Porous Carbon Nanocomposites Research Articles

Excellent C-band microwave absorption properties of Ni@nitrogen-doped porous carbon nanocomposite via polymer bubbling technique

Nitrogen-doped porous carbon nanocomposites are highly sought-after materials for electromagnetic wave absorption due to their unique combination of electrical and magnetic properties. However, achieving optimal absorption performance within the critical C-band (4–8 GHz) frequency range remains a significant challenge. Ni@NPC nanocomposites, synthesized through the polymer bubbling technique, demonstrated exceptional microwave absorption (MWA) performance in the C-band. These materials exhibited a reflection loss (RL) of −65.20 dB at a thickness of 4.8 mm. When carbonized at 600 °C, a thickness of 2.0 mm achieved an effective absorption bandwidth (EAB) of 5.74 GHz. The remarkable absorption performance is ascribed to the combined effect of their porous composition and the addition of nitrogen dopants, which efficiently foster various microwave attenuation processes. Furthermore, the material’s effectiveness in real-world applications was evaluated using computer simulation technology (CST). This work highlights the potential of the one-pot fabrication method for developing high-performance MWA materials with practical applications.

BaFe12O19 Functional Porous Carbon Nanocomposite as an Electrocatalyst of the Oxygen Reduction Reaction

AbstractIt is crucial to develop a non‐precious metal catalyst with high efficiency, affordable cost, and minimal environmental impact for conducting research on the oxygen reduction reaction (ORR) in fuel cells. In this study, BaFe12O19 functional porous carbon (BaFe12O19/PC) nanocomposite was successfully prepared using Fe2O3, BaCO3 and glucose as precursors. Meanwhile, the BaFe12O19/PC catalyst‐modified glassy carbon electrode, carbon rod, and Hg/HgO electrode were used as the working electrode, counter electrode, and reference electrode, respectively, to investigate the electrochemical behavior. The uniform distribution of nano‐scale BaFe12O19 particles in a porous carbon framework was confirmed by field emission scanning electron microscopy characterization. In addition, a double‐layer interface (Fe/Fe3C) was formed between the porous carbon and the nano‐sized BaFe12O19 particles. Fe/Fe3C has a synergistic effect with C, facilitating the migration and transfer of electrons from BaFe12O19 to porous carbon. The BaFe12O19/PC nanocomposite exhibited a four‐electron pathway for electrocatalytic kinetics, showcasing a significantly elevated half‐wave potential of 0.77 V, an impressively reduced Tafel slope of 84.95 mV/dec, and exceptional tolerance towards methanol. It is important to highlight that the BaFe12O19/PC nanocomposite not only possess high catalytic activity for oxygen reduction reactions (ORR), but also demonstrate excellent stability. Consequently, this synthesized BaFe12O19/PC nanocomposite hold promising prospects as cost‐effective and efficient catalysts in fuel cell applications.

Facile preparation of PtNi/Cs derived from the precipitation polymerization of a Poly(amic acid) for efficient hydrogen evolution reaction catalysis

Hydrogen evolution reaction (HER) of water is currently one of the most potential ‘green hydrogen’ production technology to alleviate the energy scarcity and environmental contamination. In this study, ultrafine platinum/nickel bimetallic nanoparticles loaded porous carbon nanocomposite, noted as PtNi/Cs, is facilely prepared by employing the precipitation polymerization of a poly (amic acid) (PAA), which shows superior catalytic performance toward HER. The synthesis of PAA is achieved via a stepwise polymerization of 4,6-diaminino-2-mercaptopyrimidine and pyromellitic dianhydride at room temperature, and the porous precursor is formed during the polymerization. Upon pyrolysis of the precursor in an inert atmosphere, carbon nanoaggregates with inherited porosity are fabricated. Ultrafine PtNi bimetallic nanoparticles with size of 3.3 ± 0.7 nm can be efficiently deposited, exhibiting an overpotential of 26.4 mV at 10 mA cm−2 and a mass activity of 2.92 A mgPt−1, superior than commercial Pt/C of 36.8 mV. The excellent HER performance can be attributed to the formation of ultrafine PtNi bimetallic nanoparticles and the electron transfer from PtNi to the nitrogen atoms on the carbon support.

Aspartic acid/ thiourea − derived N and S − doped porous carbon as a metal-free electrocatalyst for oxygen and hydrogen evolution reactions

The preparation of high-efficiency electrocatalysts for the oxygen and hydrogen evolution process (OER and HER) using an easy, green, and facile preparation method is crucial for the effective and economical use of clean energy sources. Heteroatom-doped carbon nanomaterials are effective metal-free electrocatalysts for HER and OER reactions. Herein, N and S co-doped porous carbon nanocomposite (NS-PC) was constructed as a low-cost metal-free catalyst via pyrolysis of the Thiourea and L-aspartic acid. Doping heteroatoms (N and S) into the carbon structure can induce charge redistribution, expose many active sites, accelerate charge transfer, and thus effectively improve the catalytic activity. The NS-PC electrocatalyst demonstrates proper bifunctional electrocatalytic performance for HER and OER with long-term stability in KOH electrolytes. As a result, the NS-PC requires an overpotential of 139 mV and 315 mV in the current density of 10 mA cm– 2 and the Tafel slope of 59.6 and 69.8 mV dec−1 for HER and OER, respectively. As-papered NS-PC electrocatalyst offers the development of multi-functional electrocatalysts in the water splitting process using biological substances such as amino acids.

One-pot preparation of one-dimensional hierarchically porous carbon@SnO2 nanocomposites for flexible fabric-based supercapacitor electrodes

The design of functional energy storage materials with superior performances has become the focus topic with the growing energy crisis in recent years. Herein, porous carbon nanofibers@tin dioxide (PCNFs@SnO2) composites are prepared by one-pot electrospinning and followed by carbonization. The PCNFs@SnO2 possesses a hierarchically porous structure containing mesopores and micropores. The specific surface area is as high as ∼ 559.4 m2 g−1, and the total pore volume can reach 0.28 cm3 g−1. Meanwhile, the nonwoven fabric surface is coated with a silver layer through the screen printing technique to obtain silver-coated nonwoven fabric (SNF). Importantly, PCNFs@SnO2 and SNF are combined to obtain flexible fabric-based functional materials. As a primary energy application, the prepared PCNFs@SnO2/SNF electrode has a high mass specific capacitance of 583.1 F g−1 at 1 A g−1, a high area specific capacitance of 933 mF cm−2 at 1 mA cm−2, and a good rate capability (70 % at 10 A g−1). The supercapacitor device with two PCNFs@SnO2/SNF electrodes also shows outstanding cycling durability, capacitor retention is as high as ∼ 91.52 %, after 10000 charging/discharging cycles. In brief, our study may provide an innovative route for designing hierarchically porous one-dimensional carbon nanocomposites for supercapacitors with high performances.

Novel Carbon-Coated Zirconium (IV) Oxide Nanocomposite for the Electrochemical Determination of Rutin

ZrO2 coated highly porous biomass carbon nanocomposites (ZrO2@KHPC) were synthesized by calcination. The ZrO2 was derived from an amino-functionalized metal-organic framework and the porous biomass carbon material was derived from waste sunflower products. A selective electrochemical sensor was fabricated by modifying glass carbon electrodes (GCE) using ZrO2@KHPC to determine rutin. KHPC with a porous structure exhibited strong adsorption, high specific surface area, and superior electrical conductivity, whereas ZrO2 nanoparticles with an octahedral crystal structure and high electrocatalytic activity promote the specific recognition of rutin. The ZrO2@KHPC/GCE sensor demonstrated exceptional performance with a low detection limit of 0.008 µM and a sensitivity of 28.45 µA·µΜ−1·cm−2 from 0.01 to 40 µM. This excellent performance is attributed to the synergistic combination of ZrO2 and KHPC. In addition, the electrochemical sensor demonstrated suitable stability, good selectivity, high reproducibility, and satisfactory recovery for practical analysis.

Rational design of hierarchical porous reduced graphene oxide/9,10-phenanthraquinone/porous carbon nanocomposites for high-performance supercapacitors

The development of advanced electrode material is crucial for promoting the application of new high-performance green energy storage devices and remains a great challenge. Herein, by introducing porous carbon (PC) or carbon nanotubes (CNTs) to further modify the redox-active 9,10-phenanthrenequinone (PQ) molecule non-covalently functionalized reduced graphene oxide (RGO), we have designed and synthesized RGO/PQ/PCs (RPPs) and RGO/PQ/CNTs-10 (RPC-10) nanocomposites using a simple one-step solvothermal method. Benefiting from the optimization of the hierarchical porous nanostructures and each composition further strengthens their respective advantages in the novel synthesized nanocomposites (RPPs and RPC-10), the RPPs and RPC-10 electrodes demonstrated significantly superior electrochemical energy storage performance over the RGO and RGO/PQ (RP) electrodes, especially for the RPP-10 electrode with a high specific capacitance of 343.5 F g−1 at 0.5 A g−1 and good rate capability (69.23 %, 0.5 − 40 A g−1). Furthermore, both the symmetric supercapacitor assembled with the optimal RPP-10 electrode and the hybrid supercapacitor assembled with the RPP-10 negative electrode and the NCSRC-24 positive electrode previously reported show excellent energy densities and ultra-long cycling stabilities. This result demonstrates that the synthesized novel RPP-10 nanocomposite is a highly promising candidate for new light-weight, sustainable, high-flexible and high-performance energy storage devices.

Synthesis and application of bismuth nanoparticle-loaded longan porous carbon for simultaneous electrochemical determination of Pb(II) and cd(II) in seafoods

The discarded longan shell-derived porous carbon material (LPC) served as a scaffold for synthesizing bismuth nanoparticle-loaded longan porous carbon nanocomposite (BiNPs@LPC) via a hydrothermal method. Then BiNPs@LPC was utilized to modify screen-printed carbon electrodes (SPCE) for simultaneous detection of Pb(II) and Cd(II) by square wave anodic stripping voltammetry (SWASV). The material was thoroughly characterized by scanning electron microscopy, X-ray diffraction, Raman spectra, Brunauer-Emmett-Teller analysis, electrochemical impedance spectroscopy and cyclic voltammetry. BiNPs@LPC exhibited abundant porous structures, high surface area, and numerous active sites, which could improve significantly response sensitivity. Under optimal conditions, the peak currents of Pb(II) and Cd(II) exhibited favorable linear relationships with the concentration within a range of 0.1–150 μg L−1, with detection limits (S/N = 3) of 0.02 μg L−1 and 0.03 μg L−1, respectively. BiNPs@LPC/SPCE demonstrated remarkable selectivity, stability and repeatability. The proposed method was successfully applied for the detection of Pb(II) and Cd(II) in seafoods achieving satisfying recovery of 97.8%–108.3% and 96.7%–106.4%. These excellent test properties were coupled with convenience for batch preparation of the modified electrodes, highlighting its potential for practical applications in heavy metal detection of real samples.

Manipulating cellulose-based dual-network coordination for enhanced electromagnetic wave absorption in magnetic porous carbon nanocomposites

A novel dual-network coordination strategy was utilized to prepare carbon based magnetic porous EMW absorption nanocomposites with controllable magnetic particles deposition on carbon matrices. Due to the conversion of carboxymethyl cellulose (CMC) into Prussian blue (PB) through coordination with Fe3+, the deposition of Fe3+ gradually tends to aggregate. Consequently, significant changes occur in the polycrystalline structure of magnetic Fe3O4 particles in the pyrolysis products, including alterations in grain size, orientation, and the overall size of polycrystalline particle. Finally, the obtained Fe3O4 decorated porous carbon nanocomposites showed ultrawide effective absorption band of 6.7 GHz owing to the advantageous impedance matching and the synergistic dielectric and magnetic loss effects. Overall, this study offers valuable insights into the design and comprehension of magnetic porous nanocomposites for efficient EMW absorption through the regulation of polycrystalline structure by controllable coordination deposition.

Ni, Co-Embedded MOF-Derived N-Doped Bimetallic Porous Carbon for Adsorption-Photocatalytic Degradation of Organic Dyes and Antibiotics.

An efficient protocol for photocatalytic degradation of organic dyes and antibiotics has been successfully established via MOF-derived (MOF = metal-organic framework) Ni, Co-embedded N-doped bimetallic porous carbon nanocomposites (NiCo/NC). Such a NiCo/NC nanocomposite features well-distributed structures, suitable specific surface areas, and more active sites determined by various characterization analyses. The catalyst exhibits higher photocatalytic performance and stability toward the liquid-phase degradation of methylene blue (MB) under visible light irradiation for 60 min, after the adsorption-desorption equilibrium and the thorough degradation into H2O and CO2. Radical quenching experiments further confirmed the dominant effect of electron holes h+ and superoxide radical anions ·O2- for the MB photodegradation process. NiCo/NC was also appropriate for the degradation of Rhodamine B, methyl orange, tetracycline hydrochloride, and norfloxacin. Moreover, NiCo/NC is robust, and its photocatalytic activity is basically maintained after 8 cycles. This work is expected to provide additional information for the design of MOF-derived carbon material with more excellent properties and lay the foundation for further industrial applications.

N-doped porous carbon modified by polyacrylic acid for efficient removal of disinfection products in environmental waters under extensive conditions

In this work, a novel porous carbon nanocomposite was successfully prepared by creatively using polyacrylic acid to modify N-doped porous carbon, which was used to adsorb and remove new cyclic chlorine disinfection by-products in various water environments. The high-temperature calcination process at 1000 °C created a hierarchical pore structure that contained both micropores and mesopores. This structure significantly increased the mass transfer efficiency of the target on the adsorbent. The incorporation of N atoms enhanced NC's binding affinity and furnished target adsorption sites. The dispersion of N-doped porous carbon was significantly improved after polyacrylic acid modification. Moreover, the surface charge of NC-1000 was also altered, facilitating easier electrostatic interaction with DBPs. Subsequently, faster adsorption kinetics was obtained within 2 min, and the removal efficiency of 2,4-dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP) were promoted to 94.10 % and 98.71 %, respectively. Characterization and data analysis revealed that the primary adsorption mechanism was chemical (electrostatic interaction, hydrophobic interaction, π-π interaction, and hydrogen bond). Surprisingly, factors such as ionic strength, natural organic matter and pH had minimal impact on the adsorption process, indicating that NC-1000@PAA had excellent anti-interference performance. Despite undergoing four adsorption–desorption cycles, NC-1000@PAA upheld a steady composition along with a remarkable adsorption capability. Furthermore, NC-1000@PAA had negligible cytotoxicity, which was assessed by cell experiments. The application of NC-1000@PAA was attested in various environmental waters. The proposed method provided a new strategy to pollutant removal by NC-1000@PAA under extensive conditions, which had wide perspective and practicability on the purification treatment of environmental water.

Dual-mode detection of antibiotic drugs using ytterbium molybdate/porous carbon nanocomposite

Monitoring the levels of metronidazole (MTZ) is crucial to ensure the desired therapeutic effectiveness and to prevent potential harm to patients. However, MTZ exhibits concentration-dependent antimicrobial activity and has a narrow therapeutic range. In this study, “one stone two mango” strategy was influenced for the electrochemical and UV–vis spectroscopy detection of antibiotic residues of MTZ. The successfully synthesized ytterbium molybdate nano petals (YbMO) with porous carbon (PC) nanocomposite (NC) using ultrasonication method. The YbMO/PC NC, as well as other modified electrodes, were identified and targeted as molecules using natural pH as the probe to indicate current intensity. Also, examined the morphology and physicochemical properties of the synthesized materials. Furthermore, conducted cycling voltammetry (CV) and linear sweep voltammetry (LSV) on the modified electrodes to model MTZ analytes. Among them, the YbMO/PC NC/GCE exhibited larger reduction peak current and lower potential compared to other modified electrodes due to the synergistic effect between YbMO and PC, resulting in effective detection of MTZ. The YbMO/PC NC/GCE demonstrated exceptional sensitivity (3.28 µA µM−1 cm−2), a wide linear range (0.01–10.61 and 20.61–1630.61 µM), and a remarkably low detection limit (LOD: 0.006 µM). The proposed YbMO/PC NC/GCE exhibits the successfully analyzed MTZ in serum (101%), urine (97.9%), tablets (99.15%), lake (99.1%), and river water (99.8%). On the other hand, a UV–vis spectrometric method was employed to detect MTZ. The results showed a wide linear range (0.05–57.2 µM) and an impressive LOD (70 nM). These results are attributed to the heightened sensitivity, selectivity, repeatability, and durability of the sensor.

The Use of Magnetic Porous Carbon Nanocomposites for the Elimination of Organic Pollutants from Wastewater

One of the most significant challenges the world is currently facing is wastewater treatment. A substantial volume of effluents from diverse sources releases numerous pollutants into the water. Among these contaminants, organic pollutants are particularly concerning due to the associated risk of being released into the environment, garnering significant attention. Rapid advancements in agriculture and industry on a global scale generate vast volumes of hazardous organic compounds, which eventually find their way into natural systems. Recently, the release of industrial wastewater has been increasing, due to the progress of numerous businesses. This poses a danger to humans and the environment, leading to environmental contamination. The application of carbon nanocomposites in applied nanotechnology has recently expanded due to their large surface area, substantial pore volume, low preparation cost, and environmental resilience. Expanding the use of nanomaterials in water treatment is essential, as magnetic carbon nanocomposites consistently demonstrate an efficient elimination of pollutants from water solutions. In the current study, we have highlighted the application of magnetic porous carbon nanocomposites in removing organic pollutants from wastewater.

Monolithic metal-based/porous carbon nanocomposites made from dissolved cellulose for use in electrochemical capacitor

Porous metal-based carbon nanocomposites, with a monolithic shape, were prepared by a one-pot synthesis from dissolved cellulose and metallic salts using a simple, cheap, and environmentally friendly route. Their potential performances as electrochemical capacitors were tested with three metal precursors (M = Cu, Mn, and Fe) with two loadings and in an asymmetric cell for the Fe-based carbon material. Interestingly, here soluble metal precursors were not deposited on a hard cellulose template but mixed in a precooled concentrated NaOH solution where cellulose was previously dissolved, allowing for a good dispersion of the metallic species. After a freezing step where concomitant cellulose regeneration and pore ice-templating phenomena took place, followed by a carbonization step, the mixture led to a porous carbon monolith embedding well-dispersed metal-based nanoparticles having a diameter below 20 nm and present as metallic, oxide, or carbide phase(s) according to the element M. These materials were characterized by different physicochemical techniques and electrochemical tests. Their performances as supercapacitors are discussed in light of the specific behaviour of the metal-based phase and its influence on the carbon matrix properties such as mesopore formation and carbon graphitization. An asymmetric energy storage cell assembled with a Fe-based carbon electrode against a carbon xerogel electrode derived from a phenolic resin shows specific energy and power of 18.3 Wh kg−1 at 5 mA cm−2 and 1.6 kW kg−1 at 25 mA cm−2, respectively.

Preparation of rod-zinc oxide/agaric derived porous carbon nanocomposites and their application in electrochemical sensing

The porous carbon material prepared from agaric biomass was combined with zinc oxide nanorods to obtain an electrochemical sensor, which could be used to detect PA, DA and luteolin.

Enzymolytic Lignin-Derived N-S Codoped Porous Carbon Nanocomposites as Electrocatalysts for Oxygen Reduction Reactions.

Currently, the development of nonmetallic oxygen reduction reaction (ORR) catalysts based on heteroatomic-doped carbon materials is receiving increaseing attention in the field of fuel cells. Here, we used enzymolytic lignin (EL), melamine, and thiourea as carbon, nitrogen, and sulfur sources and NH4Cl as an activator to prepare N- and S-codoped lignin-based polyporous carbon (ELC) by one-step pyrolysis. The prepared lignin-derived biocarbon material (ELC-1-900) possessed a high specific surface area (844 m2 g-1), abundant mesoporous structure, and a large pore volume (0.587 cm3 g-1). The XPS results showed that ELC-1-900 was successfully doped with N and S. ELC-1-900 exhibited extremely high activity and stability in alkaline media for the ORR, with a half-wave potential (E1/2 = 0.88 V) and starting potential (Eonset = 0.98 V) superior to those of Pt/C catalysts and most non-noble-metal catalysts reported in recent studies. In addition, ELC-1-900 showed better ORR stability and methanol tolerance in alkaline media than commercial Pt/C catalysts.

Facile preparation of Ni@C/hierarchically porous carbon nanocomposites with excellent electrochemical performance from Ni-MOF/porous polymers

High performance supercapacitors are significant for the practical application of the novel renewable energies. Comparisons suggest that hybrid supercapacitor (HSC) is a fairly promising type for application since it combines high power density and high energy density. In this study, hierarchically porous carbons (HPCs) supported Ni@C nanoparticles (Ni@C/HPCs) were obtained by pyrolyzing the precursors of Ni-based MOF/porous polymers (Ni-MOF/polyHIPEs) which were prepared by high internal phase emulsion (HIPE) polymerization followed with solvothermal Ni-MOF growing. The composition and morphology of the Ni@C/HPCs can be controlled by changing the growth time of Ni-MOF. The optimized sample Ni@C/HPC-15 demonstrates a high specific capacity of 215.0 C g−1 at 1 A g−1 and a high rate performance of 82.3% when the current density increases from 1 A g−1 to 10 A g−1. Furthermore, Ni@C/HPC//HPC HSC was assembled and achieved an energy density of 40.9 Wh kg−1 at a power density of 747.2 W kg−1. In particular, the assembled HSC exhibited a remarkable initial capacitance retention of 86.3% after 5000 cycles at 6 A g−1. The reported convenient method may provide inspiration in the preparation and optimization of HPC-based electrode materials with satisfactory performances for energy storage.

Macro-ordered porous carbon nanocomposites for efficient microwave absorption

Tunable and efficient porous carbon-based microwave absorbers are essential in electromagnetic compatibility and protection due to their pronounced dielectric losses and ultralow density. However, it is still challenging to achieve satisfactory impedance matching and attenuation ability owing to the difficulty of realizing custom-designed porous structures. Herein, we propose a material-structure collaborative approach which includes multi-scaling, component modulation and systematic investigation of macroscopic structures. Macro-ordered porous carbon nanocomposites (MOPCN) assembled with MWCNTs and chitosan (CHI) were fabricated via freeze casting and MWCNTs/CHI ratio regulation. By simply varying the freezing temperature gradient distribution from radial (R) to axial (A), radial-centrosymmetric and honeycomb-like pore arrays were realized respectively. Compared with the honeycomb-like pore array, the radial-centrosymmetric pore array imparts much stronger microwave attenuation capability due to enhanced phase contiguity and optimized spatial arrangement. Such configuration also enabled one to optimize impedance matching and absorption, alleviating the over-dependence of microwave absorption performance on material composition. Optimum absorption of up to −70.6 dB at 9.3 GHz and −72.9 dB at 8.8 GHz were achieved for the MOPCN-1/4-R and MOPCN-1/2-A composites, respectively, with effective absorption band covering the entire X-band at a low filler loading of 1 wt%. Overall, this study provides a further understanding of the structure-property relationship and paves the way for future exploration of plainified microwave absorbers based on optimized macropore structures while preserving low filler loading.

Electromagnetic wave absorption properties of porous carbon nanocomposite prepared by explosion method derived from energetic CuFe-MOF

An energetic heteronuclear metal–organic framework (MOF), denoted as {[CuIIFeIII3O(tza)6(H2O)3]·Cl·(NO3)2·4H2O}n (CuFe-MOF), was successfully synthesized and characterized using various techniques, including single-crystal X-ray diffractometry (XRD), powder X-ray diffractometry (PXRD), and scanning/transmission electron microscopy (SEM/TEM). The compound crystallized in the P63m space group, forming an infinite 3D cationic network composed of [Fe3O(tza)6]+ clusters and Cu2+ ions. Subsequently, we transformed CuFe-MOF into porous carbon nanocomposites, C/Cu/Fe3N/Fe4N/Fe3O4/CuFe2O4, using an explosion method. We then investigated the electromagnetic wave (EMW) attenuation properties and mechanisms of the carbon nanocomposite. Notably, the synthesized C/Cu/Fe3N/Fe4N/Fe3O4/CuFe2O4 composite material demonstrated exceptional EMW absorption. At a low frequency of 4.1 GHz with a thickness of 5.0 mm, it achieved a minimum reflection loss (RL) of −47.7 dB. Even at a high frequency of 17.8 GHz and a thickness of 1.5 mm, the minimum RL reached −41.8 dB. Moreover, this material exhibited a wide effective absorption bandwidth (EAB; RL ≤ −10 dB) spanning 14.9 GHz (3.1–18 GHz) for thicknesses between 1.0 and 5.5 mm. These attributes position the carbon composite as a strong candidate for absorption applications within the Ku, X, and C bands, making it suitable for both military and civilian usage. Our mechanistic analysis suggests that the excellent absorption performance of C/Cu/Fe3N/Fe4N/Fe3O4/CuFe2O4 results from a combination of mechanisms, including electrical and magnetic loss. This research introduces an innovative approach for the fabrication of high-performance carbon composite materials via the explosive method, utilizing multinuclear energetic materials.

Preparation of size-tunable Fe3O4 magnetic nanoporous carbon composites by MOF pyrolysis regulation for magnetic resonance sensing of aflatoxin B1 with excellent anti-matrix effect

Magnetic nanoporous materials represent a new emerging category of magnetic materials for construction of magnetic resonance sensors. In this study, we adopted the metal–organic framework materials, MIL-101(Fe), as the precursor to prepare series nanoporous-carbon-Fe3O4 (NPC-Fe3O4) composites. Results showed that Fe3O4 were uniformly distributed in MIL-101(Fe) and the size of MNP was precisely tuned at different pyrolysis temperatures, conferring the optimal NPC-Fe3O4-450 °C composite with dramatically improved T2 relaxivity. The NPC-Fe3O4-450 °C composite was modified with antibodies and antigens, respectively, for detection of aflatoxin B1 in various food samples with complicated matrix. Range from 0.010 ng mL−1 to 2.0 ng mL−1, extreme low detection limit of 5.0 pg mL−1, and satisfied recoveries were successfully achieved, indicating excellent anti-matrix effect. These findings offer a new dimension to engineer novel magnetic materials with improved relaxivity for simple and easy sensing of food hazards in complicated food matrix without any purification or separation procedures.