Carbon Nanomaterials Research Articles

Carbon-based nanocomposites for sensing applications-a review

Abstract Carbon-based nanomaterials exhibit unique morphological and physical properties. When used as fillers in various matrices such as polymers, they can provide enhanced electrical, thermal and mechanical characteristics. The emerging field of sensing technologies has witnessed remarkable advancements, resulting from the integration of carbon-based nanocomposites. This paper presents a comprehensive review of the latest developments in key carbon-based nanocomposite sensors. First, the unique properties of carbon nanomaterials are reviewed covering the full dimensional spectrum, followed by main synthesis routes addressing critical aspects such as morphology, surface functionalization, and doping strategies. Later, the synergistic effects arising from the combination of carbon nanomaterials with other components, such as polymers, are explored in detail, emphasizing the role of percolation levels in the overall sensing performance. The different sensing applications presented in this review cover a broad range, including strain, temperature, gas and biosensing. The mechanisms and principles governing the sensing capabilities of carbon-based nanocomposites are provided, shedding light on the interactions between analytes and nanocomposite surfaces. A critical analysis of current challenges and prospects is also presented, outlining potential avenues for further research and innovation. Finally, this review aims to serve as a valuable resource for researchers interested in carbon-based nanocomposites and their evolving role in advancing sensing technologies.

Molecular dynamics study on the enhancement of high‐temperature friction and mechanical properties of perfluoroelastomers by carbon nanomaterials

AbstractThe mechanical and frictional properties of pure perfluoroelastomer, graphene (GN)/perfluoroelastomer, and carbon nanotube (CNT)/perfluoroelastomer composite systems were investigated using molecular dynamics simulations. The influence of carbon nanomaterials on the glass transition temperature, mechanical properties, and frictional behavior of perfluoroelastomers at various temperatures was evaluated. The simulation results demonstrated that the addition of GN and CNTs increased the glass transition temperature of perfluoroelastomers to varying extents. CNTs enhanced the mechanical properties of perfluoroelastomers more effectively than GN, whereas GN provided superior improvement in frictional properties compared to CNTs. Analysis of stress–strain distribution, atomic motion trajectory, interaction energy, mass density, and temperature distribution, bond orientation parameters, radial distribution function (RDF), mean square displacement (MSD), and diffusion coefficients revealed the mechanisms and differences by which GN and CNTs enhance the mechanical and frictional properties of perfluoroelastomers.Highlights Carbon nanomaterials enhance perfluoroelastomer's high‐temperature performance. CNTs provide higher mechanical strength but lower wear resistance. GN nanosheets outperform CNTs in reducing friction and wear. Molecular dynamics simulations reveal distinct enhancement mechanisms.

Preparation, Purification, and Hydrophilization of Magnetic-Carbon Nanofibers

This study aims to synthesize, purify, and modify magnetic carbon nanofibers (Mag-CNF) into hydrophilic carbon material. The synthesis method was carried out by chemical vapor deposition (CVD) using the catalyst from Incolloy at 800°C with argon, nitrogen, hydrogen, and acetylene gases. The purification of Mag-CNF was then conducted by dissolving Mag-CNF with toluene and ethanol, followed by vacuum annealing. The hydrophilization of Mag-CNF was further performed by adding amine groups via reacting Mag-CNF with ethylene diamine, NaNO2, and H2SO4. The successfully prepared Mag-CNF has characteristics of tubular tube bundles consisting of carbon nanofibers with an average diameter of 100-120 nm. The X-ray diffraction (XRD) profile shows the characteristics of carbon, iron, iron oxide, and iron carbide. The Raman spectra show the existence of D, G, and G' bands corresponding to the characteristics of carbon nanomaterials. The magnetic property characterization using a vibration sample magnetometer (VSM) shows the synthesized product as ferrimagnetic materials. The modification results show the addition of hydrophilic groups to Mag-CNF, such as O–H and N–H groups, as analyzed in Fourier Transform Infrared (FTIR) spectra. The successful hydrophilization was also visually confirmed using a dispersion test in water, showing that Mag-CNF has better dispersion after surface modification.

First-principles study on a new 2D carbon allotrope with an intrinsic wide bandgap: A comparison with α-graphyne

Nanocarbon materials with intrinsic electronic bandgaps are highly desirable for next-generation carbon-based nanoelectronics. Herein, a new two-dimensional (2D) carbon allotrope with structural similarities to α-graphyne has been proposed theoretically, which exhibits intrinsic semiconducting behavior with a wide direct bandgap significantly larger than that reported in other 2D carbon allotropes. Based on first-principles calculations, the structural and electronic properties of the new 2D carbon allotrope, as well as its lattice stability, have been systematically investigated by adopting a comparative study with α-graphyne. Moreover, the effects of vertical stacking and in-plane biaxial strain on the new 2D carbon allotrope have also been clarified in this work, providing robust approaches for the effective modulation of electronic properties in the new 2D carbon allotrope. Thus, the intrinsic wide bandgap, along with effective modulations, suggests great advantages and potentials of the new 2D carbon allotrope in carbon-based electronic devices and light-emitting applications.

The Preparation of Biomass-Derived Carbon Dots and Its Application Prospect in the Field of Vascular Stent Coating

Biomass material serves as one of the most advantageous carbon sources for the synthesis of carbon dots (CDs) due to its abundant availability, cost-effectiveness, and environmental sustainability. Biomass-derived carbon dots (B-CDs), which are new zero-dimensional carbon nanomaterials, have presented broad application prospects in the medical field and have become a research focus. In recent years, the death rate caused by vascular diseases has been high, and interventional therapy is one of the important means to treat vascular stenosis. As a material with excellent biocompatibility and fluorescence properties, B-CDs have shown great potential in the field of vascular stents, and their unique properties provide new ideas and possibilities for improving the biocompatibility of vascular stents and realizing real-time tracer diagnosis. This paper reviews the preparation methods, modification techniques, and application prospects of B-CDs in the coating of vascular stents. It discusses current challenges and potential solutions while forecasting future development directions, thereby providing innovative insights and pathways for the research and development of a new generation of vascular stents.

CuS-NiTe2 embedded phosphorus-doped graphene oxide catalyst for evaluating hydrogen evolution reaction.

The hydrogen evolution reaction (HER), a crucial half-reaction in the water-splitting process, is hindered by slow kinetics, necessitating efficient electrocatalysts to lower overpotential and enhance energy conversion efficiency. Transition-metal electrode materials, renowned for their robustness and effectiveness, have risen to prominence as primary contenders in the field of energy conversion and storage research. In this investigation, we delve into the capabilities of transition metals when employed as catalysts for the HER. Furthermore, we turn our attention to carbon nanomaterials like graphene, which have exhibited tremendous potential as top-performing electrocatalysts. Nevertheless, advancements are indispensable to expand their utility and versatility. One such enhancement involves the integration of phosphorus-doped graphene. Our research focuses on the synthesis of CuS-NiTe2/PrGO, a nanocomposite with a crystalline structure, through a straightforward method. This nanocomposite exhibits enhanced catalytic activity for the HER, boasting a Tafel slope of 57 mV dec-1 in an acidic environment. Consequently, our findings present a straightforward and efficient approach to developing high-performance electrocatalysts for HER.

Nanocarbon Materials: Synthesis of Newly Discovered Carbon Nanoframes and Hollow Carbon Nanocubes

AbstractNanocarbons are emerging at the forefront of nanoscience, and a wide variety of nanocarbons with unique structures have appeared over the past two decades. Currently, many carbon nanostructures have not been synthesized in the field of nanocarbons. The focus of this work is to present a new ideology and report two carbon nanostructures that have never been reported before. Inspired by the phenomenon of crystal growth, a new concept of thought is proposed. In brief, the diversity of crystal structures is utilized to enable surfactants to replicate their framework structures to create carbon nanomaterials with novel structures. In this work, carbon nanoframes (CNFEs) and hollow carbon nanocubes (HCNBs) synthesized by the 3‐(N,N‐dimethyldodecylammonio) propanesulfonate (SB3‐12)@NaCl self‐assembly strategy are used as proof of the ideology concept. It is shown that the prepared CNFEs have tunable dimensions (320–565 nm) and specific optical properties (fluorescence). The obtained HCNBs are 575 ± 20 nm in size and have fluorescent properties. It is found that changes in the concentration of SB3‐12 are a key driver of size changes, especially morphological evolution. It is believed that the ideology of this work provides a new entry point for the synthesis of carbon nanomaterials.

Conjugation of Doxorubicin and Carbon-based-nanostructures for Drug Delivery against HT-29 Colon Cancer Cells.

A drug delivery system is the method or process of administering a pharmaceutical compound to achieve a therapeutic effect in humans or animals. Such systems release the drugs at specific amounts in a specific site. The carbon based-nanomaterials have been actively used as drug carriers to treat various cancer. This study aimed to evaluate the cytotoxic effects of DOX-GO, DOX-OMC and DOXCNT in colon cancer cells (HT29). We reported platforms based on graphene oxide (GO), ordered mesoporous carbon (OMC) and carbon nanotubes (CNT) to conjugate with doxorubicin (DOX). The conjugation of DOX with carbon nanomaterial was investigated by UV-Vis spectroscopy, field emission scanning electron microscope (FE-SEM) and cyclic voltammetry (CV) methods. We showed that graphene oxide was a highly efficient matrix. Efficient loading of DOX, 89%, 78%, and 73.5% at pH 7.0 was seen onto GO, OMC and CNT, respectively. Upon pH 4. 0 after 15 h, 69%, 61% and 61% of DOX could be released from the DOX-GO, DOX-OMC and DOX-CNT, respectively, which illustrated the significant benefits of the developed approach for carbon nanomaterial applications. In vitro cytotoxicity analysis showed greater cytotoxicity of DOX/GO, DOX/OMC and DOX/CNT in comparison with GO, OMC and CNT against HT29 colon cancer cells with cell viability of 22%, 40% and 44% after 48 h for DOX-GO, DOX-OMC and DOX-CNT, respectively. The nanohybrids based on DOX-carbon nanomaterial, because of their unique physical and chemical properties, will remarkably enhance the anti-cancer activity.

In vitro cytotoxicity assessment of carbonaceous gels for bone marrow mesenchymal stem cells

The current work aimed to elucidate the potential applications of the carbonaceous gels and assess the in vitro cytotoxicity of these gels when suspended in a culture medium and exposed to bone marrow mesenchymal stem cells. Cellular viability, cell cycle distribution, apoptotic cell death, and mitochondrial membrane potential in bone marrow mesenchymal stem cells co-incubated with different concentrations of carbonaceous gels (0.1, 1, 10, 50, and 100μg/mL) were evaluated. Flow cytometry and immunofluorescence were used to investigate apoptosis and cell cycle distribution. The expression of associated apoptotic proteins was analysed using Western Blot. Although the co-incubation of carbonaceous gels did not significantly affect cell viability, high dosages (100μg/mL) of these gels led to cellular dysfunction. Specifically, cells exposed to high concentrations of these gels exhibited G2-phase arrest and increased levels of reactive oxygen species. However, the reported impacts did not cause considerable cell death. At the same time, carbonaceous gels did not significantly induce apoptosis. Compared to other carbon nanomaterials, carbonaceous gels' biotoxicity was relatively low, suggesting their potential for various biological applications. Nonetheless, caution should be exercised when considering the concentration of carbonaceous gels for future medical applications.

Exploring Graphdiyne - Dynamic Characterisation of the Surface Oxidation Mechanisms via ReaxFF-MD and Experiments

Graphdiyne (GDY) is an emerging two-dimensional carbon allotrope comprising unique sp1 and sp2 hybridisation, which has attracted extensive investigation into various applications, especially as battery component materials owing to its excellent electromechanical properties. However, GDY's thermal stability and oxidation behaviour have yet to be evaluated, which is crucial to safety in high-energy applications. The present study characterised the thermophysical properties of GDY via reactive molecular dynamics (MD-ReaxFF) and experimental measurement. The oxidation kinetics and decomposition behaviour were elucidated and benchmarked with graphene (GP) and graphyne (GY) to investigate the correlation between thermal stability and morphology of carbon nanomaterials. The simulation results revealed the initial oxidation mechanism of GDY sheets, where the cleavage of C-C bonds was observed at the acetylenic chain and could be identified as the weak spots of the structural stability. As for oxidation kinetics, GDY's experimental and numerical activation energy was found to be 173.1 and 133 kJ/mol, which is lower than 220.8 kJ/mol of GP. The current work pioneer investigated the thermal stability of GDY using both experimental and numerical approaches. Meanwhile, different oxidation mechanisms between GP and GDY were distinguished and demonstrated in detail.

Some features of experimental determination of localization length of charges in carbon nanomaterials for positive and negative magnetoresistance

This paper discusses features of experimental determination of localization lengths of charge carriers in carbon-based nanomaterials for the cases of positive and negative magnetoresistance in the hopping conduction regime. Magnetoresistance at a temperature of 4.2 K in reduced graphene oxide (RGO) and ternary nanocomposite PVDF/PANI/MWCNT film based on polyaniline (PANI, 4.8 wt%) and multi-walled carbon nanotubes (MWCNT, 10 wt%) distributed in the dielectric matrix of polyvinylidene fluoride (PVDF) was studied. The studied samples RGO and PVDF/PANI/MWCNT show positive and negative magnetoresistance, respectively. It is shown that in sufficiently weak magnetic fields, positive and negative magnetoresistances show a quadratic dependence on the applied field. The charge carrier localization length estimated from conductivity in weak magnetic fields agrees with data obtained in high electric fields without magnetic field.

Electrochemical Properties of Composites Based on Carbon Nanomaterials: A Review

Electrochemical Properties of Composites Based on Carbon Nanomaterials: A Review

Spectroscopic Differentiation of Structural Transitions from Carbon Nanobelts to Carbon Nanotubes.

In this study, simulated X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy were utilized to differentiate the early stage structures as carbon nanobelts (CNBs) evolved into carbon nanotubes (CNTs). The effects of edge type, length, and diameter on the spectroscopic characteristics of armchair and zigzag CNTs were examined. Variations in XPS spectra were found to correspond to changes in the bandgap, while Raman spectra provided distinct bands associated with specific structural features. Notably, in armchair CNTs, the C 1s XPS peak positions exhibited clear differences depending on the structure. Additionally, the Kekulé vibration band and other characteristic bands in Raman spectra varied with length and diameter, enabling differentiation of armchair CNT structures. Although the structural analysis of zigzag CNTs was challenging using XPS, Raman spectroscopy proved to be effective in distinguishing structural differences. This study lays the groundwork for future spectroscopic analyses, contributing to the broader understanding of nanocarbon materials such as CNBs and CNTs and their potential applications in advanced electronic materials.

Thermal Stability and Purity of Graphene and Carbon Nanotubes: Key Parameters for Their Thermogravimetric Analysis (TGA).

Thermal analysis is widely employed for the characterization of nanomaterials. It encompasses a variety of techniques that allow the evaluation of the physicochemical properties of a material by monitoring its response under controlled temperature. In the case of carbon nanomaterials, such as carbon nanotubes and graphene derivatives, thermogravimetric analysis (TGA) is particularly useful to determine the quality and stability of the sample, the presence of impurities and the degree of functionalization or doping after post-synthesis treatments. Furthermore, TGA is widely used to evaluate the thermal stability against oxidation by air, which can be, for instance, enhanced by the purification of the material and by nitrogen doping, finding application in areas where a retarded combustion of the material is required. Herein, we have evaluated key parameters that play a role in the data obtained from TGA, namely, gas flow rate, sample weight and temperature rate, used during the analysis. We found out that the heating rate played the major role in the process of combustion in the presence of air, inducing an increase in the temperature at which the oxidation of CNTs starts to occur, up to ca. 100 °C (from 1 °C min-1 to 50 °C min-1). The same trend was observed for all the evaluated systems, namely N-doped CNTs, graphene produced by mechanical exfoliation and N-doped reduced graphene samples. Other aspects, like the presence of impurities or structural defects in the evaluated samples, were analyzed by TGA, highlighting the versatility and usefulness of the technique to provide information of structural aspects and properties of carbon materials. Finally, a set of TGA parameters are recommended for the analysis of carbon nanomaterials to obtain reliable data.

Carbon quantum dots in breast cancer modulate cellular migration via cytoskeletal and nuclear structure

Carbon nanomaterials have been widely applied for cutting edge therapeutic applications as they offer tunable physio-chemical properties with economic scale-up options. Nuclear delivery of cancer drugs has been of prime focus since it controls important cellular signaling functions leading to greater anti-cancer drug efficacies. Better cellular drug uptake per unit drug injection drastically reduces severe side-effects of cancer therapies. Similarly, carbon dots (CDs) uptaken by the nucleus can also be used to set-up cutting edge nano delivery systems. In an earlier paper, we showed the cellular uptake and plasma membrane impact of combustion generated yellow luminescing CDs produced by our group from fuel rich combustion reactors in a one-step tunable production. In this paper, we aim to specifically study the nucleus by establishing the uptake kinetics of these combustion-generated yellow luminescing CDs. At sub-lethal doses, after crossing the plasma membrane, they impact the actin and microtubule mesh, affecting cell adhesion and migration; enter nucleus by diffusion processes; modify the overall appearance of the nucleus in terms of morphology; and alter chromatin condensation. We thus establish how this one-step produced, cost and bulk production friendly carbon dots from fuel rich combustion flames can be innovatively repurposed as potential nano delivery agents in cancer cells.

An updated review on carbon nanomaterials: Types, synthesis, functionalization and applications, degradation and toxicity

Abstract As carbon-based nanomaterials have such remarkable physical, chemical, and electrical capabilities, they have become a major focus of materials science study. A thorough examination of several carbon nanomaterial varieties, such as carbon nanotubes, graphene, fullerenes, and carbon nanodiamonds, is given in this review work. These materials all have distinctive qualities that qualify them for particular uses. This work starts by examining the synthesis processes of these nanomaterials, outlining the ways by which they are made and the variables affecting their ultimate characteristics. The specific features of each kind of carbon nanomaterial will then be briefly discussed in this study, along with their size, structure, and special physical and chemical properties. These materials have a wide range of possible uses in several fields. They are employed in the electronics industry to fabricate sensors, high-speed transistors, and other devices. Their high surface area and electrical conductivity make them useful in energy storage devices like supercapacitors and batteries. They are applied to environmental remediation and water purification in environmental science. They are employed in biomedicine for biosensing, bioimaging, and medication delivery. Notwithstanding the encouraging uses, the large-scale synthesis and functionalization of carbon nanomaterials present several difficulties. This review discusses the importance of carbon nanomaterials by studying their multifaceted properties and potential applications in industries. The novelty of this work lies in its detailed examination of the degradation and toxicity of these materials, which is essential for their safe integration into various technological and biomedical applications. By thoroughly analysing recent experimental results, this review aims to bridge the gap between fundamental research and practical applications.

Carbon Nanomaterials in Seed Priming: Current Possibilities

Carbon Nanomaterials in Seed Priming: Current Possibilities

Carbon nanomaterials for efficient oxygen and hydrogen evolution reactions in water splitting: A review

Water splitting has gained significant attention as a means to produce clean and sustainable hydrogen fuel through the electrochemical or photoelectrochemical decomposition of water. Efficient and cost-effective water splitting requires the development of highly active and stable catalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Carbon nanomaterials, including carbon nanotubes, graphene, and carbon nanofibers, etc., have emerged as promising candidates for catalyzing these reactions due to their unique properties, such as high surface area, excellent electrical conductivity, and chemical stability. This review article provides an overview of recent advancements in the utilization of carbon nanomaterials as catalysts or catalyst supports for the OER and HER in water splitting. It discusses various strategies employed to enhance the catalytic activity and stability of carbon nanomaterials, such as surface functionalization, hybridization with other active materials, and optimization of nanostructure and morphology. The influence of carbon nanomaterial properties, such as defect density, doping, and surface chemistry, on electrochemical performance is also explored. Furthermore, the article highlights the challenges and opportunities in the field, including scalability, long-term stability, and integration of carbon nanomaterials into practical water splitting devices. Overall, carbon nanomaterials show great potential for advancing the field of water splitting and enabling the realization of efficient and sustainable hydrogen production.

Detection of Tert-Butylhydroquinone in Edible Oils Using an Electrochemical Sensor Based on a Nickel-Aluminum Layered Double Hydroxide@Carbon Spheres-Derived Carbon Composite.

Phenolic antioxidants such as tert-butylhydroquinone (TBHQ) can prolong the shelf life of edible oils by delaying the oxidation process. The excessive use of TBHQ can damage food quality and public health, so it is necessary to develop an efficient TBHQ detection technique. In this work, nickel-aluminum double hydroxide (NiAl-LDH) was grown on glucose carbon spheres (GC), which formed porous carbon nanomaterials (named NiAl-LDH@GC-800) after pyrolysis at 800 °C. The successful synthesis of the material was verified by scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The obtained NiAl-LDH@GC-800 was dopped onto a glass carbon electrode to prepare an electrochemical sensor for TBHQ. The synergistic effect of porous carbon and Ni metal reduced from NiAl-LDH by high-temperature calcination accelerated the electron transfer rate and improved the sensitivity of the sensor. The prepared sensor showed a low limit of detection (LOD) of 8.2 nM, a high sensitivity (4.2 A·M-1), and a good linear range (20~300 µM) in detecting TBHQ. The sensor was also successfully used for TBHQ detection in edible oils, including chili oil, peanut oil, and rapeseed oil.

Advanced Hydrogels: Enhancing Tissue Bioengineering with RGD Peptides and Carbon Nanomaterials.

The advancement of tissue engineering (TE) is driven by the development of scaffolds that mimic the mechanical, spatial, and biological environment of the extracellular matrix (ECM), crucial for regulating cell behavior and tissue repair. Hydrogels, 3D networks of polymer chains, are particularly suited for TE due to their high biocompatibility, ability to mimic tissue water content, facilitate cell migration, sustain growth factor release, and offer controllable physical properties. However, hydrogels mimicking the ECM often face challenges related to cell adhesion due to the absence of specific receptors. This issue can be addressed by incorporating ECM components into the polymer matrix, such as the peptide sequence arginine-glycine-aspartic acid (RGD), known for its role in cell adhesion. Additionally, carbon nanomaterials (CNMs) offer unique physicochemical properties that can improve scaffold-cell interactions. Despite the potential benefits, there are limited reports on their combination. RGD-CNM hydrogels enable a more accurate emulation of the natural cellular environment, enhancing tissue engineering applications. This hybrid approach may promote robust cell adhesion along with exceptional mechanical and electrical properties. This review outlines the potential benefits of these hybrid scaffolds and their synergistic potential, aiming to inspire new research directions in this innovative field.