Carbon-Based Nanomaterials

Carbon-based nanomaterials (CNMs) have different structures, such as tube-like, spherical, horn-like, or ellipsoidal. They are mainly classified into three types of dimensionality: zero-dimensional, one-dimensional, and two-dimensional. CNMs show unique chemical, biological, optical, thermal, and mechanical properties. CNMs can be synthesized and tailored toward smart materials with characteristic applications. Currently, CNMs have attracted the interest of many researchers because of their diversified shapes and applications. Physicochemical parameters responsible for toxicity, such as size, shape and morphology, surface charge, composition, coatings, surface roughness, aggregation, and biological and chemical reactivity, are required to monitor the properties of CNMs. This chapter summarizes the types, synthesis, characterization, challenges of fabrication, current research trends, future aspects, toxicity, and environmental impacts of CNMs and their regulatory bodies, risk assessment, and mitigation, emphasizing their applications.

Graphene, a nanomaterial, is recognized as a two-dimensional (2D) carbon form, one of the universe's most prevalent elements. Despite its short history since its discovery, it exhibits extraordinary thermal, electrical, optical, and mechanical properties thanks to its high surface area, high electron mobility, biocompatible structure, and high adsorption capacity. These characteristics enable graphene and graphene-based nanomaterials to be remarkable in a variety of applications. According to the application area, the desired properties should be considered in the choice of synthesis method. Graphene synthesis methods are basically divided into the top-down method, which is based on the principle of exfoliation of layers, and the bottom-up method, which is based on the principle of layer growth. While synthesis methods provide a range of dimensional, physical, chemical, and morphological properties, these attributes are assessed using diverse characterization techniques, including X-ray photoelectron spectroscopy, Raman spectroscopy, X-ray diffraction, transmission electron microscopy, Brunauer–Emmett–Teller analysis, and thermogravimetric analysis. Graphene-based nanomaterials exhibit significant potential in catalyst application, aiding in air and water purification as well as water splitting for H₂ production due to their remarkable adsorption capacity. Moreover, they can also be used in energy storage because of their high electron mobility and conductivity and in various biomedical application areas because of their biocompatible structure. Looking ahead, these graphene-based nanomaterials hold significant promise, offering numerous technological opportunities in the future. This section initially highlights the structure and brief history of graphene, followed by examinations of the production processes, characterization procedures, and application fields for graphene-based nanomaterials.

Carbon nanotubes, which resemble graphite and diamond in their interesting chemical and physical characteristics, have an unusual atomic structure. Recent discoveries of different sorts of these structures have sparked research into the use of carbon nanostructures in several domains. They could be useful in the domains of genetics, medicine, and drug delivery. Currently, a variety of methods, including functionalization, filling, doping, and chemical modification, can be used to create carbon nanotubes (CNTs). Individual CNTs may now be identified, distinguished, and controlled. The reactive capacity of carbon nanotubes is greatly influenced by factors including structure, dimension, charge on the surface, distribution of sizes, surface chemistry, aggregation state, and sample purity. In addition, the strength and flexibility of carbon nanotubes make them potentially helpful for modifying various minuscule structures, signifying that they will play a significant role in the advancement of nanotechnology. This chapter's major objective is to examine all of the potential uses of CNTs for improving human health, with an emphasis on nano carriers and biological applications in particular. The first focus of this chapter is on the fundamental characteristics of CNTs, and it is then broadened to detail their synthesis methods and the many difficulties associated with their functioning, dispersion, and toxicity. Our discussion also places a strong emphasis on the future possibilities for these young disciplines of study.

Functionalized carbon nanomaterials are emerging as novel and innovative biomaterials with several applications in different research and biological sciences. The utilization of carbon-based nanoparticles is due to their intensive strength, stiffness, and property to get functionalized via different forms of reaction such as amidation and esterification of the nano-based particles. Furthermore, based on their size and structure, these carbon-based nanomaterials are characterized in different forms like one-dimensional, two-dimensional (Carbon nanotubes, Graphenes), and three-dimensional (Dendrimers). CNTs are nano-carriers in various biological, cancer diagnosis, and therapy applications. The potential efficacy and enhanced functional properties are due to their capability to move across membranes of biological systems and cause relatively low cytotoxicity. Recent advancement in nanotechnology has brought about the formulation of more effective nanocomposites, which have proven activity in bioremediation biomedical applications such as bio-imaging, biosensors, disease diagnostics, and pesticide management. This chapter focuses on functionalizing carbon nanoparticles and their role in different fields.

Carbon nanotubes (CNTs) are allotropes of carbon having a diameter in the nanometer range. The carbon nanotubes are differentiated by the design of graphite during its creation process. Smart carbon nanomaterials include carbon nanotubes (CNTs) with graphene, fullerene, carbon quantum dots (CDs), and mesoporous carbon nanomaterials (CNMs), which affect plant growth. CNMs have been shown to penetrate seed coatings, enter plant cells, and shift to various parts of the plant. Exposure reduces seed germination, root growth, and root architecture. CN inhibits seeds’ growth and alters plants’ genetic, biochemical, molecular, nutritional, and genetic levels. Using carbon-based nanomaterials is an ideal way to promote resistance to different stress levels in tomatoes and other crops. Antioxidants are part of the plant antioxidant defense system and are regarded as proteins. CNMs, such as carbon nanotubes, are known to induce the formation of antioxidant enzymes that produce protein accumulation. All these aspects have been thoroughly reviewed in this chapter, focusing on the recent updates on the role of CNMs in preventing or delaying plant growth. Concluding remarks have been added to propose future directions of research on the CNM plants interaction and also to sound a warning on the use of CNMs in agriculture.

Global agricultural systems are facing a lot of challenges of reduced crop yield, continuous decline in agricultural land, scarcity of irrigation water, and continuously changing climatic conditions. Agriculture, as a monoculture practice, has also to face the continuous occurrence of plant disease and increasing attack of resistant plant pathogenic microbes. The current treatments for killing plant pathogenic microbes are not environmentally friendly and sometimes fail to protect plants. The scientific and farming community is looking at nanotechnology as a potential alternative. Although many nanotechnological tools have been reported as potential weapons to render plant protection, carbon nanoparticles have recently gained attention. Their non-toxic attitude, environmental acceptability, and ability to possess biocidal properties against a wide range of plant pathogenic microbes make them superior to other nanoparticles. They kill the host cell by rupturing the cell membrane and penetrating the fungal hyphae, followed by the precipitation of genetic material. The multifarious approach reduces the chances of resistance in pathogenic microbes. In the current chapter, we have discussed different types of nanomaterials finding their origin in carbon and their plant protective role during various diseases. We have also tried to highlight the potential mechanism governing their biocidal nature.

Carbon nanomaterials are new and adaptable tools that can be used to improve many areas of plant growth and development, such as plant physiology, morphology, and the generation of primary and secondary metabolites. Nanotechnology has advanced and pioneered in science and technology over the past few years with the potential to change technologies in business, medicine, and agriculture. Carbon-based nanomaterials include semiconductors, zero-valent metals, quantum dots, nanopolymers, and dendrimers, with different properties such as nanofiber, nanowire, and nanosheets. Carbon-based nanomaterials are beneficial for plant growth, development, and protection against abiotic stress such as drought, high soil salinity, heat, cold, and other oxidative stress. The potential application of carbon nanomaterials, such as carbon nanotubes, graphene, and carbon nanodots, is increasing in plant development. These materials with unique properties have drawn much attention, which has led to the current large-scale expansion of industrial production. Regardless of the application area, this is also linked to an upward trend in the purposeful or accidental release of carbon nanoparticles into the environment, where it is still difficult to forecast how these materials may affect living things. The various kinds of carbon-based nanomaterials, the production methods, and the current developments in agricultural and environmental approaches have been covered in this chapter. The important information on the use of carbon nanoparticles is summarized, as is the current state of research pertaining to the effect of carbon nanomaterials on plant growth and development.

Carbon nanotubes are cylindrical structures made of carbon that have diameters as small as nanometers and lengths that range from micrometers to millimeters. They are widely sought after in a variety of sectors, including herbicide detection and cleanup, because of their exceptional qualities, which include excellent strength, stiffness, and outstanding thermal and electrical conductivity. Carbon nanotubes may be produced using arc discharge, template synthesis, laser ablation, and chemical vapor deposition. Carbon nanotubes have distinctive characteristics that benefit them in several applications, such as identifying herbicides. Due to their heightened sensitivity, these detectors are capable of effectively detecting low levels of substances in water and soil. Carbon nanotubes (CNTs) have versatile applications in several sensing systems, including electrochemical and optical sensors. They possess a relatively low cost and are easily manufactured, making them a desirable choice for sensor applications. Carbon nanotubes can remove herbicides from soil or water by adsorption, effectively minimizing environmental pollution. Carbon nanotubes (CNTs) may serve as a photocatalyst for the degradation of herbicides. This process involves the generation of electrons and holes, which then interact with herbicide molecules, breaking them down into non-toxic substances. In addition, carbon nanotubes (CNTs) may serve as electrodes in the electrochemical breakdown of herbicides. To summarize, using carbon nanotubes to detect and remove herbicides is a lucrative field of study that has promise for its possible applications in agricultural and environmental conservation. By investigating the properties of carbon nanotubes and evaluating different detection and remediation strategies, researchers can develop effective and sustainable solutions for herbicide contamination.

Carbon nanomaterials (CNs) possess unique physical, chemical, and physiological properties that make them highly valuable as carriers for biologically important molecules. However, their use is limited due to potential health and environmental effects. Nevertheless, CNs exhibit great potential in drug delivery owing to their high biocompatibility and surface area. Fullerenes, carbon nanotubes, graphenes, carbon nanodiamonds, porous carbon, and carbon dots are all CNs with broad applicability in drug delivery due to their small size and biological activity. Additionally, they can be customized with targeting ligands to deliver drugs to specific diseased cells or tissues and improve drug stability and solubility, resulting in better therapeutic outcomes. Recently, functionalized CNs with efficient drug-loading capacity, biocompatibility, and immunogenicity have been developed. These CNs have a high surface area, multifunctional surface chemistry, and excellent optical activity. Enzymatic degradation, surface modification, biological interactions, and biocorona play critical roles in achieving effective drug delivery. Recent advancements in carbon-based drug delivery hold the potential to improve disease treatment. CNs can be customized with bioactive peptides, proteins, nucleic acids, and drugs to create composites with low toxicity and high pharmaceutical efficacy. This chapter delves into the potential of CNs in drug delivery for various human diseases, including cancer, neurodegenerative conditions, tuberculosis, fungal infections, and other issues.

Biomedical applications of nanomaterials have gained attention because of their pivotal role in the improvement of human health. As compared to bulk material, nanomaterials have improved diagnostic and therapeutic applications. Carbon-based nanomaterials have remarkable potential for biomedical applications like biosensing, drug delivery, and gene therapy. Carbon-based one-dimensional (1D) and two-dimensional (2D) materials have excellent thermal, mechanical, and optical properties and possess structural diversity. Carbon has several interesting allotropes, like carbon nanotubes (CNTs), graphene oxide (GO), and graphene quantum dots (GDQs). These allotropes have been associated with numerous biological applications like biosensing and drug delivery. This chapter explores the biomedical applications of 1D and 2D carbon-based nanomaterials, including CNTs, graphene, GO, and reduced graphene oxide (RGO). The structural features and their specific applications in the biomedical field have been elaborated, taking examples from the literature. Potential toxicity risks on living organisms and the environment are also discussed, along with their applications. It is pertinent to comprehend their interaction with living systems to use them for biomedical applications.

In recent times, there has been a surge in the use of nanomaterials within biomedical. These materials have gained significant interest for their potential in several applications, including the development of artificial organs and tissues, drug delivery systems, and gene therapy. This increasing interest may be attributed to the unique properties of nanomaterials, namely their decreased dimensions and expanded surface area. Graphene and its derivatives have garnered significant attention across various areas, with a particular emphasis on biomedical applications. This preference stems from the exceptional structural, mechanical, optical, thermal, and electrical properties of graphene and its substantial surface area. These characteristics facilitate efficient and effective drug-loading processes. The use of graphene and its derivative materials in biomedical settings has significant importance in several domains, including tissue engineering, biosensor applications, and gene transfer, alongside its established role in controlled drug release applications. In this section, drug delivery and tissue engineering issues are specifically addressed. Graphene and its derivatives have exceptional characteristics as drug delivery carriers, rendering them very promising for applications involving materials with superior loading efficiency, targeting capabilities, imaging capabilities, sensing abilities, and stimulus-sensitive release qualities. These materials, which also aid in the restoration of the extracellular matrix or provide structural reinforcement, enhance the adhesion, proliferation, survival, and derivatives of stem cells, hence playing an important role in tissue engineering. The pre-use modification of graphene and its derivative-based materials used in biomedical implementations is crucial for mitigating concerns with “toxicity” and “biosafety,” in addition to the many advantages they provide.

Fungi are eukaryotic microorganisms, unicellular or multicellular, and several species are responsible for dormant/mild/life-threatening clinical implications in humans, animals and plants. The current chapter identifies the global burden of fungal infections and prospects for the utility of carbon nanomaterials in improving treatment regimes for the most prevalent fungal infections in humans. Major hurdles in clinically addressing fungal infections are drug resistance, metabolic and gene level homology of the fungi with humans leading to off-target effects, and lastly poor pharmacokinetics of the known anti-fungals. Carbon nanomaterials have emerged as promising candidates for drug and gene delivery due to their unique physicochemical properties, including high surface area, tunable surface chemistry, and biocompatibility. We have described in detail the recent literature wherein carbon nanomaterials–carbon nanotubes, carbon nanodots, graphene and graphene oxide, and fullerene are elaborated in terms of their properties suitable for drug and gene delivery, functionalization and efficacy in addressing fungal infections. The applications of carbon nanomaterials in addressing fungal infections via improved drug pharmacokinetics, controlled/sustained release of drug and improved efficacy due to synergistic effect with anti-fungal drugs has been elaborated. Lastly we have discussed the challenges of using carbon nanomaterials in anti-fungal regimes in terms of optimization required for drug loading and release kinetics, safety considerations and potential toxicity, and regulatory hurdles for translating carbon nanomaterial based interventions.

Carbon nanotubes (CNTs) are one of the most studied carbon-based materials. Due to their distinct physicochemical characteristics, CNTs can have a variety of biomedical applications. However, their toxicity is a significant issue with CNTs’ utilization in biomedical applications. Hence, many research groups are still focusing on this problem with carbon nanotubes. Functionalization of CNT improves the application of CNTs in the pharmaceutical area. Due to their distinctive qualities, including their high surface area, extraordinary mechanical strength, and great biocompatibility when suitably modified, functionalized CNTs have drawn a lot of attention in biomedical research. Here, in this chapter, we present a brief overview of carbon nanotubes and the key synthesis techniques. Further, the chapter also describes how functionalized CNTs are used in biomedicine and the variables and mechanisms impacting their toxicity. Due to their unique combination of mechanical, optical, and electrical properties, carbon nanotubes have attracted attention for use in a wide range of biomedical applications, including drug delivery, gene therapy, biosensors, and tissue engineering.

Globally, air pollution is a huge problem that impacts both the natural environment and the well-being of humans. The most recent advances in nanotechnology can help with potential remedies for the problems associated with air pollution and significantly improve the selectivity and efficacy of air cleansing systems, resulting in cost-effectiveness and more long-term performances. With the use of nanotechnology, air pollution could be reduced through a variety of methods, including using nanocatalysts, nanoadsorbents, nanosensors, and so on. The nanoparticles can adsorb or absorb several airborne pollutants. By employing the arrangement and size of the materials at the nanoscale form, nanotechnology is an innovative branch of science that may solve a wide range of environmental problems. For the reason of their benign nature, large surface area, ease of biodegradation, and mainly relevant environmental monitoring properties, carbon nanomaterials are distinctive. However, the use of carbon nanomaterials and nanotechnology is confronted with a number of difficulties, including production costs, toxicity, environmental hazards, and public acceptance. So, CNMs have advantages and disadvantages discussed in this chapter. The main emphasis of this chapter is the usage of CNMs in applications for air pollution remediation. Mainly, we discussed different types of carbon nanomaterial structures, properties, and removal mechanisms of different air pollutants.

Oil spills are a pressing issue as they impose a risk on the marine ecosystem and have severe economic and social consequences. Conventional methods for oil spill clean-up, such as mechanical containment and chemical dispersants, have limitations regarding efficacy, ecological footprint, and economic viability. Recently, the development of technology has revolutionized new possibilities for more efficient and sustainable oil spill clean-up strategies. Carbon nanomaterials have merged as a promising candidate among advanced materials due to their unique physiochemical properties and diverse applications. Carbon nanomaterials, including carbon nanotubes, graphene, carbon nanofibers, and carbon aerogels, display exceptional superhydrophobicity, chemical stability, high surface area, and mechanical strength, making them exceedingly suited for oil spill remediation. This chapter deals with a comprehensive overview of the carbon nanomaterials application in oil spill clean-up. Also, the various types of carbon nanomaterials and their unique properties that contribute to their effectiveness in oil sorption and separation have been discussed in detail.

The employment of nanotechnological tools is increasing at a very rapid pace in modern agricultural systems. Among a gamut of nanoparticles employed, carbon nanoparticles are also being explored as potential tools for increasing plant productivity. Due to their broad spectrum biocidal activity, they are projected as future biocontrol agents. However, the multifarious approach not only reduces the chances of resistance in pathogens but also puts forward the potential off-target effects of using these nanoparticles. The practice of agriculture is highly reliant on plant–microbe symbiotic relations. Therefore, nanoparticle accumulation in agricultural systems could disrupt this relationship. The interference of nanoparticles with the genetic material of plants and microbes can lead to the generation of mutant strains and serotypes with unpredictable outcomes.

Additionally, the repetitive exposure of rhizosphere microbes to carbon nanomaterials can lead to significant alterations in the rhizosphere microbiome that might significantly change plant productivity. In the current chapter, we have highlighted toxicity associated with the nanomaterials originating from carbon and potential harmful effects that might alter plant productivity. We have also tried to highlight the potential mechanism governing their off-target effects on the beneficial soil microbes.

Due to the world's rapidly increasing population and technological advancements, energy is needed. The world’s energy supply is anticipated to double by 2050. Nanotechnology has opened up new possibilities in materials science and engineering, specifically in the manufacture of new materials for efficient energy conversion and storage. Carbon nanomaterials (CBNMs) possess distinctive size and surface-dependent features, such as electrical, morphological, mechanical, and optical properties, that are advantageous for improving energy conversion and storage performance compared to traditional materials. Substantial progress has been made in creating high-performance energy conversion and storage devices such as solar cells, fuel cells, batteries, and supercapacitors. This book chapter focuses on the latest developments and improvements made to the effectiveness of electrode materials used in renewable energy storage and conversion systems by utilizing graphene, carbon nanotubes (CNTs), fullerenes, and nanohybrid fillers. These materials are exceptional candidates for solar cells because of their superior capacity for photon absorption, photovoltaic characteristics, producing photocarriers, and separating charge carriers to create heterojunction. The synthetic method, pore size and distribution, and specific surface area of these materials all impact the capacitance of supercapacitor and battery materials. Additionally, these nanomaterials’ high surface area and electronic conductivity enhance the rate of electrode reactions in fuel cells.