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Carbon Derivatives
Published in Sergey Edward Lyshevski, Nano and Molecular Electronics Handbook, 2018
The encapsulation of atoms inside hollow cages of fullerenes has proved a fascinating task ever since its discovery. Endohedral fullerenes (“endo” meaning within) are molecules where one or more atoms are captured inside the carbon cage. These were given the appealing designation M@Cn(n = 60, 70, and so on). Among the elements of the periodic table, electropositive metals such as cations, noble gas atoms, and group-V atoms have so far been encapsulated mainly by adding appropriate materials during the formation of the fullerenes in arc discharge and laser vaporization processes, applying high temperatures and high pressures to rare gas atoms, and other alternative methods such as atomic collisions in beams and ion implantation. However, group III-atoms (metals such as Sc, Y, La, Gd, etc.) have exclusively been encapsulated, not in C60, but in higher fullerenes such as C82, C84, etc. [5,6]. Since C60 has the highest productivity among all the fullerenes, Cn, when using the normal fullerene-production methods, it is an urgent issue today to develop an efficient method for synthesizing the endohedral C60 (M@C60) with high yields. When the production of M@C60 in large quantities is realized, many more experiments will be feasible and exciting results can be expected, leading to the development of innovative applications relating to nano- and molecular electronics.
Molecular and Carbon Nanoelectronics
Published in Sergey Edward Lyshevski, Nano- and Micro-Electromechanical Systems, 2018
Wide spectra of complex unsolved fundamental, applied, experimental, and technological problems remain. Many critical problems and issues have not even been addressed. This chapter introduces the reader to carbon-based nanoelectronics, nanodevices, interconnects, and nanofabrication, as well as possible topologies and architectures. It is difficult to fabricate carbon nanotubes with uniform and controllable electronic properties, and small changes result in totally distinct properties of carbon nanotubes, e.g., they become semiconducting, metallic, or semimetallic. Other solutions are needed, and fullerene-centered nanoelectronics is a possible candidate for nano-ICs. Different methods for fabrication of functional fullerenes and fullerene complexes have been developed. Correspondingly, novel nanoelectronic devices can be devised and made using fullerenes as building blocks. The encapsulation of distinct media in fullerenes leads to defining and controlling of electronic properties of endohedral fullerenes.
Magnetic Properties of Endohedral Fullerenes
Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020
Panagiotis Dallas, Reuben Harding, Stuart Cornes, Sapna Sinha, Shen Zhou, Ilija Rašović, Edward Laird, Kyriakos Porfyrakis
Small children, when presented with hollow toys, will instinctively try to place different kinds of objects inside them. Chemists behave in much the same way. Soon after fullerene molecules were discovered (Kroto 1985), it was natural to ask whether the empty space inside them could host other atoms or molecules. Within a decade, the answer was known to be “yes”. This class of molecules are the endohedral fullerenes.
Spectroscopy of astrophysically relevant ions in traps
Published in Molecular Physics, 2020
Recent developments in synthetic chemistry have seen the production of a few endohedral fullerenes containing rare gas atoms or small molecules inside the cage [91–94]. Electronic spectroscopy of and were recently reported [95,96], and high quality observational data is required to evaluate their possible presence in the ISM. Aside from these examples, many fullerenes and their analogues have not been isolated in macroscopic quantities. However, with developments in mass spectrometry that enable their gas phase synthesis (see, e.g. Ref. [97]), and the availability of sensitive methods for spectroscopic characterisation in low temperature traps, measurement of their electronic transitions is now feasible.
Effective field study of the magnetism and superconductivity in idealised Ising-type X@Y60 endohedral fullerene system
Published in Philosophical Magazine, 2019
Since its discovery in 1985 (Nobel Prize in 1996) [1], carbon-based nanocage structures such as fullerene, nanocapsules, nanopolyhedra, nanotubes, cones, cubes and onions have attracted a great interest due to its impressive properties and potential applications. Among all the structures, fullerene is the most abundant, and particular attention has been paid to the C60 compounds. C60 is most suited for doping as it is most stable among fullerenes. An endohedral fullerene (EF), which first evidenced by Heath et al. [2], is a structure that occurrence by atoms or small molecules doped inside of an empty fullerene cage. The unique core–shell structures of EFs make them more attractive and more useful than empty fullerenes. In physical, chemical and biological areas, EFs have attracted a great interest because of their fascinating properties such as drug delivery applications [3], photovoltaic devices [4] and quantum-information processing [5]. Recently, the physical and chemical properties of EF have been studied from both experimental [6–12] and theoretical points of view [13–19].
Electronic structure of hydroxylated La@C82 endohedral metallofullerene: implications on photovoltaic cells
Published in Molecular Physics, 2020
Z. N. Cisneros-García, David Alejandro Hernández, Francisco J. Tenorio, J. G. Rodríguez-Zavala
Here it is worth to mention that there is a lot of information on exohedrally functionalised non-endohedral fullerenes applied to photovoltaic devices [1, 18, 19]; however, fewer studies focus on endohedral fullerenes applied to solar cells [20]. It is well-known that endohedral fullerenes production is more difficult than non-endohedral fullerenes; nonetheless, the encapsulated atoms easily mofify the electronic structure. A good opportunity is offered by the prototypical endohedral fullerene, even more, when it can be multi-functionalised and varied its degree of coating [21]. This system is perfect for performing a systematic analysis of electronic structure variation with the number of hydroxyl groups and its implication in possible solar cells usage.