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The Impact of Carbon-Based Nanomaterials in Biological Systems
Published in Swamini Chopra, Kavita Pande, Vincent Shantha Kumar, Jitendra A. Sharma, Novel Applications of Carbon Based Nano-Materials, 2023
Leirika Ngangom, Kunal Sharma, Pankaj Bhatt, Nilay Singhand, Neha Pandey
Carbon is the sole and imperative element on the Earth and is ranked as the second component that is present in a human body comprising about 18% of the individual’s weight. The remarkable character of the carbon element is that its wide range of metastable stages can be arranged or formed around the intermediate surroundings. In addition to this, the function of carbon is vital as it forms a bond with the enclosing light components and also with itself despite the scarce amount available around the Earth’s crust, which is about 0.032% from the overall mass of the planet (Zhang et al. 2012, Marty et al. 2013). Therefore, the functional capability of carbon elements has bought a wide expansion in the field of biology and chemistry. In the current era, the study of carbon science is very contemporary, and in some research areas, such as engineering and technology, materials science, nanoscience, and carbon nanostructures, have carbon elements of various low dimensions comprising carbon nanotubes, graphene, and activated carbon (Geim et al. 2007, Titirici et al. 2015, Deng et al. 2016). There are different allotropic forms of carbon, namely graphite, buckminsterfullerene (smallest fullerene molecule), and diamond. Among the allotropes of carbon mentioned, the thermodynamically stable allotrope is graphite. It has a high thermal and electrical conductivity that makes it suited for use in various applications that demands high temperatures. Graphite is a crystalline form of carbon molecule and its atoms configured in a hexagonal
Graphene Synthesis, Characterization and Applications
Published in Amir Al-Ahmed, Inamuddin, Graphene from Natural Sources, 2023
Hamidreza Bagheri, Marzieh Fatehi, Ali Mohebbi
Carbon derives its name of the word carbo, and its meaning is charcoal (Bonaccorso et al., 2012). Carbon is significant element due to its significant electronic structure that allows for hybridization to shape up sp, sp2 and sp3 networks and, therefore, to form stable allotropes compared to other elements (Huang et al., 2011). Graphite is the most popular carbon allotropic, and it is a natural mineral. Carbon element was found out in the all known life forms (Wanno and Tabtimsai, 2014). Carbon individuality is established in several allotropes in that it happens. This element shows smoothness such as graphite in pencil, to hardest known element in diamond (Trivedi et al., 2019). The other allotropes of carbon are nanotubes, fullerenes, glassy carbon and amorphous carbon (Figure 10.1). The main parameters of carbon-based materials of various dimensionalities are given in Table 10.1. Forth suggested naming conventions are also given in Table 10.2. Indeed, the phrase graphene must be used for isolated monolayer hexagonally form that organized bonded of carbon in configuration of sp2 (Feriancikova and Xu, 2012). The term graphite oxide is the material in solid state, provided with oxidation of graphite to functionalize fundamental planes and enhance inter-layer spacing. The term graphene oxide is graphite oxide exfoliated form and it is usually provided with dispersing this very solvable material in an aqueous solvent. To end, reduced graphene oxide consequences from reduction of graphene oxide (GO) (Lee et al., 2008).
Application of Carbon Nanotubes in Cancer Vaccines as Drug Delivery Tools
Published in Loutfy H. Madkour, Nanoparticle-Based Drug Delivery in Cancer Treatment, 2022
CNTs are synthetic allotropes of carbon. Allotropy is described as the chemical elements’ ability to exist in more than one form. Three allotropic forms have been identified for carbon. The natural carbon allotropes include diamond, graphite (several layers of graphene), and amorphous carbon (non-crystalline form of carbon) [62]. The synthetic carbon allotropes that have been discovered include fullerene (sphere of carbon atoms) [63], graphene (single layer of graphite) [64], and CNT (cylinder consisting of rolled graphene layer(s)) (Figure 9.3) [65]. Morphologically, CNTs can be described as cylinders that are nanometers wide and nanometers to micrometers long, consisting of graphene rolled up in the form of single or multiple concentric layer(s) that are referred to as SWCNT or MWCNT, respectively [66].
Graphene-based electrodes for ECG signal monitoring: Fabrication methodologies, challenges and future directions
Published in Cogent Engineering, 2023
Rimita Dey, Pravin Kumar Samanta, Ram Pramod Chokda, Bishnu Prasad De, Bhargav Appasani, Avireni Srinivasulu, Nsengiyumva Philibert
Carbon is known as the materia prima of all living bodies. Carbon exhibits many complex, unusual behaviours. As a result of their bonding flexibility, carbon-based materials can be used to construct a wide variety of structures with different physical properties. Different dimensions of the structure are also responsible for different physical properties. Graphite and diamond are the well-known 3-dimensional structures of carbon. Other than diamond and graphite, there are other allotropes of carbon, such as graphene (2-dimensional), carbon nanotubes (1-dimensional) and fullerenes (0-dimensional). Graphene is theoretically the most studied 2-dimensional allotrope of carbon. In graphene, carbon atoms are organised in a planar hexagonal honeycomb-like structure, and it is considered the initial step for all calculations on fullerenes, carbon nanotubes and graphite.
Use of nanomaterial for asphalt binder and mixtures: a comprehensive review on development, prospect, and challenges
Published in Road Materials and Pavement Design, 2021
Prabin Kumar Ashish, Dharamveer Singh
A carbon nanotube is essentially made up of sheets of graphite (an allotrope of carbon) rolled up in a tubular structure with very high aspect ratio, significantly higher than any other existing material (Wang et al., 2009). CNT was firstly discovered and characterise by Iijima (1991). The diameter of CNT found to be as low as 0.4 nm to up to several hundred nanometres (Bai & Allaoui, 2003). CNT possess unique mechanical properties. For example, tensile strength for CNT has been reported anywhere in the range of 11 to 63 GPa (Yu et al., 2000a). The tensile failure strain of CNT has been reported as close to 5.5% (Yu, Files, Arepalli, & Ruoff, 2000b). Young’s modulus of CNT has been reported anywhere in the range of 15–50 GPa (Treacy, Ebbesen, & Gibson, 1996). Such an excellent mechanical property signifies CNT as an ideal choice for various structural purposes (Larsen-Basse & Chong, 2006; Steyn, 2009). Based upon the number of rolled graphene sheets, CNT can be divided into single wall CNT and multi-wall CNT, manufactured using mainly three different approaches namely (a) arc discharge method, (b) Chemical Vapour Deposition (CVD), and (c) laser ablation method (Rafique & Iqbal, 2011). Importantly, multi-wall CNT is stiffer, cheaper and produced at a larger scale, therefore, it can be considered as an obvious choice over single wall CNT for modification of asphalt binder (Steyn, Bosman, Galle, & van Heerden, 2013).
Spectroscopy of astrophysically relevant ions in traps
Published in Molecular Physics, 2020
In the 1985 experiment, radiation from the second harmonic of an Nd:YAG laser was used to produce carbon clusters from a rotating graphite disk. The neutral molecules were ionised in a helium expansion and detected via time-of-flight mass spectrometry. The results showed a distribution where, for mass-to-charge ratios (m/z) of greater than 480, only species containing an even number of carbon atoms were observed. Moreover, a slightly enhanced peak at , and also one at , was seen. These ‘clusters’ are now known as fullerenes, an allotrope of carbon in addition to the previously identified graphite and diamond. It was immediately recognised that this may have implications for the DIB enigma and, in 1987, Kroto highlighted the astrophysical importance of the singly charged cation C, writing ‘The present observations indicate that C might survive in the general interstellar medium (probably as the ion C) protected by its unique ability to survive processes so drastic that, most if not all, other known molecules are destroyed’ [68]. This conjecture was subsequently shown to be correct.