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Abstract C–H bond activation enables the facile synthesis of new chemicals. While C–H activation in short-chain alkanes has been widely investigated, it remains largely unexplored for long-chain organic molecules. Here, we report light-driven C–H activation in complex organic materials mediated by 2D transition metal dichalcogenides (TMDCs) and the resultant solid-state synthesis of luminescent carbon dots in a spatially-resolved fashion. We unravel the efficient H adsorption and a lowered energy barrier of C–C coupling mediated by 2D TMDCs to promote C–H activation and carbon dots synthesis. Our results shed light on 2D materials for C–H activation in organic compounds for applications in organic chemistry, environmental remediation, and photonic materials.

Layered double hydroxide (LDH) is considered a highly promising electrode material for supercapacitors (SCs) due to its high theoretical specific capacitance. However, LDH powders often suffer from poor electrical conductivity, structure pulverization, slow charge transport, and insufficient active sites. Herein, a self‐supporting electrode with a Mott–Schottky heterostructure has been designed for high‐performance SCs. The electrode consists of low crystallinity NiCo‐LDH nanosheets and vertical graphene (VG) directly grown on carbon cloth. The LDH was converted from a metal–organic framework (MOF) by the sol–gel method. This self‐supporting electrode provides fast charge transfer, reducing the pulverization effect and energy barrier. The Mott–Schottky heterostructure of LDH@VG regulates electron density and enhances electron transfer, as confirmed by density functional theory calculation. The optimized LDH@VG heterostructure electrode exhibits an excellent areal capacitance of 5513.8 mF cm−2 and rate capability of 82.1%. Furthermore, the fabricated hybrid SC demonstrates excellent energy density of 404.8 μWh cm−2 at 1.6 mW cm−2 and a remarkable cycling life, with a capacitance of 92.0% after 10 000 cycles. This work not only provides a simple dip‐coating and MOF conversion method to synthesize heterojunction‐based electrodes, but also broadens the horizon for designing advanced electrode materials for SCs.

Abstract Point defects in two-dimensional materials are of key interest for quantum information science. However, the parameter space of possible defects is immense, making the identification of high-performance quantum defects very challenging. Here, we perform high-throughput (HT) first-principles computational screening to search for promising quantum defects within WS2, which present localized levels in the band gap that can lead to bright optical transitions in the visible or telecom regime. Our computed database spans more than 700 charged defects formed through substitution on the tungsten or sulfur site. We found that sulfur substitutions enable the most promising quantum defects. We computationally identify the neutral cobalt substitution to sulfur ( $${\rm{Co}}_{{{{{{{{\rm{S}}}}}}}}}^{0}$$ Co S 0 ) and fabricate it with scanning tunneling microscopy (STM). The $${\rm{Co}}_{{{{{{{{\rm{S}}}}}}}}}^{0}$$ Co S 0 electronic structure measured by STM agrees with first principles and showcases an attractive quantum defect. Our work shows how HT computational screening and nanoscale synthesis routes can be combined to design promising quantum defects.

The research on two-dimensional materials has gained significant traction due to their potential for thermoelectric, optical, and other properties. The development of two-dimensional (2D) nanostructured-based TE generators and photodetectors has shown promising results. Over the years, researchers have played a crucial role in advancing this field, enhancing the properties of 2D materials through techniques such as doping, alloying, and various growth methods. Among these materials, black phosphorus, transition metal dichalcogenides, graphene, and IVA-VIA compounds stand out for their remarkable electronic, mechanical, and optical properties. This study presents a comprehensive review of the progress in the field, focusing on IVA-VIA compounds and their applications in TE and photodetector technologies. We summarize recent advancements in enhancing these materials’ TE and optical properties and provide an overview of various synthesis techniques for their fabrication. Additionally, we highlight their potential applications as photodetectors in the infrared spectrum. This comprehensive review aims to equip researchers with a deep understanding of the TE and optical properties of 2DMs and their potential applications and to inspire further advancements in this field of research.

In recent years, emerging two-dimensional (2D) materials, such as molybdenum diselenide (MoSe2), have been at the center of attention for many researchers. This is due to their unique and fascinating physicochemical properties that make them attractive in space and defense applications that include shielding harsh irradiation environments. In this study, we examined the effects of gamma (γ) rays at various doses on the structural, chemical, and optical properties of MoSe2 layers. After the samples were exposed to intense gamma radiation (from a 60Co source) with various exposure times to vary the total accumulated dosage (up to 100 kGy), Raman and photoluminescence spectroscopies were used to study and probe radiation-induced changes to the samples. When compared to pristine materials, very few changes in optical properties were typically observed, indicating good robustness with little sensitivity, even at relatively high doses of gamma radiation. The imaging using scanning electron microscopy revealed a number of nano-hillocks that were connected to substrate alterations. X-ray photoelectron spectroscopies revealed that Mo’s binding energies remained the same, but Se’s binding energies blueshifted. We associated this shift with the decrease in Se vacancies that occurred after irradiation as a result of Mo atoms creating adatoms next to Se atoms. When compared to pristine materials, very few changes in optical, chemical, and structural properties were typically observed. These findings highlight the inherent resilience of MoSe2 in hostile radioactive conditions, which spurs additional research into their optical, electrical, and structural characteristics as well as exploration for potential space, energy, and defense applications.

Abstract The capacity to manipulate magnetization in 2D dilute magnetic semiconductors (2D‐DMSs) using light, specifically in magnetically doped transition metal dichalcogenide (TMD) monolayers (M‐doped TX2, where M = V, Fe, and Cr; T = W, Mo; X = S, Se, and Te), may lead to innovative applications in spintronics, spin‐caloritronics, valleytronics, and quantum computation. This Perspective paper explores the mediation of magnetization by light under ambient conditions in 2D‐TMD DMSs and heterostructures. By combining magneto‐LC resonance (MLCR) experiments with density functional theory (DFT) calculations, we show that the magnetization can be enhanced using light in V‐doped TMD monolayers (e.g., V‐WS2, V‐WSe2). This phenomenon is attributed to excess holes in the conduction and valence bands, and carriers trapped in magnetic doping states, mediating the magnetization of the semiconducting layer. In 2D‐TMD heterostructures (VSe2/WS2, VSe2/MoS2), the significance of proximity, charge‐transfer, and confinement effects in amplifying light‐mediated magnetism is demonstrated. We attributed this to photon absorption at the TMD layer that generates electron–hole pairs mediating the magnetization of the heterostructure. These findings will encourage further research in the field of 2D magnetism and establish a novel design of 2D‐TMDs and heterostructures with optically tunable magnetic functionalities, paving the way for next‐generation magneto‐optic nanodevices.

The study of high-entropy materials has attracted enormous interest since they could show new functional properties that are not observed in their related parent phases. Here, we report single crystal growth, structure, thermal transport, and magnetic property studies on a novel high-entropy oxide with the spinel structure (MgMnFeCoNi)Al2O4. We have successfully grown high-quality single crystals of this high-entropy oxide using the optical floating zone growth technique for the first time. The sample was confirmed to be a phase pure high-entropy oxide using x-ray diffraction and energy-dispersive spectroscopy. Through magnetization measurements, we found (MgMnFeCoNi)Al2O4 exhibits a cluster spin glass state, though the parent phases show either antiferromagnetic ordering or spin glass states. Furthermore, we also found that (MgMnFeCoNi)Al2O4 has much greater thermal expansion than its CoAl2O4 parent compound using high resolution neutron Larmor diffraction. We further investigated the structure of this high-entropy material via Raman spectroscopy and extended x-ray absorption fine structure spectroscopy (EXAFS) measurements. From Raman spectroscopy measurements, we observed (MgMnFeCoNi)Al2O4 to display a combination of the active Raman modes in its parent compounds with the modes shifted and significantly broadened. This result, together with the varying bond lengths probed by EXAFS, reveals severe local lattice distortions in this high-entropy phase. Additionally, we found a substantial decrease in thermal conductivity and suppression of the low temperature thermal conductivity peak in (MgMnFeCoNi)Al2O4, consistent with the increased lattice defects and strain. These findings advance the understanding of the dependence of thermal expansion and transport on the lattice distortions in high-entropy materials.

Abstract Endothelial cells (ECs) elongate in the direction of blood flow, are stiffer, and are considered atheroprotective in areas of the vasculature where flow‐induced shear stress is high and unidirectional and are softer, atherogenic, and polygonal in areas experiencing oscillatory multidirectional flow. To understand the precise roles of EC mechanics and morphology in the uptake of therapeutic nanoparticles (NPs) by atherogenic endothelium, human aortic ECs are induced to adopt prescribed shapes and areas imposed by microcontact patterned adhesive islands. NP uptake per cell increases with increasing spreading area and decreases with increasing cell aspect ratio at constant cell spreading area. Biomechanical analysis shows that elongated cells exhibit higher cellular stress and stiffer membranes than cells with low aspect ratios, indicating a strong correlation between morphology, mechanical phenotype, and NP uptake. Further, ECs elongated by high laminar shear endocytosed NPs to a far lesser extent than those that are nonelongated in the chaotic, lower shear areas when cocultured in the same chamber. Results indicate that conditions leading to atherogenesis, such as low, chaotic shear‐induction of EC polygonal morphology may be used to increase the uptake of therapeutic NPs as a preventative measure against atherosclerosis.

Abstract Zinc borates have merits of low voltage polarization and suitable redox potential, but usually suffer from low rate capability and poor cycling life, as an emerging anode candidate for Na+ storage. Here, a new intercalator‐guided synthesis strategy is reported to simultaneously improve rate capability and stabilize cycling life of N, B co‐doped carbon/zinc borates (CBZG). The strategy relies on a uniform dispersion of precursors and simultaneously stimulated combustion activation and solid‐state reactions capable of scalable preparation. The Na+ storage mechanism of CBZG is studied: 1) ex situ XRD and XPS demonstrate two‐step reaction sequence of Na+ storage: Zn6O(OH)(BO3)3+Na++e−↔3ZnO+Zn3B2O6+NaBO2+0.5H2 ①, Zn3B2O6+6Na++6e−↔3Zn+3Na2O+B2O3 ②; reaction ① is irreversible in ether‐based electrolyte while reversible in ester‐based electrolyte. 2) Electrochemical kinetics reveal that ether‐based electrolyte possesses faster Na+ storage than ester‐based electrolyte. The composite demonstrates an excellent capacity of 437.4 mAh g−1 in a half‐cell, together with application potential in full cells (discharge capacity of 440.1 mAh g−1 and stable cycle performance of 2000 cycles at 5 A g−1). These studies will undoubtedly provide an avenue for developing novel synthetic methods of carbon‐based borates and give new insights into the mechanism of Na+ storage in ether‐based electrolyte for the desirable sodium storage.

Abstract Low‐contents/absence of non‐electrochemical activity binders, conductive additives, and current collectors are a concern for improving lithium‐ion batteries' fast charging/discharging performance and developing free‐standing electrodes in the aspects of flexible/wearable electronic devices. Herein, a simple yet powerful fabricating method for the massive production of mono‐dispersed ultra‐long single‐walled carbon nanotubes (SWCNTs) in N‐methyl‐2‐pyrrolidone solution, benefiting from the electrostatic dipole interaction and steric hindrance of dispersant molecules, is reported. These SWCNTs form a highly efficient conductive network to firmly fix LiFePO4 (LFP) particles in the electrode at low contents of 0.5 wt% as conductive additives. The binder‐free LFP/SWCNT cathode delivers a superior rate capacity of 161.5 mAh g−1 at 0.5 C and 130.2 mAh g−1 at 5 C, with a high‐rate capacity retention of 87.4% after 200 cycles at 2 C. The self‐supporting LFP/SWCNT cathode shows excellent mechanical properties, which can withstand at least 7.2 MPa stress and 5% strain, allowing the fabrication of high mass loading electrodes with thicknesses up to 39.1 mg cm−2. Such self‐supporting electrodes display conductivities up to 1197 S m−1 and low charge‐transfer resistance of 40.53 Ω, allowing fast charge delivery and enabling near‐theoretical specific capacities.

Abstract Individual atomic defects in 2D materials impact their macroscopic functionality. Correlating the interplay is challenging, however, intelligent hyperspectral scanning tunneling spectroscopy (STS) mapping provides a feasible solution to this technically difficult and time consuming problem. Here, dense spectroscopic volume is collected autonomously via Gaussian process regression, where convolutional neural networks are used in tandem for spectral identification. Acquired data enable defect segmentation, and a workflow is provided for machine-driven decision making during experimentation with capability for user customization. We provide a means towards autonomous experimentation for the benefit of both enhanced reproducibility and user-accessibility. Hyperspectral investigations on WS2 sulfur vacancy sites are explored, which is combined with local density of states confirmation on the Au{111} herringbone reconstruction. Chalcogen vacancies, pristine WS2, Au face-centered cubic, and Au hexagonal close-packed regions are examined and detected by machine learning methods to demonstrate the potential of artificial intelligence for hyperspectral STS mapping.

Spin-polarized defects in 2D materials are attracting attention for future quantum technology applications, but their controlled fabrication is still challenging. Here, the authors report the creation and characterization of effective spin 1/2 defects via the atomically-precise generation of magnetic carbon radical ions in 2D WS2.

This work evaluates the performance of graphene oxide (GO) - copper ferrite (CuFe2O4) nanohybrid in the removal of Congo Red (CR) dye from aqueous solutions. The adsorbent was prepared via a three-step method. Firstly, GO was produced via a modified Hummers method, using graphite powder as starting material. Following this, GO surface was treated with ionic surfactants, cetyltrimethylammonium bromide (CTAB) and poly(sodium-4-styrenesulfonate) (PSS). Subsequently, the functionalized GO was decorated with magnetic CuFe2O4 nanoparticles via an electrostatic self-assembly process using a solvothermal treatment. The as-synthesized CuFe2O4-GO nanohybrid was characterized by X-Ray Diffraction (XRD) Analysis, Fourier Transform Infrared (FT-IR) Spectroscopy, micro-Raman Spectroscopy, Thermogravimetric Analysis (TGA), Field Emission Scanning Electron Microscopy (FE-SEM), High-Resolution Transition Electron Microscopy (HR-TEM) with Energy Dispersive Spectroscopy (EDS) mapping, as well as, N2 Adsorption/Desorption measurements. We investigated the CR adsorption of the GO-CuFe2O4 nanohybrid at various initial CR concentrations and contact times. Both Langmuir and Freundlich models were employed to describe the adsorption isotherms, while the adsorption kinetics of CR by GO-CuFe2O4 were found to be pseudo-second order. Our results demonstrate that GO-CuFe2O4 is an attractive adsorbent for the efficient removal of CR dye from wastewater.

Non-graphitising carbon materials typically cannot be converted to graphite without the use of metal catalysts. Here, catalyst-free, high-temperature pulsing is shown to convert polyvinylidene chloride and cellulose into highly ordered graphite.

The magnetic proximity effect (MPE) has recently been explored to manipulate interfacial properties of two-dimensional (2D) transition metal dichalcogenide (TMD)/ferromagnet heterostructures for use in spintronics and valleytronics. However, a full understanding of the MPE and its temperature and magnetic field evolution in these systems is lacking. In this study, the MPE has been probed in Pt/WS2/BPIO (biphase iron oxide, Fe3O4 and α-Fe2O3) heterostructures through a comprehensive investigation of their magnetic and transport properties using magnetometry, four-probe resistivity, and anomalous Hall effect (AHE) measurements. Density functional theory (DFT) calculations are performed to complement the experimental findings. We found that the presence of monolayer WS2 flakes reduces the magnetization of BPIO and hence the total magnetization of Pt/WS2/BPIO at T > ~120 K—the Verwey transition temperature of Fe3O4 (TV). However, an enhanced magnetization is achieved at T < TV. In the latter case, a comparative analysis of the transport properties of Pt/WS2/BPIO and Pt/BPIO from AHE measurements reveals ferromagnetic coupling at the WS2/BPIO interface. Our study forms the foundation for understanding MPE-mediated interfacial properties and paves a new pathway for designing 2D TMD/magnet heterostructures for applications in spintronics, opto-spincaloritronics, and valleytronics.

Abstract Background The unique physicochemical properties of multi-walled carbon nanotubes (MWCNT) have led to many industrial applications. Due to their low density and small size, MWCNT are easily aerosolized in the workplace making respiratory exposures likely in workers. The International Agency for Research on Cancer designated the pristine Mitsui-7 MWCNT (MWCNT-7) as a Group 2B carcinogen, but there was insufficient data to classify all other MWCNT. Previously, MWCNT exposed to high temperature (MWCNT-HT) or synthesized with nitrogen (MWCNT-ND) have been found to elicit attenuated toxicity; however, their genotoxic and carcinogenic potential are not known. Our aim was to measure the genotoxicity of MWCNT-7 compared to these two physicochemically-altered MWCNTs in human lung epithelial cells (BEAS-2B & SAEC). Results Dose-dependent partitioning of individual nanotubes in the cell nuclei was observed for each MWCNT material and was greatest for MWCNT-7. Exposure to each MWCNT led to significantly increased mitotic aberrations with multi- and monopolar spindle morphologies and fragmented centrosomes. Quantitative analysis of the spindle pole demonstrated significantly increased centrosome fragmentation from 0.024–2.4 μg/mL of each MWCNT. Significant aneuploidy was measured in a dose-response from each MWCNT-7, HT, and ND; the highest dose of 24 μg/mL produced 67, 61, and 55%, respectively. Chromosome analysis demonstrated significantly increased centromere fragmentation and translocations from each MWCNT at each dose. Following 24 h of exposure to MWCNT-7, ND and/or HT in BEAS-2B a significant arrest in the G1/S phase in the cell cycle occurred, whereas the MWCNT-ND also induced a G2 arrest. Primary SAEC exposed for 24 h to each MWCNT elicited a significantly greater arrest in the G1 and G2 phases. However, SAEC arrested in the G1/S phase after 72 h of exposure. Lastly, a significant increase in clonal growth was observed one month after exposure to 0.024 μg/mL MWCNT-HT & ND. Conclusions Although MWCNT-HT & ND cause a lower incidence of genotoxicity, all three MWCNTs cause the same type of mitotic and chromosomal disruptions. Chromosomal fragmentation and translocations have not been observed with other nanomaterials. Because in vitro genotoxicity is correlated with in vivo genotoxic response, these studies in primary human lung cells may predict the genotoxic potency in exposed human populations.

Sharp atomic interfaces between materials dictate the interface’s electronic properties. The authors use angle-resolved photoemission spectroscopy with a spatial resolution of ~500 nm to investigate the nanoscale electronic band structure and band alignment in a lateral heterostructure composed of WS2 placed on alternating nano-stripes of monolayer and bilayer graphene.

In this work we report the structural and spectroscopic characterization of the bulk MoS _x Se _2-x solid solutions synthesized by chemical vapor transport. The bulk crystals were analyzed by scanning electron microscopy (SEM), x-ray diffraction (XRD), energy dispersive spectroscopy (EDS), atomic force microscopy (AFM), x-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Electron microscopy evaluation of the layered materials shows two distinct types of crystals: flat and easily cleavable hexagonal microcrystals up to 50 μ m in size, and agglomerated irregular crystals of 5–10 μ m in size. XRD shows a consistent increase in interplanar spacing as the Se content is increased in the sample series. Raman spectra of bulk MoS _x Se _2-x obtained with three different excitation energies revealed first order phonon modes associated with pure MoS _2 (x = 2) and MoSe _2 (x = 0) along with a complex behavior of vibrational modes when x had intermediate values. XPS Mo _3d line scans indicate a slight shift towards lower binding energies as the Se/S ratio increases, consistent with the expected energies of MoSe _2 . A simple and direct relationship can be established between the characteristic Raman peaks and the value of x, which can be useful for identifying the compositions of TMD crystals.

Abstract Blood is a complex fluid consisting of cells and plasma. Plasma contains key biomarkers essential for disease diagnosis and therapeutic monitoring. Thus, by separating plasma from the blood, it is possible to analyze these biomarkers. Conventional methods for plasma extraction involve bulky equipment, and miniaturization constitutes a key step to develop portable devices for plasma extraction. Here, we integrated nanomaterial synthesis with microfabrication, and built a microfluidic device. In particular, we designed a double-spiral channel able to perform cross-flow filtration. This channel was constructed by growing aligned carbon nanotubes (CNTs) with average inter-tubular distances of ~80 nm, which resulted in porosity values of ~93%. During blood extraction, these aligned CNTs allow smaller molecules (e.g., proteins) to pass through the channel wall, while larger molecules (e.g., cells) get blocked. Our results show that our device effectively separates plasma from blood, by trapping blood cells. We successfully recovered albumin -the most abundant protein inside plasma- with an efficiency of ~80%. This work constitutes the first report on integrating biocompatible nitrogen-doped CNT (CNxCNT) arrays to extract plasma from human blood, thus widening the bio-applications of CNTs.

Abstract We fabricated ambipolar field-effect transistors (FETs) from multi-layered triclinic ReSe2, mechanically exfoliated onto a SiO2 layer grown on p-doped Si. In contrast to previous reports on thin layers (~2 to 3 layers), we extract field-effect carrier mobilities in excess of 102 cm2/Vs at room temperature in crystals with nearly ~10 atomic layers. These thicker FETs also show nearly zero threshold gate voltage for conduction and high ON to OFF current ratios when compared to the FETs built from thinner layers. We also demonstrate that it is possible to utilize this ambipolarity to fabricate logical elements or digital synthesizers. For instance, we demonstrate that one can produce simple, gate-voltage tunable phase modulators with the ability to shift the phase of the input signal by either 90° or nearly 180°. Given that it is possible to engineer these same elements with improved architectures, for example on h-BN in order to decrease the threshold gate voltage and increase the carrier mobilities, it is possible to improve their characteristics in order to engineer ultra-thin layered logic elements based on ReSe2.

Carbon nanotube (CNT) sponge exhibits unique porous and hierarchical structure that are beneficial to the design of ultralight and tough composites. In this study, CNT sponges (undoped and boron doped) reinforced polydimethylsiloxane (PDMS) composites were fabricated. Mechanical properties of the composite, including compressive modulus, rate-dependent modulus, stress relaxation behaviors, dynamic viscoelastic properties, and their dependency on temperature, were systematically investigated. A micromechanical model, Mori-Tanaka model, was validated to describe the mechanical behaviors of CNT sponge reinforced composites. By coupling with boron-doped CNT sponge, PDMS composites showed remarkable improvement of mechanical properties, including compressive modulus (70%), viscous modulus (243%) and damping capacity (50%). Such reinforcement effects can be controlled by the morphology of CNT sponges, as the boron-doped and undoped nanocomposites showed distinct viscoelastic behaviors. The results proved that CNT sponge reinforcement is a promising strategy to develop engineering composites with both outstanding mechanical stiffness and controllable viscoelastic performances. Keywords: Carbon nanotube sponges, Nanocomposite, Viscoelastic, Damping, Micromechanics modeling

Abstract Influenza A viruses (IAVs) continue to threaten animal and human health globally. Bats are asymptomatic reservoirs for many zoonotic viruses. Recent reports of two novel IAVs in fruit bats and serological evidence of avian influenza virus (AIV) H9 infection in frugivorous bats raise questions about the role of bats in IAV epidemiology. IAVs bind to sialic acid (SA) receptors on host cells, and it is widely believed that hosts expressing both SA α2,3-Gal and SA α2,6-Gal receptors could facilitate genetic reassortment of avian and human IAVs. We found abundant co-expression of both avian (SA α2,3-Gal) and human (SA α2,6-Gal) type SA receptors in little brown bats (LBBs) that were compatible with avian and human IAV binding. This first ever study of IAV receptors in a bat species suggest that LBBs, a widely-distributed bat species in North America, could potentially be co-infected with avian and human IAVs, facilitating the emergence of zoonotic strains.

Double-resonance Raman scattering is a sensitive spectroscopic probe of the interplay between electrons and phonons in a crystal. Here, the authors unveil the signature of double-resonance intervalley scattering by acoustic phonons in two-dimensional MoS2, underpinning the physics of valley depolarization.

Two-dimensional (2D) materials have shown promise in various optical and electrical applications. Among these materials, semiconducting transition metal dichalcogenides (TMDs) have been heavily studied recently for their photodetection and thermoelectric properties. The recent progress in fabrication, defect engineering, doping, and heterostructure design has shown vast improvements in response time and sensitivity, which can be applied to both contact-based (thermocouple), and non-contact (photodetector) thermal sensing applications. These improvements have allowed the possibility of cost-effective and tunable thermal sensors for novel applications, such as broadband photodetectors, ultrafast detectors, and high thermoelectric figures of merit. In this review, we summarize the properties arisen in works that focus on the respective qualities of TMD-based photodetectors and thermocouples, with a focus on their optical, electrical, and thermoelectric capabilities for using them in sensing and detection.

We demonstrated that the ball-milled slag-SiC mixture is an effective catalyst to grow pyrrolic nitrogen-doped multiwall carbon nanotubes (N-MWCNTs) by aerosol assisted chemical vapor deposition (AACVD) method. N-MWCNTs synthesized at 800 °C, 850 °C and 900 °C were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, x-ray powder diffraction (XRD), and x-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). TEM characterizations revealed the presence of a bamboo-like structure, a typical feature of nitrogen-doped carbon nanotubes. The presence of nitrogen was confirmed by the N1s XPS spectrum. Furthermore, a deconvolution of the N1s spectra revealed the presence of N-pyrrolic defects. This nitrogen functionality is investigated concerning the presence of silicon carbide material. Giant nanotubes with large diameters were obtained when SiC was added to the slag to be used as a substrate for N-MWCNTs synthesis. From Raman spectroscopy, the appearance of the D-band was observed, indicating the presence of topological defects that were also observed by TEM. XRD and TEM characterizations demonstrated the presence of Fe _3 C and α -Fe nanoparticles. The N-MWCNTs fabricated here could be used into (electro)catalytic applications or for reinforcing ceramic nanomaterial or polymers.