Search Results (623)

Efficient detection of heavy metal ions in complex marine environments is essential to the safety of marine organisms and human beings. This study developed a novel screen-printed-electrode (SPE) electrochemical sensor for rapid on-site determination of typical heavy metal ions such as Cu²⁺, Pb²⁺, Cd²⁺, and Hg²⁺ in seawater. The sensor employs a three-electrode system, with the working electrode modified with a composite of metal–organic framework-derived carbon (MOF-C) and multiwalled carbon nanotubes (MWCNTs), thereby significantly enhancing detection sensitivity and selectivity. By optimizing square-wave anodic stripping voltammetry (SWASV) parameters, detection limits of 0.83, 0.40, 1.05, and 0.30 μM for the detection of Cu²⁺, Pb²⁺, Cd²⁺, and Hg²⁺ ions were achieved. In mixed-ion detection, excellent peak separation and strong resistance to interferences were demonstrated. Experimental results demonstrate that the sensor exhibits good linear response, excellent interference resistance, and high practicality, providing a new approach for rapid on-site determination of heavy metal pollution in marine environments. Full article

The pursuit of sustainable ammonia production has accelerated the development of electrocatalytic pathways capable of operating under ambient conditions with renewable electricity. Recent studies have revealed that the efficiency and selectivity of both electrochemical nitrogen reduction reaction (eNRR) and nitrate reduction reaction (eNO₃RR) are not governed solely by catalyst composition, but by the synergistic interplay among electrolyte identity, interfacial solvation structure, and catalyst architecture. Hydrated cations such as Li⁺ profoundly reshape the electric double layer, polarize interfacial water, and lower activation barriers for key proton–electron transfer steps, thereby redefining the electrolyte as an active promoter. Parallel advances in structural engineering, including alloying, heteroatom doping, controlled defect formation, and nanoscale morphological control, have enabled the optimization of intermediate adsorption energies while simultaneously suppressing competing hydrogen evolution. In addition, the emergence of metal–organic-framework (MOF)-derived single-atom catalysts has demonstrated that atomically dispersed transition-metal centers anchored within dynamically adaptable matrices can deliver exceptional Faradaic efficiencies, high turnover rates, and long-term operational durability. These developments highlight a unified strategy in which electrolyte–catalyst coupling, rational structural modification, and atomic-scale design principles converge to enable predictable and high-performance ammonia electrosynthesis. This review integrates mechanistic insights across these domains and outlines future directions for translating molecular-level understanding into scalable technologies for green ammonia production. Full article

Gas sensors are essential in areas such as environmental monitoring, industrial safety, and healthcare, where the accurate detection of hazardous and volatile gases is crucial for ensuring safety and well-being. Metal–organic frameworks (MOFs), which are crystalline porous materials composed of metal nodes and organic linkers, have recently emerged as a versatile platform for gas sensing due to their adjustable porosity, high surface area, and diverse chemical functionality. This review provides a detailed overview of MOF-based gas sensors, beginning with the fundamental sensing mechanisms of physisorption, chemisorption, and charge transfer interactions with gas molecules. We explore design strategies, including functionalization and the use of composites, which improve sensitivity, selectivity, response speed, and durability. Particular attention is given to the influence of MOF morphology, pore size engineering, and framework flexibility on adsorption behavior. Recent developments are showcased across various applications, including the detection of volatile organic compounds (VOCs), greenhouse gases, toxic industrial chemicals, and biomedical markers. Finally, we address practical challenges such as humidity interference, scalability, and integration into portable platforms, while outlining future opportunities for real-world deployment of MOF-based sensors in environmental, industrial, and medical fields. This review highlights the potential of MOFs to transform next-generation gas sensing technology by integrating foundational material design with real-world applications. Full article

Cellulose nanofibers/metal-organic framework (CNFs/MOF) composites hold promise for energy storage thanks to high porosity, large specific surface area, and inherent flexibility, but their poor conductivity limits applications to environmental remediation and gas adsorption. Herein, flexible CNFs served as substrates for in situ growth of continuous ZIF-8 nanolayers via interfacial synthesis, with a CNFs/ZIF-8 gel network built to enhance structural integrity and flexibility. A novel strategy first regulated the layered pore structure: ZIF-8 in CNFs/ZIF-8 nanofibers was etched in the acidic environment of aniline in situ polymerization, constructing a hierarchical porous architecture with interconnected micropores and mesopores. CNFs/ZIF-8/PANI gel composite membranes were then fabricated. As self-supporting electrodes for symmetric supercapacitors, the composites showed excellent electrochemical performance: 1350 F/g at 1 A/g for the electrode, and the flexible solid-state device delivered a specific capacitance of 220.9 F/g at 0.5 A/g, along with a capacitance retention rate of 74% after 5000 charge–discharge cycles at 10 A/g. The superior performance stems from synergistic hierarchical pore structure regulation via partial MOF sacrificial templating and gel matrix-mediated rapid ion diffusion, offering a feasible approach for high-performance flexible energy storage devices. Full article

Soil amendments play a critical role in improving soil health and supporting sustainable crop production, especially under declining soil fertility and climate-related stress. However, their impact varies because each amendment influences the soil through different biogeochemical processes rather than a single universal mechanism. This review synthesizes current knowledge on a wide range of soil amendments, including compost, biosolids, green and animal manure, biochar, hydrochar, bagasse, humic substances, algae extracts, chitosan, and newer engineered options such as metal–organic framework (MOF) composites, highlighting their underlying principles, modes of action, and contributions to soil function, crop productivity, and soil carbon dynamics. Across the literature, three main themes emerge: improvement of soil physicochemical properties, enhancement of nutrient cycling and nutrient-use efficiency, and reinforcement of plant resilience to biotic and abiotic stresses. Organic nutrient-based amendments mainly enrich the soil and build organic matter, influencing soil carbon inputs and short- to medium-term increases in soil organic carbon stocks. Biochar, hydrochar, and related materials act mainly as soil conditioners that improve structure, water retention, and soil function. Biostimulant-type amendments, such as algae extracts and chitosan, influence plant physiological responses and stress tolerance. Humic substances exhibit multifunctional effects at the soil–root interface, contributing to improved nutrient efficiency and, in some systems, enhanced carbon retention. The review highlights that no single amendment is universally superior, with outcomes governed by soil–crop context. Its novelty lies in its mechanism-based, cross-amendment synthesis that frames both yield and carbon outcomes as context-dependent rather than universally transferable. Within this framework, humic substances and carbon-rich materials show potential for climate-smart soil management, but long-term carbon sequestration effects remain uncertain and context-dependent. Full article

Metal–organic frameworks (MOFs) typically exist in the form of powders or dispersed crystals, which limits their direct application in practical engineering scenarios that require monolithic structures and processability. To address this issue, the present study successfully anchored MOF (zeolitic imidazolate framework-8, ZIF-8) nanocrystals within a porous silicon carbide (p-SiC) substrate via a facile in situ growth strategy, achieving both stable macroscopic loading and intimate microscopic interfacial bonding. The resulting ZIF-8/p-SiC composite exhibits a hierarchical porous structure, with a specific surface area approximately 183 times higher than that of the raw p-SiC, alongside a substantially enhanced CO₂ adsorption capacity. By utilizing a low-cost p-SiC support and mild ZIF-8 synthesis conditions, this work demonstrates excellent reproducibility and scalability, providing a facile and effective pathway for fabricating MOF/porous media composite systems that possess both superior mechanical properties and tailored pore structures. Additionally, the developed MOF/p-SiC composites can serve as controllable rock-analog porous media, offering new perspectives for investigating MOF-rock interfacial interactions and CO₂ geological sequestration mechanisms, thereby establishing an organic link between fundamental materials science and geological engineering applications. Full article

Metal–organic framework (MOF)-based surface-enhanced Raman scattering (SERS) sensors have emerged as a versatile platform for high-sensitivity and selective detection in agricultural, environmental, and biomedical applications. By integrating plasmonic nanostructures with tunable MOF architectures, these hybrid systems combine ultrahigh signal enhancement with molecular recognition, analyte preconcentration, and controlled hotspot distribution. This review provides a comprehensive overview of the fundamental principles underpinning MOF–SERS performance, including EM and chemical enhancement mechanisms, and highlights strategies for substrate design, such as metal–MOF composites, plasmon-free frameworks, ligand functionalization, and hierarchical or core–shell architectures. We further examine their applications in environmental monitoring, pesticide and contaminant detection, pathogen identification, biomarker analysis, and theranostics, emphasizing real-sample performance, molecular selectivity, and emerging integration with portable Raman devices and AI-assisted data analysis. Despite notable advances, challenges remain in reproducibility, quantitative reliability, matrix interference, scalability, and biocompatibility. Future developments are likely to focus on rational MOF design, sustainable fabrication, intelligent spectral interpretation, and multifunctional integration to enable robust, field-deployable sensors. Overall, MOF-based SERS platforms represent a promising next-generation analytical tool poised to bridge laboratory innovation and practical, real-world applications. Full article

Photocatalysis driven by the visible light of solar energy has received considerable attention in the field of environmental remediation and clean energy production. In this work, monomeric sulfonated palladium phthalocyanine (PdPcS) was encapsulated in zeolitic imidazolate frameworks-8 (ZIF-8) crystals (denoted PdPcS@ZIF-8) through electrostatic interaction in the ammonia system, while their photocatalytic activity was well-maintained together with the structural regularity of ZIF-8 crystals. For comparison, a PdPcS/ZIF-8 sample was obtained from the traditional impregnation method. The ¹³C NMR and UV-DRS spectra confirmed the difference between PdPcS@ZIF-8 and PdPcS/ZIF-8 in terms of the chemical environment effect for PdPcS. Under visible light, the optimal PdPcS@ZIF-8 catalyst achieved complete degradation of 0.1 mM bisphenol A in 120 min. It also exhibited excellent stability, retaining 81.5% activity after four cycles, far outperforming the impregnated sample (32.5%) due to effective encapsulation preventing PdPcS leaching. This versatile one-step synthetic strategy is expected to be useful for designing novel macromolecules@MOF composite materials. Full article

The escalating global water crisis demands the development of cost-effective and environmentally sustainable treatment technologies. Among various advanced oxidation processes (AOPs), peracetic acid (PAA) has emerged as a promising oxidant, owing to its high redox potential, chemical stability, and potent disinfection capability. Nevertheless, the lack of highly efficient catalysts remains a major obstacle to achieving the effective degradation of contaminants of emerging concern in wastewater. Heterogeneous catalysis has proven to be a viable strategy for enhancing PAA activation, highlighting the urgent need for catalysts with superior activity, stability, and recyclability. Metal–organic frameworks (MOFs), with their large surface areas, tunable porosity, and structural diversity, provide versatile platforms for catalyst design. Recently, MOF-derived materials have attracted increasing attention for PAA activation, offering a new frontier in advanced oxidation technologies for efficient and sustainable wastewater remediation. This review systematically examines the role of MOFs in PAA activation, from pristine frameworks to MOF-based composites and MOF-derived catalysts. Mechanistic insights into PAA activation are highlighted, strategies for engineering MOF-based composites with synergistic catalytic properties are discussed, and the transformation of MOFs into robust derivatives with improved stability and reactivity is explored. Special attention is given to the identification and quantification of reactive species generated in PAA systems, providing a critical understanding of reaction pathways and catalytic performance. Finally, current challenges and future directions are outlined for designing highly efficient, recyclable, and environmentally compatible MOF-based catalysts, emphasizing their potential to significantly advance PAA-based AOPs. Full article

Metal-organic frameworks (MOFs) offer high porosity for water remediation but face challenges in handling as powders. We address these limitations by physically immobilizing Fe–BTC MOF within calcium-crosslinked low-methoxyl pectin matrices (PE–Ca–MOF). Solvent-cast films and freeze-dried foams were fabricated using water-based and polyvinylpyrrolidone (PVP)-assisted Fe–BTC dispersions, preserving MOF and pectin structures confirmed by FT–IR. PVP improved Fe–BTC dispersion and reduced particle size, enhancing distribution and plasticizing the matrix proved by DSC. Incorporation of water-dispersed Fe–BTC increased the equilibrium adsorption capacity but reduced the initial adsorption rate, while the PVP-assisted foam further enhanced uptake in comparative batch tests through its more open porous structure. At pH 7, PE–Ca–5%MOF films showed high adsorption capacities and removal efficiencies for paraquat (35.5 mg/g, 70.6%) and tetracycline (14.5 mg/g, 46.8%), while maintaining Zn²⁺ uptake compared to calcium-pectin films without MOF. Adsorption followed pseudo-first-order kinetics and Langmuir isotherms. Green regeneration with acetic acid enabled >80% capacity retention over five adsorption–desorption cycles. Foam architectures increased porosity and active-site accessibility (SEM), improving performance even at lower MOF loadings. Overall, controlling MOF dispersion and composite morphology enables efficient, reusable, and environmentally friendly bio-based adsorbents for water purification. Full article

To obtain an excellent electromagnetic wave (EMW) absorption material, a strategy was proposed in this study with the aid of in-situ growth of carbon nanotubes (CNTs) on the surface of a metal–organic framework (MOF)-derived FeCoNiMnMg high-entropy alloy (HEA). The HEA@CNT composite was successfully prepared via a solvothermal method combined with a one-step pyrolysis process. With the pyrolysis temperature increasing from 600 °C to 800 °C, the length of CNTs grew from 200 nm to about 600 nm approximately, while the defect density of CNTs was enhanced. This structural evolution significantly improved the dielectric properties and impedance matching. Consequently, the sample prepared at 800 °C (HEA@CNT-800) exhibited outstanding microwave absorption performances, achieving a minimum reflection loss (RL_min) of −57.52 dB at a matched thickness of 2.3 mm and an effective absorption bandwidth (EAB) of 4.4 GHz at a thinner thickness of 1.9 mm. This work provides a novel perspective for designing high-performance MOF-derived absorption materials. Full article

It is understood that 4-nitrophenol (4-NP) and its derivatives/isomers, such as m-NP and o-NP, are considered toxic nitroaromatic pollutants that pose health risks for human beings and have negative impacts on the environment. Therefore, monitoring of 4-NP is of particular importance to avoid the negative impacts of these environmental pollutants on aquatic life and human health. Electrochemical sensors have emerged as the most promising next-generation technology for the detection of environmental pollutants. The electrochemical method has been extensively used for the detection of 4-NP, p-NP, etc., which has delivered an interesting electrochemical performance. This review provides an overview of the advances in electrode modifiers designed for the electrochemical detection of 4-NP and its isomers. This review includes the use of carbon-based materials, metal oxides, metal sulfides, metal-organic-frameworks (MOFs), conducting polymers, MXenes, covalent organic frameworks (COF), and composites for the development of 4-NP electrochemical sensors. Various electrochemical techniques, such as differential pulse voltammetry, square wave voltammetry, linear sweep voltammetry, cyclic voltammetry (CV), electrochemical impedance spectroscopy, and amperometry, are discussed for the detection of 4-NP and other isomers. Full article

Widespread antibiotic residues in aquatic environments pose escalating threats to ecological stability and human health, highlighting the urgent demand for effective remediation strategies. In recent years, photocatalytic technology based on advanced nanomaterials has emerged as a sustainable and efficient strategy for antibiotic degradation, enabling the effective utilization of solar energy for environmental remediation. This review provides an in-depth discussion of six representative categories of photocatalytic nanomaterials that have demonstrated remarkable performance in antibiotic degradation, including metal oxide-based systems with defect engineering and hollow architectures, bismuth-based semiconductors with narrow band gaps and heterojunction designs, silver-based plasmonic composites with enhanced light harvesting, metal–organic frameworks (MOFs) featuring tunable porosity and hybrid interfaces, carbon-based materials such as g-C₃N₄ and biochar that facilitate charge transfer and adsorption, and emerging MXene–semiconductor hybrids exhibiting exceptional conductivity and interfacial activity. The photocatalytic performance of these nanomaterials is compared in terms of degradation efficiency, recyclability, and visible-light response to evaluate their suitability for antibiotic degradation. Beyond parent compound removal, we emphasize transformation products, mineralization, and post-treatment toxicity evolution as critical metrics for assessing true detoxification and environmental risk. In addition, the incorporation of artificial intelligence into photocatalyst design, mechanistic modeling, and process optimization is highlighted as a promising direction for accelerating material innovation and advancing toward scalable, safe, and sustainable photocatalytic applications. Full article

The integration of graphene-based materials with metal–organic frameworks (G@MOFs) has emerged as a promising strategy for advanced wastewater treatment owing to their synergistic physicochemical properties. This review systematically compiles and critically analyzes recent advances in the synthesis, structural characterization, and application of G@MOFs for the removal of organic and inorganic micropollutants. Special emphasis is placed on how the unique combination of high surface area, tunable pore structures, and abundant active sites in G@MOFs enhances adsorption, photodegradation, and catalytic degradation mechanisms. Compared to conventional adsorbents and standalone MOFs, G@MOFs exhibit superior removal capacities, stability, and reusability. This paper also identifies key challenges in large-scale applications, regeneration, and potential environmental risks, providing a future outlook on optimizing synthesis routes and tailoring functional composites for sustainable water treatment technologies. The novelty of this review lies in providing the first dedicated, systematic evaluation of G@MOFs for wastewater micropollutant removal, integrating synthesis strategies, performance benchmarking, techno-economic aspects, environmental safety, and future application prospects into a unified framework. Full article

Polyphenols like dihydroquercetin, rutin, and rifampicin show promise for Alzheimer’s disease (AD) therapy due to their ability to inhibit amyloid-β (Aβ) aggregation and reduce reactive oxygen species (ROS), garnering significant recent interest. However, their efficacy is substantially diminished because excess metal ions present in amyloid plaques can chelate these compounds. Therefore, reshaping the metal microenvironment in the patient’s brain is particularly important for the therapeutic effect of AD. To address the above issues, we have constructed a composite system formed by NH₂-MIL-101(Fe) (MOF), dihydroquercetin (DHQ), and D-penicillamine (D-pen). Due to the lack of π-π interaction and the low adsorption energy between D-pen/MOF, the release order and speed of D-pen was much faster than DHQ, thus achieving metal microenvironment regulation and ensuring the therapeutic effect of DHQ. In a 5 × FAD transgenic mouse model, DD@MOF treated and improved spatial learning and memory deficits. Therefore, the DD@MOF based on polyphenolic compounds provides a potential research direction for intervention in Alzheimer’s disease through chelating copper ions and antioxidant properties. Full article