Carbon Nanomaterials Research Articles

Development of carbon composite coatings for fire retardancy and electromagnetic interference shielding

This study has effectively showcased the feasibility of employing a carbon composite coatings, comprised of various carbon nanomaterials including carbon nanodots, carbon nanotubes, and graphene nanosheets integrated within a matrix of sodium metasilicate + gypsum, for applications in both flame retardancy and electromagnetic interference (EMI) shielding. The resulting carbon composite coatings, when applied to wooden substrates, demonstrate remarkable fireproof performance, as validated through fire injections at temperatures as high as 1050 °C. This underscores the pivotal role plays by the design of carbon composites in suppressing flame propagation and charring, leading to reduced carbonization areas. Thermogravimetric analysis further reveals that the carbon composite coating generates substantial char residue at 800 °C, signifying enhanced thermal insulating properties derived from the robust composite carbon architecture. Furthermore, the carbon composite coatings show a significant decrease in electromagnetic fields (electric field around 50 % and magnetic field around 44 %), indicating their efficient EMI shielding properties. This improved EMI shielding performance may be due to the deliberate insertion of CNs into the composite materials, which fine-tunes resistance and dielectric loss while allowing effective electromagnetic absorption by the carbon composites. The breakthroughs made in flame retardancy and EMI shielding highlight carbon composites as superior strengthens to flame-retardant and EMI-absorbing building coatings.

Photochromic Carbon Nanomaterials: An Emerging Class of Light-Driven Hybrid Functional Materials.

Photochromic molecules have remarkable potential in memory and optical devices, as well as in driving and manipulating molecular motors or actuators and many other systems using light. When photochromic molecules are introduced into carbon nanomaterials (CNMs), the resulting hybrids provide unique advantages and create new functions that can be employed in specific applications and devices. This review highlights the recent developments in diverse photochromic CNMs. Photochromic molecules and CNMs are also introduced. The fundamentals of different photochromic CNMs are discussed, including design principles and the types of interactions between CNMs and photochromic molecules via covalent interactions and non-covalent bonding such as π-π stacking, amphiphilic, electrostatic, and hydrogen bonding. Then the properties of photochromic CNMs, e.g., in photopatterning, fluorescence modulation, actuation, and photoinduced surface-relief gratings, and their applications in energy storage (solar thermal fuels, photothermal batteries, and supercapacitors), nanoelectronics (transistors, molecular junctions, photo-switchable conductance, and photoinduced electron transfer), sensors, and bioimaging are highlighted. Finally, an outlook on the challenges and opportunities in the future of photochromic CNMs is presented. This review discusses a vibrant interdisciplinary research field and is expected to stimulate further developments in nanoscience, advanced nanotechnology, intelligently responsive materials, and devices.

Nanosheets adsorption and antiviral activity of Favipiravir drug against envelope proteins of yellow fever virus: DFT and molecular docking simulation study

Our previous research investigated the delivery of Favipiravir (FAV) drug through the encapsulation of FAV into 1D nanomaterials (NMs), AlN, BN, and carbon nanotubes, now we evaluated the possibility of using 2D NMs carbon nanosheets (GPNS), boron nitride nanosheets (BNNS), and aluminum nitride nanosheets (AlNNS) as drug delivery systems. The adsorption of FAV drug in its two tautomeric forms over the surfaces of these NSs is conducted. The adsorption energies are in the range of − 0.681 to − 2.469 eV. FAV binds to BNNS and GPNS through stacking interactions, while it chemisorbs to AlNNS. NCI and QTAIM analyses confirmed the dominance of vdW interactions. The recovery times over NSs were shorter than those inside NTs, and they indicated that NSs are better for drug release while NTs bind better and have larger adsorption energies. MD simulations revealed that FAV showed a good level of resistance to yellow fever virus (YFV) infections.

Selective and Sensitive Detection of Cu+ in Living Cells Based on Chelator Modified Carbon Dots

AbstractCuprous ions (Cu+) are essential for various biological activities. However, it is still a great challenge to detect Cu+ efficiently in cells in situ. As emerging 0‐D carbon photoluminescence nanomaterials, carbon dots (CDs) exhibit non‐toxicity and ultra stability, which shows great advantages in biosensing and bioimaging. In this work, CDs are prepared by a one‐step microwave‐assisted hydrothermal method. To enhance the selectivity and efficiency of the CDs‐based sensor, the NS4‐CDs are synthesized by surface modification of CDs using Cu+ chelating molecules. The NS4‐CDs, that carry specific detection molecules, exhibit remarkable selectivity and high sensitivity with an extraordinarily low detection limit (26 nmol L−1). It is noteworthy that the detection response is extremely fast, which only takes 20 s. The PL response mechanism of NS4‐CDs is also thoroughly investigated. In addition, the NS4‐CDs possess great biocompatibility and non‐cytotoxicity, which is vital for advanced cellular imaging applications. Finally, the NS4‐CDs are successfully applied to Cu+ detection in cells in situ. This work paves a new path for the design and efficient construction of CDs‐based biosensors for ion detection in cells, which expands the application area of carbon nanomaterials.

N, N-Dimethylformamide assisted matrix to realize carbon nanomaterials from fluorescence to afterglow

Carbon nanomaterials (CNMs) with afterglow property have received extensive attention and are of great help to luminescent functional materials. However, it is still challenging to realize the afterglow properties of CNMs, such as the effective realization of afterglow and stable afterglow properties. In this work, we processed boric acid (BA) with N, N-dimethylformamide (DMF) to form a matrix by microwave, modified the CNMs produced by benzene-1,3.5-tricarboxylic acid (BTA) and tetraethylenepentamlne (TEPA) in two steps, and successfully prepared CNMs with yellow or green afterglow characteristic. The rotational freedom of the first-step material is limited by the formation of a BA-MDF matrix, which effectively suppresses the nonradiative transition and triple exciton deactivation, and the presence of a rigid structure limits the spin-orbit coupling (SOC) and promotes the energy levels to jump to the triple state to realize the afterglow properties. In addition, we used CNMs with afterglow as two-dimensional color block arrangement materials to realize anti-counterfeiting and information encryption, which has certain application value for related fields.

Highly porous layered carbon nanocomposites from the self-assembly of a poly(amic acid) for efficient oxygen reduction reaction catalysis

Porous layered carbon nanomaterials play important role in the efficient loading of electroactive substances for high performance energy conversion techniques. Herein, an intramolecular cyclization induced self-assembly (ICISA) strategy is proposed to prepare three-dimensional highly porous layered carbon nanostructures (LCs) for efficient loading of various transition metal nanoparticles for oxygen reduction reaction (ORR) catalysis. The amphiphilic alternating copolymer poly(amic acid) (PAA) is synthesized by the stepwise polymerization of hydrazine hydrate and pyromellitic dianhydride. Upon heating above 160 °C, the intramolecular cyclization reaction occurs, leading to the formation of rigid, crystalline and non-soluble polyimide segments in the backbone, which induces the self-assembly of the polymer to form dumbbell-shaped assemblies with a high solid content of 15%. After pyrolysis in a nitrogen atmosphere, LCs are obtained. Cobalt (Co), iron (Fe) and FeCo nanoparticles can be efficiently loaded, noted as Co@LCs, Fe@LCs and FeCo@LCs, respectively. The ORR catalytic performance of the catalysts is evaluated to give half wave potentials of 0.791, 0.787 and 0.812 V, and limit current densities of 4.92, 4.73 and 4.71 mA cm−2 for Co@LCs, Fe@LCs and FeCo@LCs, respectively. Overall, we propose an ICISA strategy to facilely prepare three-dimensional carbon nanomaterials with highly porous layered structure for efficient ORR catalysis.

Preparation of μ-HMX/C-Based Composite Energy Composite Microspheres by Microdroplet Technology.

Taking μ-HMX particles as the main research subject, a set of microdroplet sphericalization coating technology platforms was designed and constructed to realize the preparation of composite microspheres by sphericalization coating of μ-HMX. The suspension stability of μ-HMX particles and the mechanism of droplet formation were investigated, and the application effect of nanocarbon materials was also analyzed. The results showed that the prepared sample microspheres all showed a better spherical morphology, as well as good dispersibility; the samples with micron-sized particles for spherical coating had a lower thermal decomposition temperature, a higher energy release efficiency, lower mechanical sensibility, and better combustion performance; the incorporation of CNFs changed the combustion mode of the system, which resulted in the microsphere system of μ-HMX having a good safety performance. The stability and feasibility of uniform spheronization when the dispersed phase is a low-concentration particle suspension system in the spheronization encapsulation process by microdroplet technology were verified.

Performance of carbon nanomaterials incorporated with concrete exposed to high temperature

Abstract In recent decades, there have been initiatives to incorporate carbon nanomaterials (CNMs) into cement composites, particularly graphene oxide (GO), carbon nanotubes, graphite (GP), and mild carbon (MC). Nevertheless, little is known about how these CNMs interact with the cement matrix itself. In this research, the impact of CNM incorporation at high temperatures (250, 500, 750, and 1,000°C) on cement’s mechanical characteristics and microstructure was investigated. Nine mixes were created with the CNM content (0.1 and 0.3%) being taken into consideration. The microstructure of the CNM composites was further investigated using X-ray diffractometry, thermogravimetry, derivative thermogravimetry, digital microscopy, and micro-computed tomography (micro-CT). Based on research observations, the study demonstrated that the mechanical properties of most specimens could be enhanced through the introduction of CNMs. The recommended proportions of GP-0.1, GO-0.1, and MC-0.1, in accordance with the weight of the binder, and the impact of the CNMs on the elastic modulus were also assessed. As a consequence, the CNM’s porous structure and apparent crack pattern were identified using microstructure analysis.

Combined toxic effects of fluxapyroxad and multi-walled carbon nanotubes in Xenopus laevis larvae

Carbon nanomaterials rarely exist in isolation in the natural environment, and their combined effects cannot be ignored. Multi-walled carbon nanotubes (MWCNTs) have shown tremendous potential applications in diverse fields, including pollution remediation, biomedicine, energy, and smart agriculture. However, the combined toxicities of MWCNTs and pesticides on non-target organisms, particularly amphibians, are often overlooked. Fluxapyroxad (FLX), a significant succinate dehydrogenase inhibitor fungicide, has been extensively utilized for the protection of food and cash crops and control of fungi. This raises the possibility of coexistence of MWCNTs and FLX. The objective of this study was to explore the individual and combined toxic effects of FLX and MWCNTs on the early life stages of Xenopus laevis. Embryos were exposed to varying concentrations of FLX (0, 5, and 50 μg/L) either alone or in combination with MWCNTs (100 μg/L) for a duration of 17 days. The findings indicated that co-exposure to FLX and MWCNTs worsened the inhibition of growth, liver damage, and dysregulation of enzymatic activity in tadpoles. Liver transcriptomic analysis further revealed that the presence of MWCNTs exacerbated the disturbances in glucose and lipid metabolism caused by FLX. Additionally, the combined exposure groups exhibited amplified alterations in the composition and function of the gut microflora. Our study suggests that it is imperative to pay greater attention to the agricultural applications, management and ecological risks of MWCNTs in the future, considering MWCNTs may significantly enhance the toxicity of FLX.

Innovative Nanotechnology in Drug Delivery Systems for Advanced Treatment of Posterior Segment Ocular Diseases.

Funduscopic diseases, including diabetic retinopathy (DR) and age-related macular degeneration (AMD), significantly impact global visual health, leading to impaired vision and irreversible blindness. Delivering drugs to the posterior segment of the eye remains a challenge due to the presence of multiple physiological and anatomical barriers. Conventional drug delivery methods often prove ineffective and may cause side effects. Nanomaterials, characterized by their small size, large surface area, tunable properties, and biocompatibility, enhance the permeability, stability, and targeting of drugs. Ocular nanomaterials encompass a wide range, including lipid nanomaterials, polymer nanomaterials, metal nanomaterials, carbon nanomaterials, quantum dot nanomaterials, and so on. These innovative materials, often combined with hydrogels and exosomes, are engineered to address multiple mechanisms, including macrophage polarization, reactive oxygen species (ROS) scavenging, and anti-vascular endothelial growth factor (VEGF). Compared to conventional modalities, nanomedicines achieve regulated and sustained delivery, reduced administration frequency, prolonged drug action, and minimized side effects. This study delves into the obstacles encountered in drug delivery to the posterior segment and highlights the progress facilitated by nanomedicine. Prospectively, these findings pave the way for next-generation ocular drug delivery systems and deeper clinical research, aiming to refine treatments, alleviate the burden on patients, and ultimately improve visual health globally.

Iron Oxide-Doped Carbon Nanoparticles Stabilised with Functionally Modified Hyperbranched Polyglycerol for Cd2+ Sensing and Photodynamic Antibacterial Therapeutic Applications.

Nanoscale materials are being developed from individual particles to multi-component assemblies, with carbon nanomaterials being particularly useful in bioimaging, sensing, and optoelectronics due to their unique optical properties, enhanced by surface passivation and chemical doping. Noble metals are commonly used in conjunction with carbon-based nanomaterials for the synthesis of nanohybrids. Carbon-based materials can function as photosensitizers and effective carriers in photodynamic therapy, enabling the use of combined treatment approaches. The hydrophobicity and agglomeration tendency of carbon nanoparticles pose a drawback. This study is an attempt to overcome these limitations, which involved the synthesis of iron oxide-doped carbon nanoparticles through the carbonisation of citric acid and hexamethylene tetramine, followed by doping them with iron oxide. The as synthesized iron oxide-doped carbon nanoparticles were stabilised with fluorescently modified hyperbranched polyglycerol. The efficacy of these nanoparticles in photodynamic antibacterial therapy and Cd (II) ion sensing was investigated. The selectivity of stabilised nanoparticles against Cd2+ ion is presented in the current study. The current study also compares the antibacterial efficacy of undoped, iron oxide-doped and stabilised nanoparticle systems. The possible toxic effects of the synthesised nanosystems were investigated in order to assess their suitability for biomedical applications and establish their safety profile.

Nano-delivery platforms for bacterial gene transformation: suitability and challenges.

Nano-scale particles (NPs) have gained increased interest as non-viral vectors for nucleic acid delivery due to their ability to penetrate through unabraded cell membranes. The previous studies performed have evaluated the nanomaterials for their microbial transformation proficiency but have not compared the relative efficacy. The present study aims to identify the most proficient nano-delivery vehicle among the chemically synthesized/functionalized non-metal oxide, metal/metal oxide, and carbon-based (carbon nanotube (CNT), graphene oxide (GO)) nanomaterial(s) (NMs) for the transformation of two gram-negative bacteria, i.e., Escherichia coli and Agrobacterium tumefaciens. The microscopy and spectroscopy studies helped to identify the interaction, adhesion patterns, transformation efficiencies, better delivery, and expression of the target gfp gene by use of NMs. Loading of pgfp on all NMs imparted protection to DNAse I attack except ZnO NPs with maximum by chitosan, layered double hydroxide (LDH), and GO NM-plasmid DNA conjugates. The CNTs and GO significantly enhanced the extra- and intra-cellular protein content, respectively, in both bacteria. However, GO and CNT significantly decreased the cell viability in a time-dependent manner while AuNPs exhibited negligible cell toxicity. Therefore, this study identified the comparative efficiency of metal/metal oxide, non-metal oxide, and carbon nanomaterials with AuNPs as the most biosafe while LDH and chitosan NPs being the most proficient alternative tools for the genetic transformation of gram-negative bacteria by simple incubation method.

On-Surface Covalent Synthesis of Carbon Nanomaterials by Harnessing Carbon gem-Polyhalides.

The design of innovative carbon-based nanostructures stands at the forefront of both chemistry and materials science. In this context, π-conjugated compounds are of great interest due to their impact in a variety of fields, including optoelectronics, spintronics, energy storage, sensing and catalysis. Despite extensive research efforts, substantial knowledge gaps persist in the synthesis and characterization of new π-conjugated compounds with potential implications for science and technology. On-surface synthesis has emerged as a powerful discipline to overcome limitations associated with conventional solution chemistry methods, offering advanced tools to characterize the resulting nanomaterials. This review specifically highlights recent achievements in the utilization of molecular precursors incorporating carbon geminal (gem)-polyhalides as functional groups to guide the formation of π-conjugated 0D species, as well as 1D, quasi-1D π-conjugated polymers, and 2D nanoarchitectures. By delving into reaction pathways, novel structural designs, and the electronic, magnetic, and topological features of the resulting products, the review provides fundamental insights for a new generation of π-conjugated materials.

A review on cementitious composite incorporating carbon nanomaterials: The self-sensing functionality as an implication for geological CO2 storage monitoring

Ensuring the long-term security and safety of geological CO2 storage relies on the durability of wellbores and cement. Addition of carbon-based nanomaterials (CNMs) have enhanced traditional cement, improving cement properties, and preventing gas migration. Despite these advancements, their potential for self-monitoring in GCS remains understudied. Self-sensing cementitious composites (SSC) are gaining attention for their ability to detect risks and damages, like cracks and corrosion, by monitoring environmental changes. This review first scrutinizes the self-sensing mechanism of SSC, including piezoresistivity, electrical resistivity and conductivity. The commonly used CNMs in SSC, such as carbon nanotubes (CNTs), carbon nanofibers (CNFs), carbon black (CB), and graphene nanoplatelets (GNPs), along with the hybrid nanocomposites, detailing recent advancements. Based on their effects, such as enabling the measurement of electrical response to strain, real-time monitoring of structural integrity, and improvement in cement performance, the implications are made for GCS cases, for instance, structural health monitoring and detecting leakage. Technical challenges, such as balancing electrical properties and mechanical strength, scalability, and environmental sensitivity, are addressed, along with insights on employing machine learning algorithms to optimize SSC usage. Finally, future directions for integrating SSC into GCS initiatives are proposed.

Ultra‐high Capacity and Stable Dual‐ion Batteries with Fast Kinetics Enabled by HOF Supermolecules Derived 3D Nitrogen‐Oxygen Co‐doped Nanocarbon Anodes

AbstractThe low capacity, poor cycling life, and rapid self‐discharge hinder the development of carbonaceous dual‐ion batteries (DIBs). Conventional preparations of element doping amorphous carbons are cumbersome, complex, and difficult to control the doping element, content, and size. Here, a nitrogen‐oxygen co‐doped amorphous carbon nanomaterial (NDC) with unique 3D vortex‐layered amorphous structure and high doping content is ingeniously prepared via self‐assembly of hydrogen‐bonded organic framework precursors followed by one‐step pyrolysis, and then used for anodes of DIBs. By pairing with a commercial Nylon separator, a self‐supporting independent graphite cathode, and a high‐concentration electrolyte, the NDC‐based DIBs display an ultra‐high specific discharge capacity of up to 519 mAh g−1 at 1 C, low self‐discharge rate of 0.85% h−1, capacity retention of 98.8% after 1500 cycles, and fast kinetic dynamics. This study offers a novel approach to enable carbonaceous nanomaterials for energy‐dense and long‐cycling DIBs.

Superhydrophobic biochars as catalysts for efficient hydrogen transfer in N-heterocycles and nitrobenzene reactions

The heteroatom-doped carbon nanomaterials can be the active catalysts in hydrogen transfer reactions, however, carbon-catalyzed hydrogen transfer processes in the absence of additives and cocatalysts have been rarely described. Herein, functional biochar catalysts (FBCs) were successfully fabricated from wheat straw by a simple scalable two-step strategy via reconstructing the catalytic active sites in carbon precursors and subsequently controlled carbonization. The characterization of FBCs was discussed with regard to morphologic structures, chemical constitutions and performance, revealing that the high hydrophobicity is beneficial for obtaining high activity. Wherein the optimized FBC-850 catalyst exhibited high activity and durability toward the reaction of N-heterocycles and nitrobenzene in the aqueous systems due to the synergistic effects that were attributed to the external superhydrophobicity, internal capillary repulsion and hydrogen transfer property, eliminating the need for additional co-catalysts or additives. In the model reaction, the yields of quinoline and aniline were respectively achieved at 92% and 90%. Furthermore, the encapsulated quinone units as the active sites in FBC-850 formed the bipyramidal structure, enabling the hydrogen transfer process through a cyclical hydrogen exchange, which was proved from kinetic studies combined with spectral characterization and theoretical calculation. In addition, a possible reaction mechanism was proposed based on the observation of key intermediates and DFT calculations, also providing a rationale for the existing active site structures.

Schwarzites and Triply Periodic Minimal Surfaces: From Pure Topology Mathematics to Macroscale Applications.

Schwarzites are porous (spongy-like) carbon allotropes with negative Gaussian curvatures. They are proposed by Mackay and Terrones inspired by the works of the German mathematician Hermann Schwarz on Triply-Periodic Minimal Surfaces (TPMS). This review presents and discusses the history of schwarzites and their place among curved carbon nanomaterials. The main works on schwarzites are summarized and are available in the literature. Their unique structural, electronic, thermal, and mechanical properties are discussed. Although the synthesis of carbon-based schwarzites remains elusive, recent advances in the synthesis of zeolite-templates nanomaterials have brought them closer to reality. Atomic-based models of schwarzites are translated into macroscale ones that are 3D-printed. These 3D-printed models are exploited in many real-world applications, including water remediation and biomedical ones.

Carbon nanomaterials: Pioneering innovations in bioimaging and biosensing technologies

Carbon-based nanomaterials, including carbon nanotubes, graphene, carbon dots, carbon nano onions, and carbon nano horns, exhibit exceptional properties such as high electrical and thermal conductivity, mechanical strength, and biocompatibility. These characteristics make them attractive for various biomedical applications, particularly in bioimaging and biosensing. In bioimaging, carbon-based nanomaterials offer several advantages. Their unique properties enable precise imaging of biological events in cells, tissues, and organs, with minimal interference in living processes. By leveraging these properties, researchers can achieve high-resolution imaging for accurate diagnosis and therapy. Similarly, carbon-based nanomaterials are crucial in biosensing applications. They provide a platform for developing highly sensitive biosensors due to their distinctive electrical properties and surface characteristics. Functionalizing these nanomaterials with specific biomolecules or receptors allows for the detection and extraction of target molecules with exceptional precision and sensitivity, inspired by principles found in living systems. A review article focusing on the applications of carbon-based nanomaterials in bioimaging and biosensing would provide insights into their potential in advancing biotechnology. This article discusses a variety of carbon-based nanomaterials, including carbon nanotubes, graphene, carbon dots, carbon nano onions, and carbon nano horns, emphasizing their unique properties and applications in bioimaging and sensing. The review emphasizes the importance of detection accuracy and sensitivity in biomedical applications and investigates how carbon-based nanomaterials help to advance biotechnology. This exploration will allow researchers to explore and create novel diagnostic and therapeutic methods.

Molecular-Imprinting Assisted Polydopamine-Aptasensor On Carbon and Gold Nanomaterials Construct for The Haemophilia B Biomarker Detection

The study presents a comprehensive approach for enhancing the performance of a spiral micro-interdigitated electrode (spiral-μIDE) sensor for the detection of FIX protein. Electropolymerization using dopamine resulted in a molecular-imprinted polymer (polyDOP-μIDE-MIP) layer, which encapsulated the aptamer-FIX complex and was later leached to create cavities. Cyclic and linear-sweep voltammetry techniques were utilized for the MIP development and rebinding assessment. Linear sweep voltammetry demonstrated a linear relationship between FIX concentration and peak current reduction, with a limit of detection (LOD) of 0.250 picomolar. The sensor's sensitivity was determined as 2.613E-10 A.fM-1.μm-2. This work highlights the importance of nanomaterials integration, and electropolymerization in improving sensor performance. The integration of carbon and gold nanomaterials and the use of molecular imprinting contribute to the sensor's enhanced sensitivity and selective detection of FIX protein.

Nanocellulose: The Ultimate Green Aqueous Dispersant for Nanomaterials.

Nanocellulose, a nanoscale derivative from renewable biomass sources, possesses remarkable colloidal properties in water, mechanical strength, and biocompatibility. It emerges as a promising bio-based dispersing agent for various nanomaterials in water. This mini-review explores the interaction between cellulose nanomaterials (nanocrystals or nanofibers) and water, elucidating how this may enable their potential as an eco-friendly dispersing agent. We explore the potential of nanocellulose derived from top-down processes, nanocrystals, and nanofibers for dispersing carbon nanomaterials, semiconducting oxide nanoparticles, and other nanomaterials in water. We also highlight its advantages over traditional methods by not only effectively dispersing those nanomaterials but also potentially eliminating the need for further chemical treatments or supporting stabilizers. This not only preserves the exceptional properties of nanomaterials in aqueous dispersion, but may even lead to the emergence of novel hybrid functionalities. Overall, this mini-review underscores the remarkable versatility of nanocellulose as a green dispersing agent for a variety of nanomaterials, inspiring further research to expand its potential to other nanomaterials and applications.