Mesoporous Carbon Materials with Functional Compositions

Degradation of Bisphenol A by Nitrogen-Rich ZIF-8-Derived Carbon Materials-Activated Peroxymonosulfate

Bisphenol A (BPA), representing a class of organic pollutants, finds extensive applications in the pharmaceutical industry. However, its widespread use poses a significant hazard to both ecosystem integrity and human health. Advanced oxidation processes (AOPs) based on peroxymonosulfate (PMS) via heterogeneous catalysts are frequently proposed for treating persistent pollutants. In this study, the degradation performance of BPA in an oxidation system of PMS activated by transition metal sites anchored nitrogen-doped carbonaceous substrate (M-N-C) materials was investigated. As heterogeneous catalysts targeting the activation of peroxymonosulfate (PMS), M-N-C materials emerge as promising contenders poised to overcome the limitations encountered with traditional carbon materials, which often exhibit insufficient activity in the PMS activation process. Nevertheless, the amalgamation of metal sites during the synthesis process presents a formidable challenge to the structural design of M-N-C. Herein, employing ZIF-8 as the precursor of carbonaceous support, metal ions can readily penetrate the cage structure of the substrate, and the N-rich linkers serve as effective ligands for anchoring metal cations, thereby overcoming the awkward limitation. The research results of this study indicate BPA in water matrix can be effectively removed in the M-N-C/PMS system, in which the obtained nitrogen-rich ZIF-8-derived Cu-N-C presented excellent activity and stability on the PMS activation, as well as the outstanding resistance towards the variation of environmental factors. Moreover, the biological toxicity of BPA and its degradation intermediates were investigated via the Toxicity Estimation Software Tool (T.E.S.T.) based on the ECOSAR system.

A Multichannel Screen-Printed Carbon Electrode Based on Fluorinated Poly(3-octylthiophene-2,5-diyl) and Purified Mesoporous Carbon Black Simultaneously Detects Na+, K+, Ca2+, and NO2. ACS OMEGA 2024;9:18238-18248. [PMID: 38680364 PMCID: PMC11044230 DOI: 10.1021/acsomega.3c10471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Preparation of nanocomposites based on fluorinated poly(3-octylthiophene-2,5-diyl) (POTF) and purified mesoporous carbon black (PMCB) as the solid-contact layer of a screen-printed carbon electrode (SPCE) is proposed. POTF is used as a dispersant for PMCB. The obtained nanocomposites possess unique characteristics including high conductivity, capacitance, and stability. The SPCE based on POTF and PMCB is characterized by electrochemical impedance spectroscopy and chronopotentiometry, demonstrating simultaneous detection of Na+, K+, Ca2+, and NO2- ions with detection limits of 10-6.5, 10-6.4, 10-6.7, and 10-6.3 M, respectively. Water layer and anti-interference tests revealed that the electrode has high hydrophobicity, and the static contact angle is >140°. The electrode shows excellent selectivity, repeatability, reproducibility, and stability and is not easily affected by light, O2, or CO2.

Carbon Surface Chemistry: New Insight into the Old Story

The enormous complexity of the carbon material family has provoked a phenomenological approach to develop its potential in different applications. Although the electronic, chemical, mechanical, and magnetic properties of carbon materials have been widely discussed based on defect control engineering, there is still a lack of fundamental understanding of the carbon surface chemistry, which leads to many controversial conclusions. Here, by analyzing various defects on carbon surface, some commonly neglected aspects and misunderstandings in this field are pointed out, clarifying how surface chemistry affects the chemical behaviors of carbon in some specific chemical reactions. With this full-scale consideration of the carbon surface chemistry, the behaviors of carbon materials with various functions can be well defined, which is indispensable for their scalable applications. Perspectives on future developments of carbon surface chemistry are also provided to enable practically accessible design of advanced carbon in those applications.

Recent Advances on Heteroatom-Doped Porous Carbon/Metal Materials: Fascinating Heterogeneous Catalysts for Organic Transformations

Design and preparation of low-cost, effective, and novel catalysts are important topics in the field of heterogeneous catalysis from academic and industrial perspectives. Recently, heteroatom-doped porous carbon/metal materials have received significant attention as promising catalysts in divergent organic reactions. Incorporation of heteroatom into the carbon framework can tailor the properties of carbon, providing suitable interaction between support and metal, resulting in superior catalytic performance compared with those of traditional pure carbon/metal catalytic systems. In this review, we try to underscore the recent advances in the design, preparation, and application of heteroatom-doped porous carbon/metal catalysts towards various organic transformations.

Rapid access to ordered mesoporous carbons for chemical hydrogen storage

Ordered mesoporous carbon materials offer robust network of organized pores for energy storage and catalysis applications, but suffer from time-consuming and intricate preparations hindering their widespread use. Here we report a new and rapid synthetic route for a N-doped ordered mesoporous carbon structure through a preferential heating of iron oxide nanoparticles by microwaves. A nanoporous covalent organic polymer is first formed in situ covering the hard templates of assembled nanoparticles, paving the way for a long-range order in a carbonaceous nanocomposite precursor. Upon removal of the template, a well-defined cubic mesoporous carbon structure was revealed. The ordered mesoporous carbon was used in solid state hydrogen storage as a host scaffold for NaAlH 4 , where remarkable improvement in hydrogen desorption kinetics was observed. The state-of-the-art lowest activation energy of dehydrogenation as single step was attributed to their ordered pore structure and N-doping effect.

Recent advances in metal-free heteroatom-doped carbon heterogonous catalysts

The development of cost-effective, efficient, and novel catalytic systems is always an important topic for heterogeneous catalysis from academia and industrial points of view. Heteroatom-doped carbon materials have gained more and more attention as effective heterogeneous catalysts to replace metal-based catalysts, because of their excellent physicochemical properties, outstanding structure characteristics, environmental compatibility, low cost, inexhaustible resources, and low energy consumption. Doping of heteroatoms can tailor the properties of carbons for different utilizations of interest. In comparison to pure carbon catalysts, these catalysts demonstrate superior catalytic activity in many organic reactions. This review highlights the most recent progress in synthetic strategies to fabricate metal-free heteroatom-doped carbon catalysts including single and multiple heteroatom-doped carbons and the catalytic applications of these fascinating materials in various organic transformations such as oxidation, hydrogenation, hydrochlorination, dehydrogenation, etc.

Removal of ammonia nitrogen from water by mesoporous carbon electrode-based membrane capacitance deionization

The removal of ammonia nitrogen from wastewater is always a focus in current water treatment. In this study, a combination of mesoporous carbon electrode and selective ion exchange membrane was used to assemble a membrane capacitor deionization system (MCDI). The optimal process parameters were determined as follows: the plate spacing was 1 mm, the voltage was 1.2 V, and the flow rate was 23.8 mL/min. Under the optimal conditions, the removal efficiency of ammonia nitrogen can reach more than 80%. The quasi-first order kinetics and Langmuir adsorption isotherm model can well describe the adsorption process of MCDI. The nature of physical adsorption between ammonia nitrogen cations and mesoporous carbon electrode was demonstrated by the calculation of activation energy and thermodynamic parameters. Moreover, 1500 mg/L NH₄Cl, NaNO₂, and NaNO₃ solutions were tested respectively. The results showed that the removal efficiencies of NH₄⁺, NO₂^-, and NO₃^- were 82.33%, 90.96%, and 97.73% respectively, indicating that MCDI is feasible to removal different forms of inorganic nitrogen from water.

Three-Dimensional Cubic and Dice-Like Microstructures of Higher Fullerene C78 with Enhanced Photoelectrochemical and Photoluminescence Properties

The single-crystal micro/nanostructures of fullerene species, namely C₆₀ and C₇₀ , have been previously studied, but studies on the morphology and properties of higher fullerenes have rarely been reported due to the limited amount of samples and their ellipsoidal isomeric structures. Herein, we report the formation of three-dimensional (3D) micro-cubes and micro-dice of a higher fullerene (C₇₈ ) via a facile liquid-liquid interfacial precipitation (LLIP) method. The micro-cubes were prepared by regulating the concentration of C₇₈ in trimethylbenzene (TMB) and the volume ratio of TMB and isopropanol. Interestingly, the micro-cubes are transformed into micro-dice with an open-hole on each crystal face by simply shaking the solution. X-ray diffraction and Fourier-transform infrared spectroscopic studies revealed a simple cubic unit cell with a lattice constant of 10.6 Å and intercalated TMB molecules in both crystals. The C₇₈ cubic and dice-like microstructures exhibited enhanced photoelectrochemical and photoluminescence properties compared with pristine C₇₈ powder, indicating their potential applications as photodetectors and photoelectric devices.

Covalent organic frameworks (COFs) for electrochemical applications

Covalent organic frameworks are a class of extended crystalline organic materials that possess unique architectures with high surface areas and tuneable pore sizes. Since the first discovery of the topological frameworks in 2005, COFs have been applied as promising materials in diverse areas such as separation and purification, sensing or catalysis. Considering the need for renewable and clean energy production, many research efforts have recently focused on the application of porous materials for electrochemical energy storage and conversion. In this respect, considerable efforts have been devoted to the design and synthesis of COF-based materials for electrochemical applications, including electrodes and membranes for fuel cells, supercapacitors and batteries. This review article highlights the design principles and strategies for the synthesis of COFs with a special focus on their potential for electrochemical applications. Recently suggested hybrid COF materials or COFs with hierarchical porosity will be discussed, which can alleviate the most challenging drawback of COFs for these applications. Finally, the major challenges and future trends of COF materials in electrochemical applications are outlined.

Facile Synthesis of Size-Controlled Nitrogen-Doped Mesoporous Carbon Nanosphere Supported Ultrafine Ru Nanoparticles for Selective Hydrogenation of Quinolines

Nitrogen-doped mesoporous carbon nanosphere (NMCS) with tunable sizes and uniform mesoporosity was synthesized by a facile soft-templating method. During the synthesis, F127 (PEO-PPO-PEO triblock copolymer) could be used not only as a soft template to generate the mesostructure but also as a size-control agent to tailor the size of NMCS in a relatively wide range of 100 to 700 nm. In addition, the synthesis process was simple and suitable for large-scale production. Moreover, the NMCS was used as support of ultrafine Ru nanoparticles (Ru/NMCS), which exhibited good catalytic performances for selective hydrogenation of quinolones. It is expected that the simple synthetic strategy for the NMCS can generate extensive interest in many catalysis and sorption applications.

Oxidation modification of chitosan-based mesoporous carbon by soft template method and the adsorption and release properties of hydroxycamptothecin

Spray drying and a direct carbonization technology were coupled to prepare nitrogen-doped mesoporous carbon nanoparticles (NMCs) using chitosan as a carbon source and nitrogen source precursor and a triblock amphiphilic copolymer (F127) as a soft template, then oxidative modification was performed by ammonium persulfate (APS) to prepare oxidized mesoporous carbon nanoparticles (O-NMCs). The pore structure, chemical composition and wettability of the mesoporous materials were studied before and after oxidative modification, the microscopic morphology, structure, composition and wetting performance of the mesoporous carbon were characterized by transmission electron microscopy (TEM), an X-ray diffractometer (XRD), N₂ adsorption–desorption instrument, X-ray photoelectron spectroscopy (XPS), contact angle tests and other analyses, meanwhile influences of the mesoporous carbon material on adsorption and release performance of a poorly-soluble antitumor drug hydroxycamptothecin (HCPT) were investigated. It was demonstrated from results that the surface wettability of the oxidatively-modified mesoporous carbon material was improved, the contact angle of the mesoporous carbon materials was reduced from 133.4° to 58.2° and the saturated adsorption capacity of HCPT was 676.97 mg/g and 647.20 mg/g respectively. The dissolution rate of the raw material hydroxycamptothecin was improved due to the nanopore structure of the mesoporous carbon material, the dissolution rate of mesoporous carbon material-loaded hydroxycamptothecin was increased from 22.7% to respective 83.40% and 81.11%.

Direct Synthesis of Microporous Bicarbazole-Based Covalent Triazine Frameworks for High-Performance Energy Storage and Carbon Dioxide Uptake

In this study a series of bicarbazole-based covalent triazine frameworks (Car-CTFs) were synthesized under ionothermal conditions from [9,9'-bicarbazole]-3,3',6,6'-tetracarbonitrile (Car-4CN) in the presence of molten zinc chloride. Thermogravimetric and Brunauer-Emmett-Teller analyses revealed that these Car-CTFs possessed excellent thermal stabilities and high specific surface areas (ca. 1400 m² /g). The electrochemical performances of this Car-CTF series, investigated by using cyclic voltammetry, showed a highest capacitance of (545 F/g at 5 mV/s), which also exhibited excellent columbic efficiencies of 96.1 % after 8000 cycles at 100 μA/0.5 cm² . The other Car-CTF samples displayed similar efficiencies. Furthermore, based on CO₂ uptake measurements, one of the series showed the highest CO₂ uptake capacities: 3.91 and 7.60 mmol/g at 298 and 273 K, respectively. These results suggest a simple method for the preparation of CTF materials that provide excellent electrochemical and CO₂ uptake performance.

Facile one-pot solvothermal synthesis of magnetic mesoporous carbon for the efficient adsorption of methyl orange

A facile one-pot solvent thermal method was proposed to synthesize magnetic mesoporous carbon (MMC) using Fe(NO₃)₃·9H₂O as a precursor, Pluronic copolymer P123 as template, and chitosan as carbon source, and it was applied for the adsorptive remediation of methyl orange (MO). The characterization results of TEM, XRD, and IR showed that MMC consisted of graphitized carbon matrix and some black spherical particle mixture of Fe₃O₄ and Fe, and it was rich in hydroxyl and carbonyl groups. Besides, the effect of the content of Fe and the content of chitosan in MMC on the magnetism and adsorption performance of prepared material were investigated. In addition, the effects of pH value, initial concentration of methyl orange, and contact time on the adsorption performance of MO were studied, respectively. At 318 K, the maximum adsorption capacity of MO calculated from Langmuir isotherm was from 139 to 400 mg g^-1 on MMC. Kinetic studies demonstrated that the adsorption process obeyed a pseudo-second-order kinetic model. The regeneration experiments revealed that MMC could be reused at least five times without notable decrease of adsorption performance. These results illustrate that MMC is an efficient and economical adsorbent for the adsorption of MO.

Ultrastable conductive microporous covalent triazine frameworks based on pyrene moieties provide high-performance CO2 uptake and supercapacitance

Two pyrene-functionalized CTFs through ionothermal treatment TCNPy in the presence of molten zinc chloride at 500 °C, which displayed high-performance CO₂ uptake and supercapacitance.

Ultrahigh Surface Area N-Doped Hierarchically Porous Carbon for Enhanced CO2 Capture and Electrochemical Energy Storage

Facile synthesis of ultrahigh surface area porous carbons with well-defined functionalities such as N-doping remains a formidable challenge as extensive pore creation results in significant damage to the active sites. Herein, an ultrahigh surface area, N-doped hierarchically porous carbon was prepared through a multicomponent co-assembly approach. The resultant N-doped hierarchically porous carbon (N-HPC) possessed an ultrahigh surface area (≈1960 m²  g^-1 ), a uniform interpenetrating micropore (≈1.3 nm) and large mesopore (≈7.6 nm) size, and high N-doping in the carbon frameworks (≈5 wt %). The N-HPC exhibited a high specific capacitance (358 F g^-1 at 0.5 A g^-1 ) as a supercapacitor electrode in aqueous alkaline electrolyte with a stable cycling performance after10 000 charge/discharge cycles. Moreover, as a CO₂ absorbent, N-HPC displayed an adsorption capacity of 29.0 mmol g^-1 at 0 °C under a high pressure of 30 bar.

Acetylcholinesterase Biosensor Based On Mesoporous Hollow Carbon Spheres/Core-Shell Magnetic Nanoparticles-Modified Electrode for the Detection of Organophosphorus Pesticides

The present study investigated the synthesis of mesoporous hollow carbon spheres (MHCS) and magnetic mesoporous hollow carbon spheres with core-shell structures (Fe₃O₄@MHCS). Two acetylcholinesterase sensors (acetylcholinesterase/mesoporous hollow carbon spheres/glassy carbon electrode (AChE/MHCS/GCE) and acetylcholinesterase/core-shell magnetic mesoporous hollow carbon spheres/glassy carbon electrode (AChE/Fe₃O₄@MHCS/GCE) based on mesoporous carbon materials were prepared. Under the optimum conditions, using Malathion as the model compound, the developed biosensors showed a wide detection range, low detection limit, good reproducibility, and high stability. The AChE/MHCS/GCE electrochemical sensor response exhibited two good linear ranges at the incubation time of 10 min at the Malathion concentration ranges of 0.01 to 100 ppb and 100 to 600 ppb, with a detection limit of 0.0148 ppb (S/N = 3). The AChE/Fe₃O₄@MHCS/GCE electrochemical sensor that was operated with an incubation time of 12 min at the malathion concentration ranges between 0.01–50 ppb and 50–600 ppb had a detection limit of 0.0182 ppb (S/N = 3). Moreover, the AChE/MHCS/GCE and AChE/Fe₃O₄@MHCS/GCE biosensors were effective for the detection of real samples, and were demonstrated to be suitable for the field-testing of organophosphorus pesticide (OP) residues.

Immunotoxicity assessment of ordered mesoporous carbon nanoparticles modified with PVP/PEG

With large surface area and three-dimensional pore structure, mesoporous carbon nanoparticles (MCN) have attracted enormous interests as potential drug carriers. However, MCN immunotoxicity has not been clarified clearly up to now. Herein we reported the effect of MCN with and without PVP or DSPE mPEG2000 (PEG) modification on immune cells including dendritic cells (DCs), T lymphocytes and RAW264.7 macrophages in vitro. Furthermore, blood biochemical tests, alexin C3 assay and histological analysis were used to investigate the toxicity of MCN in vivo. The synthesized MCN with average particle size about 90 nm was naturally insoluble in water. Surface modification with PVP (MCN-PVP) or PEG (MCN-PEG) slightly increased the particle size and Zeta potential, and effectively improved the dispersion of mesoporous carbon. MCN, MCN-PVP and MCN-PEG promoted the differentiation and maturation of the DCs, while the levels of secreted TNF-α and IL-6 were significantly suppressed by MCN-PVP and MCN-PEG. These materials significantly induced apoptosis of T lymphocytes. The histopathologic results showed that there was no significant difference between nanoparticles with or without modification. Importantly, the materials deposition was observed in the lung, which could potentially inhibit lung metastasis. In conclusion, the ordered mesoporous carbon nanoparticles superficially modified by PVP or PEG perform well in immunological biocompatibility, and are likely to be a promising candidate as medicine carrier in pharmaceutics and clinic.