance was investigated. Experimental findings indicated that at pH 6, the maximum removal efficiency of levofloxacin hydrochloride by the Zn/Cr-MOFs/TiO2 composite was achieved at 88.8%, with an adsorption capacity of 246.3 mg/g. To analyze the experimental data, both pseudo-first-order and pseudo-second-order kinetics models were applied, revealing that the pseudo-second-order model provided a better fit to the data. Additionally, Langmuir and Freundlich isotherm models were used to study equilibrium adsorption behavior and showed good agreement with both kinetic modeling and Langmuir isotherm analysis results. These observations suggest that monolayer adsorption predominates during the removal process of levofloxacin hydrochloride by Zn/Cr-MOFs/TiO2 composites.

16.
Polymers (Basel) ; 16(17)2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39274139

RESUMO

To reduce the mercury content in flue gas from coal-fired power plants and to obtain high-performance, low-cost mercury adsorbents, a novel composite material was prepared by structural design through the in situ growth method. Functionalization treatments such as the modification of functional groups and multilayer loading of polymetallic were conducted. These materials include the MOF material UiO-66 and modified biochar doped with Fe/Ce polymetallic, both of which contain unsaturated metal centrals and oxygen-containing functional groups. On the basis of obtaining the effects of adsorption temperature and composite ratio on the Hg0 removal characteristics, coupling and synergistic mechanisms between the various types of active centers included were investigated by using a variety of characterization and analysis tools. The active adsorption sites and oxidation sites were identified during this process, and the constitutive relationship between the physicochemical properties and the performance of Hg0 removal was established. The temperature-programmed desorption technique, Grand Canonical Monte Carlo simulation, and adsorption kinetic model were employed to reveal the mechanism of Hg0 removal. The results showed that the UiO-66-Br@MBC composite adsorbent possessed an excellent Hg0 removal performance at adsorption temperatures ranging from 50 to 250 °C, and targeted construction of adsorption and oxidation sites while maintaining thermal stability. The Hg0 removal by the composites is the result of both adsorption and oxidation. The micropores and small pore mesopores in the samples provide physical adsorption sites. The modified biochar acts as a carrier to facilitate the full exposure of the central metal zirconium ions, the formation of more active sites, and the process of electron transfer. The doping modification of the Br element can enhance the overall redox ability of the sample, and the introduced Fe and Ce polymetallic ions can work in concert to promote the oxidation process of Hg0. The excellent regulation of the ratio between adsorption and oxidation sites on the surface of the composite material finally led to a significant boost in the samples' capacity to remove Hg0.

17.
Materials (Basel) ; 17(17)2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39274603

RESUMO

Tuning a material's hydrophobicity is desirable in several industrial applications, such as hydrocarbon storage, separation, selective CO2 capture, oil spill cleanup, and water purification. The introduction of fluorine into rare-earth (RE) metal-organic frameworks (MOFs) can make them hydrophobic. In this work, the linker bis(trifluoromethyl)terephthalic acid (TTA) was used to make highly fluorinated MOFs. The reaction of the TTA and RE3+ (RE: Y, Gd, or Eu) ions resulted in the primitive cubic structure (pcu) exhibiting RE dimer nodes (RE-TTA-pcu). The crystal structure of the RE-TTA-pcu was obtained. The use of the 2-fluorobenzoic acid in the synthesis resulted in fluorinated hexaclusters in the face-centered cubic (fcu) framework (RE-TTA-fcu), analogous to the UiO-66 MOF. The RE-TTA-fcu has fluorine on the linker as well as in the cluster. The MOFs were characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, thermogravimetric analysis, and contact angle measurements.

18.
Chemosphere ; 364: 143253, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39233292

RESUMO

Developing adsorbents suitable for industrial applications that can effectively enhance the separation of methane (CH4) from nitrogen (N2) in coalbed gas is crucial to improve energy recovery and mitigate greenhouse gas emissions. In this study, three modification strategies were implemented on Zr-FUM, including ligand regulation, metal replacement, and ligand doping, to synthesize Zr-FDCA, Al-FUM, and Zr-FUM-FA, with the aim of improving the performance of CH4/N2 separation under humid conditions. The results demonstrated that the promotion of robust orbital overlap and strengthened electrovalent bonding on adsorbents can selectively enhance CH4 adsorption. As a result, Zr-FUM-FA achieved a saturated CH4 adsorption capacity of 1.37 mmol/g, a CH4 working window of 307 s, and a CH4/N2 sorbent selection parameter (Ssp) of 47.31, exceeding the performance of most reported adsorbents. Analyses of the pore structure, surface morphology, and functional groups revealed that the presence of an ultramicropore proximity to CH4, reduced static resistance, and enhanced electrovalent bond were key factors for CH4 separation. Grand Canonical Monte Carlo and Density Functional Theory studies indicated that the introduction of -C-H- in FA played a crucial role in enhancing CH4 adsorption. Optimization of adsorption parameters using the Aspen adsorption package showed that in a dual-adsorbent bed system, the recovery and purity of CH4 in Zr-FUM-FA reach 99.5% and 97.3%, respectively, providing important theoretical support for the improvement of CH4 recovery in the pressure swing adsorption process from coalbed gas.


Assuntos
Metano , Zircônio , Adsorção , Metano/química , Zircônio/química , Ligantes , Carvão Mineral , Nitrogênio/química , Poluentes Atmosféricos/química , Poluentes Atmosféricos/análise
19.
Chemosphere ; 366: 143369, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39307470

RESUMO

The efficiency and stability of the electrical activation of persulfate (PS) by transition metal-based cathode are controlled by the cycling of Fe(III)/Fe(II) and the mass transfer of PS. In this study, the mixed-valence MOFs catalyst (FeII-MIL-53(Fe)) modified flow-through cathode was prepared for the first time. FeII-MIL-53(Fe) was prepared by replacing part of the iron-oxygen network structure in MIL-53(Fe) with Fe(II), resulting in the formation of coordinated unsaturated iron centers (CUICs). The increase of the Fe(III) CUICs facilitated the conversion of Fe(III) to Fe(II). Furthermore, the cycling of Fe(III)/Fe(II) was further promoted by the electric field. Meanwhile, the hydrodynamic behavior of flow-through cathode was indicated by the computational fluid dynamics (CFD) simulation. The quenching experiments and electron paramagnetic resonance (EPR) results showed that several reactive specie (SO4·-, ·OH, O2·- and 1O2) were produce. In summary, this work provided an effective strategy for the efficient and stable electrical activation of PDS.

20.
Chemosphere ; 365: 143312, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39265732

RESUMO

Global warming has been mainly attributed to the excessive release of carbon dioxide (CO2) to the atmosphere. Several CO2 capture and conversion technologies have been developed in the past few decades with their own merits and limitations. Electrochemical conversion of CO2 is one of the most attractive techniques for combating CO2 emissions. However, the efficacy of the electrochemical reduction of CO2 hinges on the efficiency of the utilized materials (i.e., electrocatalysts). Metal organic frameworks (MOFs)-based materials have recently emerged as attractive tools for various applications, including the electrochemical conversion of CO2. Although there are some review articles on CO2 capture and conversion using different materials, reviews focusing specifically on the electrochemical conversion of CO2 using MOFs-based materials are still comparatively lacking. Additionally, the field of electrochemical conversion of CO2 into valuable chemicals is currently gaining high momentum, requiring comprehensive and recent reviews, which would provide researchers/professionals with a quick and easy access to the recent developments in this rapidly evolving research area. Accordingly, this article comprehensively reviews recent studies on the electrochemical conversion of CO2 using pristine/modified/functionalized MOFs as well as composite materials containing MOFs. Additionally, single atom catalysts (SACs) derived from MOFs and their applications for the electrochemical conversion of CO2 has also been reviewed. Furthermore, obstacles, challenges, limitations, and remaining research gaps have been identified, and future works to tackle them have been highlighted. Overall, this review article provides valuable discussion and insights into the recent advancements in the field of electrochemical conversion of CO2 into chemicals using MOFs-based materials.


Assuntos
Dióxido de Carbono , Técnicas Eletroquímicas , Estruturas Metalorgânicas , Dióxido de Carbono/química , Estruturas Metalorgânicas/química , Técnicas Eletroquímicas/métodos , Catálise , Aquecimento Global/prevenção & controle
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