Читать книгу Nano-Technological Intervention in Agricultural Productivity - Javid A. Parray - Страница 10

Two key NP groups based on carbon are fullerenes and carbon nanotubes (CNTs). Fullerenes contain globular hollow cage nanomaterials, similar to allotropic carbon forms. Their electrical conductivity, high power, structure, electron affinity, and flexibility have created considerable commercial interest [11]. Pentagonal and hexagonal C‐ units were arranged in these materials while each carbon was hybridized. The illustration in Figure 1.1 shows some of the well‐known 7.114 and 7.648 nm C₆₀ and C₇₀ fullerenes. The long, tubular CNTs have a diameter of 1–2 nm [12]. This can be predicted as metallic or semiconducting based on their telicity diameter [13]. Single, double, or multiple walls may be rolling sheets labelled single‐walled nanotubes (SWNTs), double‐walled nanotubes (DWNTs), or multi‐walled carbon nanotubes (MWNTs), respectively. They are commonly synthesized by carbon precursor deposition, particularly atomic carbons, which are vaporized by a laser or electric arc through metal particles. Recently, they have been synthesized using the chemical vapour deposition (CVD) technique [14]. Because of their specific physical, chemical, and mechanical characteristics, these materials are widely used in industrial applications, not only in pristine form but also in nanocomposites such as fillers [15], active gas adsorbents for the remediation of the environment [16], and, in general, for various inorganic and organic catalysts [17].