Carbon nanobud

{{too technical|section|date=November 2022}}

Carbon nanobuds (CNBs) have some of the properties of carbon nanotubes, such as one-dimensional electrical conductivity, flexibility and manufacturing adaptability, as well as some of the chemical properties of fullerenes. Examples of these properties include ability to engage in cycloaddition reactions and can easily form the chemical bonds capable of attaching to other molecules with complex structures. CNBs have a much higher chemical activity than single-walled carbon nanotubes (SWCNTs).Albert G. Nasibulin Ilya V. Anoshkin, Prasantha R. Mudimela, Janne Raula, Vladimir Ermolov, Esko I. Kauppinen, "Selective Chemical Functionalization of Carbon Nanobuds," Carbon 50, no. 11 (2012).

CNBs have been shown to have electronic properties that differ from those of fullerenes and carbon nanotubes (CNTs). CNBs exhibit lower field thresholds, higher current densities, and electric field emissions than SWCNTs. The chemical bonds between the nanotube's wall and the fullerenes on the surface can lead to charge transfer between the surfaces. The presence of fullerenes in CNBs leads to smaller bundle formation and higher chemical reactivity.{{cite journal | last1 = Ahangari | first1 = M. Ghorbanzadeh | last2 = Ganji | first2 = M.D. | last3 = Montazar | first3 = F. | year = 2015 | title = Mechanical and Electronic Properties of Carbon Nanobuds: First-Principles Study | journal = Solid State Communications | volume = 203 | pages = 58–62 | doi = 10.1016/j.ssc.2014.11.019 | bibcode = 2015SSCom.203...58G }} CNBs can engage in cycloaddition reactions and form chemical bonds attaching molecules with complex structures, due to the greater availability of CNB surface to the reactants, the presence of π-conjugated structure and 5-atom rings with excess pirimidization energy. Formation energy indicated that the preparation of CNBs is endothermic, meaning that it is not favorable to create.{{cite journal | last1 = Seif | first1 = A. | last2 = Zahedi | first2 = E. | last3 = Ahmadi | first3 = T. S. | year = 2011 | title = A Dft Study of Carbon Nanobuds | journal = The European Physical Journal B | volume = 82 | issue = 2| pages = 147–52 | doi = 10.1140/epjb/e2011-20139-5 | bibcode = 2011EPJB...82..147S | s2cid = 121728071 }}

All CNBs can conduct electricity, regardless of whether the single-walled CNT is a metallic or semiconducting base. The band gap of carbon nanobuds is not constant. It can change through the size of the fullerene group. The attachment of C₆₀ added to the armchair orientation of the SWCNT opens up the band gap. On the other hand, adding it to a semiconducting SWCNT could introduce impurity states to the band gap, which would reduce the band gap. The band gap of CNBs can also be modified by changing the density of the carbons of the C₆₀ attached to the sidewall of the SWCNT.Xiaojun Wu and Xiao Cheng Zeng, "First-Principles Study of a Carbon Nanobud," ACS Nano 2, no. 7 (2008)

Two structures of CNBs are ferromagnetic in their ground state, and two are nonmagnetic.Min Wang and Chang Ming Li, "Magnetic Properties of All-Carbon Graphene-Fullerene Nanobuds," Physical Chemistry Chemical Physics 13, no. 13 (2011). The attached C₆₀ molecule on the surface of the CNTs gives more space between the nanotubes-and adhesion between the single-walled CNTS can be weakened to prevent the formation of tight bundles of CNTs. Carbon nanobuds can be used as molecular support to prevent the matrix from slipping into composite materials and increasing their mechanical strength.

The stability of CNBs depends on the type of carbon bond that is dissociated in the cycloaddition. It has been shown that carbon atoms of the SWCNT near the fullerene C₆₀ molecule were pulled outward from the original wall surface due to the covalent bonding with cycloaddition between the fullerene and nanotube; in addition, their bonding was transformed from sp² to sp³ hybridization. An analysis using Raman scattering spectroscopy shows that the CNB sample had stronger chemical modification compared to CNTs. It indicates that there is a carbon sp³ hybridization that occurs after the chemical addition creation of CNBs.

The single wall carbon nanotubes can react with fullerenes in the presence of water vapor or carbon dioxide. It produces a covalently linked material that looks similar to buds on a tree branch, hence the name "Nanobud".Anisimov, Anton. "Aerosol Synthesis of Carbon Nanotubes and Nanobuds.". (2010).

The nanobuds form in abundance at 45ppm of water vapour and higher. However, above 365ppm, the reaction will give a higher number of inactive catalyst particles in lieu of the nanobud.

• Nanobud

{{Commons category|Carbon nanobuds}}

{{reflist}}

{{Allotropes of carbon}}

{{DEFAULTSORT:Carbon Nanobud}}

Category:Carbon nanotubes

Category:Articles containing video clips