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In this study, we successfully demonstrate the synthesis of a novel necklace-like Co, Fe, and N co-doped one-dimensional (1D)-assembly of hollow carbon nanoboxes (1D-HCNB-x) and its potential for supercapacitor application.

This paper reviewed the properties and relationship of reactive oxygen species and anions in persulfate-based advanced oxidation processes for saline organic wastewater treatment.

Heterogeneous Fenton-like processes are very promising methods of treating organic pollutants through the generation of reactive oxygen containing radicals. Herein, we report novel 0D–1D hybrid nanoarchitectonics (necklace-like structures) consisting of FeCo@N–C yolk–shell nanoreactors as advanced catalysts for Fenton-like reactions. Each FeCo@N–C unit possesses a yolk–shell structure like a nanoreactor, which can accelerate the diffusion of reactive oxygen species and guard the active sites of FeCo. Furthermore, all the nanoreactors are threaded along carbon fibers, providing a highway for electron transport. FeCo@N–C nano-necklaces thereby exhibit excellent performance for pollutant removal via activation of peroxymonosulfate, achieving 100% bisphenol A (k = 0.8308 min−1) degradation in 10 min with good cycling stability. The experiments and density-functional theory calculations reveal that FeCo dual sites are beneficial for activation of O–O, which is crucial for enhancing Fenton-like processes., Novel 0D–1D hybrid nanoarchitectonics consisting of FeCo@N–C yolk–shell nanoreactors are developed for Fenton-like reaction. With the multilevel advantages of this design, FeCo@N–C nano-necklaces exhibit excellent performance for BPA removal.

Highly efficient single atom catalysts are critical to substantially promote for peroxymonosulfate (PMS) activation to organic pollutant degradation, but it remains a challenge at present. Herein, single atom Mn anchored on N-doped porous carbon (SA-Mn-NSC) was synthesized by ball milling of Mn-doped carbon nitride and spirulina biochar to dominantly activate PMS. The precursor of carbon nitride and spirulina possessed a strong coordinating capability for Mn(II), facilitating the formation of highly dispersed nitrogen-coordinated Mn sites (Mn-N

Developing new catalysts for efficient degradation of micropollutants in water is of significant importance in advanced oxidation processes (AOPs). Herein, TiO

Integrating pseudocapacitive materials with a conductive carbonaceous matrix is an efficient method to improve their capacitive deionization (CDI) performance. However, it remains a challenge to optimize the structure and chemical component of each part and strengthen the internal bonding between them for the further improvement of salt adsorption capacity (SAC). Herein, we report an ultrafine anatase TiO2/carbon nanocomposite confined into N-doped mesoporous carbon (TiO2/C@NMC) via a mesostructured polydopamine (mPDA) coated MOF strategy and subsequent pyrolysis. During the pyrolysis process, the mPDA shell could construct a spatially confined environment to effectively limit the aggregation of TiO2 nanoparticles and restrain their transformation into the rutile phase, contributing to the abundant faradaic active sites and strong interaction with a conductive carbon matrix. Moreover, the mPDA shell-derived N-doped mesoporous carbon provides abundant ion diffusion channels and alleviates the volume variation of the inner faradaic materials during the adsorption/desorption process. As a result, TiO2/C@NMC delivers an excellent SAC of 27.73 mg g−1 and stable regeneration properties over 50 cycles, demonstrating its great potential as a superior pseudocapacitive electrode for hybrid CDI (HCDI). This work offers a promising strategy to regulate the properties of pseudocapacitive materials for designing advanced HCDI devices.

Carbon-based electrodes play important roles in constructing efficient capacitive deionization (CDI) devices. Therefore, the rational design of carbon materials with optimized structure, composition, and morphology is crucial for further improving the CDI performance. Herein, a novel N, P co-doped eave-like hierarchical porous carbon (NP-EHPC) for CDI is reported. To prepare the NP-EHPC, the core–shell ZIF-8@AF particles are first prepared through the kinetically-controlled growth of zeolitic imidazolate framework-8 (ZIF-8) and polymerization of p-aminophenol and formaldehyde (AF), followed by subsequent pyrolysis and post-doping with phosphorus. Owing to the unique eave-like morphology, presence of abundant mesopores, and co-doping of P and N, the NP-EHPC exhibits a high desalination capacity of 24.14 mg g−1 in 500 mg L−1 NaCl solution at 1.2 V and long cycling stability of over 150 cycles. Moreover, the density functional theory (DFT) calculation results reveal that the co-doping of N and P atoms can greatly enhance the binding energies for Na and Cl atoms and lead to superior electrosorption capacity. This work provides a new insight into the design of high-performance carbon materials for the desalination of brackish water.

Metal–organic framework (MOF) derived carbon-based nanocatalysts have received great attention in environmental remediation application. However, the aggregation and poor separation characteristics...

Selective removal of organic pollutants from surface water with high efficiency is crucial in water purification. Here, yolk-shell Co/C nanoreactors (YSCCNs) are facilely synthesized via pyrolysis of controllably etched ZIF-67 by tannic acid, and their degradation performance on multiple pollutants is demonstrated. To present the structure-performance relationship between the designed nanocatalyst and the selective removal of organic pollutants, bisphenol A (BPA) was selected as the targeted pollutant with coexistence of humus acid (HA). For comparison, solid and hollow ZIF-67 derived Co/C nanoparticles denoted as SCCNs and HCCNs, were also tested. The results show that YSCCNs exhibit enhanced BPA degradation rate of 0.32 min-1, which is 23.1% and 45.4% higher than that of HCCNs and SCCNs in HA (10 ppm) system. The essential improvement can be ascribed to the synergetic effects from shell layer (size-exclusion) and core/shell (confinement effect). The degradation mechanism and pathway are further confirmed by radical quenching experiments and liquid chromatography-mass spectrograph (LC-MS), respectively. In addition, some influential factors, including reaction temperature, pH value, and peroxymonosulfate (PMS) dosage are investigated in detail. This work provides a possible way to selectively remove target contaminant from multiple pollutants in complex water system.

Over the past decades, the development of porous materials has directly or indirectly affected industrial production methods. Metal-organic frameworks (MOFs) as an emerging class of porous materials exhibit some unique advantages, including controllable composition, a large surface area, high porosity, and so on. These attractive characteristics of MOFs have led to their potential applications in energy storage and conversion devices, drug delivery, adsorption and storage, sensors, and other areas. However, powdered MOFs have limited practical applications owing to poor processability, safety hazards from dust formation, and poor recyclability. In addition, the inherent micro/mesoporosities of MOFs also reduce the accessibility and diffusion kinetics for large molecules. To improve their processability for practical applications, MOFs are often deposited as MOF layers or films (i.e., MOF-coated composites) on supporting materials or are formed into 3D structured composites, such as aerogels and hydrogels. In this article, we review recent researches on these MOF composites, including their synthetic methods and potential applications in energy storage devices, heavy metal ion adsorption, and water purification. Finally, the future outlook and challenges associated with the large-scale fabrication of MOF-based composites for practical applications are discussed.

Summary In recent years, metal-organic framework (MOF)-derived carbon materials (CMs), known for their nanoporous structure yielding a high surface area and tunable chemical and physical properties, have drawn great interest in many fields of application, such as energy storage and conversion, environmental remediation, and catalysis. Despite the tremendous efforts involved in their development, several common drawbacks still persist during the carbonization process: (1) the intrinsic nature of micropore-dominated porous structure (limited diffusion), (2) the irreversible aggregation of metal nanoparticles, and (3) the poor control over structural evolution, which largely thwart their performance. To overcome these technical limitations, many new strategies are currently emerging to boost the development of MOF-derived nanoarchitectured CMs (NCMs). These new approaches can be considered new chemistry tools utilizing SiO2, polymers, surfactants, and others. In this review, we focus on the synthetic mechanisms of these new methods by summarizing recent findings related to MOF-derived NCMs.

The organized assembly of nanoparticles into complex macroarchitectures opens up a promising pathway to create functional materials. Here, we demonstrate a scalable strategy to fabricate macroarchitectures with high compressibility and elasticity from hollow particle-based carbon nanofibers. This strategy causes zeolitic imidazolate framework (ZIF-8)-polyacrylonitrile nanofibers to assemble into centimetre-sized aerogels (ZIF-8/NFAs) with expected shapes and tunable functions on a large scale. On further carbonization of ZIF-8/NFAs, ZIF-8 nanoparticles are transformed into a hollow structure to form the carbon nanofiber aerogels (CNFAs). The resulting CNFAs integrate the properties of zero-dimensional hollow structures, one-dimensional nanofibers, and three-dimensional carbon aerogels, and exhibit a low density of 7.32 mg cm

Correction for ‘Co, Fe and N co-doped 1D assembly of hollow carbon nanoboxes for high-performance supercapacitors’ by Minjun Kim et al., J. Mater. Chem. A, 2022, 10, 24056–24063, https://doi.org/10.1039/D2TA06950D.

Fluoride in the hydrosphere exceeds the standard, which could be critically hazardous to human health and the natural environment. The adsorption method is a mature and effective way to remove pollutants in water, including fluoride. In this study, we synthesized three kinds of cerium-based metal-organic frameworks (Ce-MOFs) with different structures and properties by modulating the organic ligands (i.e., trimesic acid (BTC), 1,2,4,5-benzenetetracarboxylic acid (PMA), and terephthalic acid (BDC)) via the solvothermal method. The adsorption kinetics of Ce-MOFs on fluoride well fit the pseudo second order model, and their adsorption isotherms also conform to Langmuir isothermal model. The thermodynamic study reveals that the adsorption process is a spontaneous endothermic reaction. The maximum saturated adsorption capacities of Ce-BTC, Ce-PMA, and Ce-BDC are 70.7, 159.6, and 139.5 mg g

Zirconium-based metal–organic framework nanosheet assembled hydrangea-like architectures were reported and an enhanced iodine capture capacity was achieved.

In this study, three-dimensional (3D) ZIF-8-derived carbon (ZIF-8C) polyhedrons have been successfully coated with polydopamine (PDA) nanothin layer via a facile synthetic method that exploits oxidative self-polymerization of dopamine in alkaline solutions. It is observed that ca. 20 nm of PDA nanothin film is coated on ZIF-8C surface with a good homogeneity. Our results show clear morphological changes in core-shell structured PDA-coated ZIF-8C (ZIF-8C@PDA) as compared to bare ZIF-8C. In addition, the cyclic voltammetry shows conspicuous redox peaks in ZIF-8C@PDA. The observed redox activity is attributed to a series of redox reactions of oxygen species of catechol and quinone groups of PDA. With superior adhesive property and redox activity as additional surface functionality, ZIF-8C@PDA can be used in various applications, especially in energy storage applications in the future.

The rational design of active and sustainable heterogeneous catalysts towards advanced oxidation process (AOPs) is of great significance for water remediation. Here, we synthesized Fe0/graphitized carbon composite catalysts for efficient removal of bisphenol A (BPA) by activating peroxymonosulfate (PMS). The Fe0/graphitized carbon composites were obtained by the pyrolysis of iron-tannic modified cotton, where tannic acid (TA) is an eco-friendly and low-cost polyphenol that can strongly form complexes with iron ions. The introduction of iron could significantly regulate the graphitization of carbon by changing the pyrolysis temperature. The combination of Fe0 and graphitized carbon can endow Fe-TCs with an enhanced adsorption ability due to strong complexation between Fe0 and BPA. The pyrolysis of iron-tannic modified cotton may serve as a novel strategy to design an efficient low-toxic metal-carbon catalyst for sulfate radical based processes in water remediation.

Carbon materials, especially N-doped carbon materials with a one-dimensional (1D) hollow structure, have attracted great attention as one of the most efficient and eco-friendly catalysts for advanced oxidation processes (AOPs). The complex synthesis process of 1D hollow carbon however remains a major challenge in meeting the growing demand for it as a superior carbon-based catalyst. Herein, we demonstrate a facile strategy to synthesize 1D hollow carbon nanofibers (HCNFs) in a scalable manner. In this study, zeolitic imidazolate framework-8 (ZIF-8)/polyacrylonitrile (PAN) fibers were fabricated via electrospinning, and subsequent pyrolysis of the as-prepared ZIF-8/PAN composite nanofibers produced HCNFs. With excellent structural advantages and N-doped composition, HCNFs exhibited a remarkable level of catalytic degradation of tetracycline (TC) in the peroxymonosulfate (PMS) activation system. Furthermore, the HCNFs also showed good mechanical flexibility. A catalytic device was then constructed to explore the potential applications of HCNFs.

The degradation of organic contaminants under high salinity condition is still a challenge for environmental remediation due to the inhibiting effect resulted from the side reactions between radicals and anions. Here, we demonstrate the non-radical oxidation process via peroxymonosulfate (PMS) activation by metal-free carbon catalyst for efficiently decomposing bisphenol A (BPA) in saline water. The nitrogen-doped graphitic carbon (NGC700) exhibits excellent catalytic activity for depredating BPA at acid and neutral pH. Based on the scavenger experiments and electron paramagnetic resonance (EPR) analyses, the mechanism of catalytic oxidation was elucidated as the non-radical pathway, and singlet oxygen was identified as the primary reactive species. Experiments on the influence of anions (5–500 mM) further show that the inhibiting effect was overcame due to the non-radical process. Interestingly, Cl− markedly facilitated the catalytic performance by generating HOCl in the catalytic process. The results highlight leveraging the non-radical pathway dominated by singlet oxygen to conquer the inhibitory effect of anions in NGC700/PMS system, which represents a crucial step towards environmental remediation under high salinity condition.