Synthesis Of Fullerenes Research Articles

Controlled Synthesis of C70 Fullerene Micro/Nanotubes

The physical features of the synthesis and further growth of C70 fullerene micro/nanotubes in the volume of an evaporating drop on a substrate surface have been studied. The morphological and optical characteristics of one dimensional C70 nanostructures have been determined. The possibility of controlling the geometric dimensions of the synthesized C70 tubes by changing both the concentration of C70 in the initial drop and the temperature of the substrate used was demonstrated experimentally.

Improving stability, mechanical and electronic properties of pentadiamond by doping with alkali or alkaline-earth metals: A first-principles investigation

Pentadiamond (PD), a recently proposed carbon allotrope, has garnered considerable attention owing to its unique covalent framework comprising both sp2 and sp3 carbon atoms. Despite its intriguing structure with potentially useful thermal, electronic and optical properties, PD is supposed to be thermodynamically very unstable, due to the strain imposed by adjacent pentagonal rings in the carbon framework, which poses a major concern for its practical production. Here, we employ first-principles simulations to demonstrate that inserting alkali or alkaline-earth metals into the bigger cavities of PD significantly enhances its thermodynamic stability. Moreover, the resulting doped materials exhibit high kinetic stability at high temperatures typical for synthesis of fullerenes and metallofullerenes. We systematically investigate the structures and the modulation of mechanical properties and electronic structures of metal-doped PDs. Most remarkably, beryllium is revealed to be the energetically most favorable dopant among the metals considered. Be-doped PD exhibits an increased shear and Young's moduli (by about 55.6 % and 44.4 %, respectively), along with a substantially reduced Poisson's ratio (from 0.23 to 0.14). Furthermore, doping with Be transforms PD from an indirect-gap material to a direct-gap semiconductor, narrowing the band gap from 3.58 eV to 2.67 eV. We hope these findings may stimulate the experimental endeavors to synthesize metal-doped PD materials and unlock their potential applications.

Классификация методов синтеза полигидроксилированных фуллеренов. Часть 1 — Одностадийные процессы

A complete analysis of the existing methods of synthesis of polyhydroxylated fullerenes using direct chemical interaction,as well as alternative methods of creation, in order to identify the optimal methods of production, for their implementation in various technological and biomedical fields is performed. The scientific literature of this field of research is summarized and classified, providing a comparative assessment of the efficiency and feasibility of practical implementation of the developed synthesis methods based on a comprehensive review of the data presented in the chemical literature.

60 Karbonlu Fullerenlerin Astrokimyasal İncelemesi

Fullerene, which is a carbon allotrope in nanolattice structure, was detected in the IR (infrared) band of ISM (interstellar medium) in 1985 before it was synthesized on earth. Fullerene synthesis, which brought the Nobel Prize to Kroto, Curl and Smalley in 1996, both contributed to the developments in the field of nanotechnology and the molecule's ISM discoveries were accelerated since it entered the astrochemistry literature as the largest molecule. Data from space telescopes since 2010 found that C60 is more present in planetary nebula regions. In the cosmic environment, C60's ability to be caged with He and other heavier elements allows it to be distinguished from PAHs (polycyclic aromatic hydrocarbons), which have a wide bandgap in their spectra. By combining observational, theoretical and laboratory data, synthetic spectra for He@C60+ (fullerene caged with He) can be generated and C60 regions can be detected in the interstellar medium.

Synthesis and characterization of fullerene modified with copper nanoparticles catalyzed C[sbnd]H bond activation as a sustainable and green catalyst for electro synthesis of benzothiazole derivatives

In this study, our focus was on synthesizing and characterizing a fullerene modified with copper nanoparticles. This modified fullerene catalyzes for the eco-friendly synthesis of benzothiazole 5(a-m) derivatives. These derivatives are obtained through the reaction of 2-iodoaniline 1(a-f), toluene 2(a-e), and Na2S resulting in good yields (89–94 %). The nanocomposite catalyst underwent thorough characterization using various analytical techniques, including Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM), Energy-dispersive X-ray spectroscopy (EDS), Brunauer–Emmett–Teller (BET), Thermogravimetric analysis (TGA), Ultraviolet (UV), X-ray photoelectron spectroscopy (XPS), Cyclic voltammetry (CVs) and X Ray Diffraction Analysis (XRD) spectroscopy. By utilizing this catalyst, we achieve a more environmentally friendly approach to synthesis, reducing the requirement for hazardous and toxic reagents, and minimizing waste generation through reusability. The products obtained in this study were characterized using melting point determination, 1HNMR spectroscopy, and CHN analysis. These analytical techniques were employed to establish the identity and purity of the synthesized compounds.

Water in Fullerenes

Abstract A water molecule fixed within [60]fullerene is the simplest form of water available in meatspace. It was first artificially made by us in 2011. Since then, anomalies of water molecules free from any hydrogen-bonding have been discovered in succession. In this account, we summarize the research progress in the past decade from the aspect of synthesis, derivatization, and reactivity of fullerenes with water inside as well as their quantum and classical dynamics.

Enabling efficient water desalination and mitigating membrane fouling by the novel two-dimensional fullerene with unlocking its electrostatic forces

Graphene-based two-dimensional (2D) materials are currently a prominent focus in membrane research, yet they face challenges related to precise perforation and regulation of interface activity. Recently, the successful synthesis of 2D fullerene (C60) (Meirzadeh et al., Nature 2023, 613, 71) has expanded the repertoire of available 2D materials. However, its potential for membrane separation remains unexplored until now. In this study, we propose, for the first time, the utilization of 2D C60 for water desalination, leveraging its natural pores to circumvent the perforation challenge and allowing for precise tuning of interface activity. By establishing quantitative relationships between water flux and various operating conditions, this theoretical work can be extrapolated to guide practical desalination processes. Through non-equilibrium molecular dynamics simulations, it demonstrates that pristine 2D C60 exhibits unparalleled water permeance and achieves 100% salt rejection, regardless of operating pressure or the types of salt ions. To enhance desalination performance, we further propose a rational design strategy using endohedral 2D C60 with a positively charged surface, which improves water permeance up to 29.3 L⋅cm−2⋅day−1⋅MPa−1 and simultaneously reduces crystallization and colloidal fouling on the membrane surface by unlocking electrostatic attraction and repulsion forces, respectively. The mechanism behind this exceptional performance is attributed to the existence of well-endowed nanopores that form a connected hydrogen bond network, enabling swift vertical flow of water through the channels. Our findings showcase the exciting prospects of the novel 2D C60 material and provide a compelling new approach to membrane-based desalination, with the potential to revolutionize membrane materials.

(Invited) Synthesis of Ion-Endohedral Fullerenes by Plasma Implantation

Endohedral metallofullerenes (EMFs), which are the hybrid materials consisting of fullerene cage and encapsulated metal(s), are one of the well-studied nanocarbon materials during the past 3 decades.[1] As a result of significant progress in the development of synthetic procedures and purification processes, a variety of different types of EMFs, such as mono-metallofullerenes, di-metallofullerenes and metal-cluster-fullerenes with various carbon-cage sizes, are currently available. We previously reported development of an efficient method to access EMFs, so-called plasma implantation.[2] This approach allowed us to achieve scalable synthesis of lithium-ion-encapsulated [60]fullerene Li+@C60 X−, a stable ionic form of lithium encapsulated fullerene. The compound can be regarded as “ion-endohedral fullerene” consisting of encapsulated ion, neutral fullerene cage and external counter anion X−, and it should not be categorized into general metallofullerenes because of its ion-pair structure. Despite the unique properties arising from its ionic natures, no other ionic metallofullerenes have been well studied so far.[3] For systematic and deeper studies on ion-endohedral fullerenes, we focused on Li+-endohedral [70]fullerene (Li+@C70) because C70 is the second abundant and therefore widely studied fullerene next to C60. The Li+@C70 was synthesized as PF6 − and TFSI− (TFSI=bis(trifluoromethanesulfonyl)imide) salts using our improved plasma implantation method followed by oxidative purification process. 7Li NMR spectrum showed a sharp singlet signal at −32.81 ppm (vs LiCl/D2O standard) indicating that the Li+ was encapsulated in the C70 cage. 13C NMR spectrum showed 5 aromatic peaks, which evidenced the defectless C70 structure. In addition to the NMR signals originated from the Li+@C70 core, 19F and 31P NMR spectra showed clear signals assigned to each external counter anion. The structure of Li+@C70 was unambiguously confirmed by X-ray crystal structure analysis of the TFSI− salt. The crystal structure showed encapsulation of Li+ by C70 cage as well as the 1:1 ion-paired structure of the cationic Li+@C70 core and external TFSI− anion.Moreover, we also performed collision experiments using sodium plasma to synthesize sodium-ion-endohedral [60]fullerene. Laser desorption ionization (LDI) mass spectrum of the crude products showed signals at m/z= 720 and 743 assignable to the molecular ion of empty C60 and the Na+@C60, respectively. The target compound was isolated as TFSI− salt by oxidative purification process followed by electrolyte-added HPLC. There was only a mass peak at m/z= 743 after the purification, which evidenced the complete removal of empty C60. 23Na NMR spectrum showed a sharp singlet signal at −59.6 ppm (vs NaCl/D2O standard), evidenced the formation of the target Na+@C60.

Multiply exo-Methylated Corannulenes.

The curved π-conjugated surface of bowl-shaped corannulene has been multiply methylated to form exo-di-, -tetra-, and -hexamethylated corannulenes. The multimethylations became possible through in-situ iterative reduction/methylation sequences that involve the reduction of corannulenes using sodium to form the anionic corannulene species, and the subsequent SN 2 reaction of the anionic species with reduction-resistant dimethyl sulfate. X-ray diffraction analyses, NMR, MS, UV-Vis measurements, and DFT calculations have revealed the molecular structures of the multimethylated corannulenes and the sequence of the multimethylation. This work has the potential to contribute to the controlled synthesis and characterizations of multifunctionalized fullerenes.

Pr@C82 Metallofullerene: Calculated Isomeric Populations

Relative equilibrium populations of the five lowest-energy isolated-pentagon-rule (IPR) isomeric structures of Pr@C82 under high-temperature fullerene synthesis conditions were calculated with the Gibbs energy terms based on molecular characteristics derived using density functional theory (DFT) treatments (B3LYP/6-31+G*∼SDD energetics and B3LYP/6-31G*∼SDD entropy). Two leading isomers were identified, major Pr@C2v;9-C82 and minor Pr@Cs;6-C82. The calculated isomeric relative equilibrium populations agreed with observations.

Development of Practical Synthetic Methods Utilizing O-X or N-X Species

In chemical species containing of oxygen-halogens and nitrogen-halogens bonds, the halogen substituents show versatile reactivities, because oxygen and nitrogen atoms have higher electronegativity than halogen elements except for fluorine. I have focused on such monovalent halogen species and developed various synthetic methods utilizing O-X and N-X bonds which involves ionic and radical reactions. In this account, I describe such practical synthetic methodologies, which are CO2 fixation to unsaturated alcohols and amines, oxidative homo- and cross-coupling reactions of aromatic amines, novel generation of nitrile oxides from aldoximes, synthesis of oxazole-fused C60, iodoamination of alkenes in water, diaziridination of secondary amines, diastereodivergent diamination of unactivated alkenes, practical aziridination of electron-deficient alkenes, selective synthesis of nitrogen-bridged fullerenes, and benzylic C-H amidation.

Pentagon-Fused Sumanenes on the Aromatic Peripheries en Route to the Bottom-Up Synthesis of Fullerenes

AbstractBowl-shaped π-conjugated sumanenyltriamines were successfully synthesized in a one-step reaction from bromomethylsumanene. This molecule represents an example of hemiazafullerene (C54N6 fragment) with six isolated pentagons. Its single-crystal X-ray structural analysis showed the formation of one-dimensional columnar structures incorporating chloroform. The hemifullerene (C30 fragment) was also synthesized when the nucleophile was changed to dimethylmalonate.

Features of the synthesis of fullerenes and their derivatives

The discovery of a new form of carbon was the great scientific breakthrough of the 20th century. Carbon is one of the most abundant elements on our planet. A molecule consisting of 60 carbon atoms was named a fullerene. Fullerene C60 is a molecule consisting of 20 hexagonal and 12 pentagonal rings with carbon atoms at their vertices, and has a high symmetry. The radius of C60 fullerene is 0.3512 nm, the length of the short bond separating the hexagons is 0.1391 nm, and the length of the long bond common to hexagons and pentagons is 0.1455 nm. The research was carried out at the NNLOT at KazNU. al-Farabi, where one of the main scientific areas of research is the creation of new types of materials based on carbon nanostructures, in particular fullerenes, as well as their application. A technique for the synthesis of fullerenes was created and developed for their practical application in various industries. A plant for the production of fullerenes based on the method of electric arc evaporation of graphite in a helium medium was launched. The features of the synthesis of fullerenes and their derivatives by the developed method were studied. The technology for obtaining fullerenes in an electric arc discharge at various current values (A) has been developed. Fullerene samples were obtained and analyzed at various current strengths (110A, 135A, 160A, 180A, 200A). The obtained samples were studied both by Raman spectroscopy and by electron and optical microscopy.

Microstructural, Optical, and Work Function Tuning of Fullerene (C60) Modified Zinc Oxide Films for Optoelectronic Devices

Here, we report the synthesis of pristine and fullerene (C60) modified zinc oxide (ZnO) films by the sol-gel method. Various compositions of C60 ranging from pristine to 0.25 wt%, 0.50 wt%, and 1.00 wt% have been chosen for the modification of ZnO film. The incorporation of C60 in pristine ZnO films modifies its structural, surface morphological, optical, and electrical properties. Structural characterization suggests that pristine and C60 modified ZnO films exhibit Wurtize crystal structure. Surface morphological characterization demonstrates that incorporation of C60 into ZnO leads to the formation of spherical nano-particles which varies on the doping of C60. The properties of C60 doped ZnO films show a reduction in the bandgap values from 3.11 eV to 2.73 eV with enhanced optical absorption and photoluminescence properties. Further, the surface potential and work function of pristine and C60 incorporated ZnO films, as investigated by Kelvin probe force microscopy (KPFM) show tuning of Fermi level in pristine and C60 modified ZnO films. The work function of the ZnO films changes from −4.38 eV to −4.46 eV on the incorporation of C60. The variations in work function may be due to reduced microstructural and localized defects offered during the incorporation of C60. Also, C60 modified ZnO Schottky diodes exhibited enhanced carrier mobility with better charge transport properties.

Effect of Metallic and Non-Metallic Additives on the Synthesis of Fullerenes in Thermal Plasma

The effect of metallic (Fe, Cu, Co, Ni, Ti) and non-metallic additives (Si, B) on the formation of fullerenes from graphite powders was studied in radiofrequency (RF) thermal plasma. The main component of the synthesized fullerene mixtures was C60, but higher fullerenes (C70, C82, and C84) could be detected as well. Fe and Cu additives increased the fullerene content in the soot. In contrast, the fullerene formation decreased in the presence of Ti, Si, and B as compared to the synthesis without additives. However, Ti and B addition enhanced the formation of higher fullerenes. We provide experimental evidence that decreasing the reactor pressure results in a lower yield of fullerene production, in accordance with thermodynamic calculations and numerical simulations published earlier. In the presence of titanium, a significant quantity of TiC was also formed as a by-product. The fullerene mixture synthesized with boron additives showed higher stability during storage in ambient conditions as compared to other samples.

Synthesis of Fullerenes from a Nonaromatic Chloroform through a Newly Developed Ultrahigh-Temperature Flash Vacuum Pyrolysis Apparatus.

The flash vacuum pyrolysis (FVP) technique is useful for preparing curved polycyclic aromatic compounds (PAHs) and caged nanocarbon molecules, such as the well-known corannulene and fullerene C60. However, the operating temperature of the traditional FVP apparatus is limited to ~1250 °C, which is not sufficient to overcome the high energy barriers of some reactions. Herein, we report an ultrahigh-temperature FVP (UT-FVP) apparatus with a controllable operating temperature of up to 2500 °C to synthesize fullerene C60 from a nonaromatic single carbon reactant, i.e., chloroform, at 1350 °C or above. Fullerene C60 cannot be obtained from CHCl3 using the traditional FVP apparatus because of the limitation of the reaction temperature. The significant improvements in the UT-FVP apparatus, compared to the traditional FVP apparatus, were the replacement of the quartz tube with a graphite tube and the direct heating of the graphite tube by impedance heating instead of indirect heating of the quartz tube using an electric furnace. Because of the higher temperature range, UT-FVP can not only synthesize fullerene C60 from single carbon nonaromatic reactants but sublimate some high-molecular-weight compounds to synthesize larger curved PAHs in the future.

Self-Assembly-Directed Organization of a Fullerene-Bisporphyrin into Supramolecular Giant Donut Structures for Excited-State Charge Stabilization.

Functional materials composed of spontaneously self-assembled electron donor and acceptor entities capable of generating long-lived charge-separated states upon photoillumination are in great demand as they are key in building the next generation of light energy harvesting devices. However, creating such well-defined architectures is challenging due to the intricate molecular design, multistep synthesis, and issues associated in demonstrating long-lived electron transfer. In this study, we have accomplished these tasks and report the synthesis of a new fullerene–bis-Zn-porphyrin e-bisadduct by tether-directed functionalization of C60 via a multistep synthetic protocol. Supramolecular oligomers were subsequently formed involving the two porphyrin-bearing arms embracing a fullerene cage of the vicinal molecule as confirmed by MALDI-TOF spectrometry and variable temperature NMR. In addition, the initially formed worm-like oligomers are shown to evolve to generate donut-like aggregates by AFM monitoring that was also supported by theoretical calculations. The final supramolecular donuts revealed an inner cavity size estimated as 23 nm, close to that observed in photosynthetic antenna systems. Upon systematic spectral, computational, and electrochemical studies, an energy level diagram was established to visualize the thermodynamic feasibility of electron transfer in these donor–acceptor constructs. Subsequently, transient pump–probe spectral studies covering the wide femtosecond-to-millisecond time scale were performed to confirm the formation of long-lived charge-separated states. The lifetime of the final charge-separated state was about 40 μs, thus highlighting the significance of the current approach of building giant self-organized donor–acceptor assemblies for light energy harvesting applications.

Front Cover: Regioselective Synthesis of Fullerene Tris‐adducts for the Preparation of Clickable Fullerene [3 : 3]‐Hexa‐adduct Scaffolds/Regioselective Preparation of Fullerene Bis‐adducts from Cleavable Macrocyclic Bis‐malonates (Eur. J. Org. Chem. 27/2021)

Front Cover: Regioselective Synthesis of Fullerene Tris‐adducts for the Preparation of Clickable Fullerene [3 : 3]‐Hexa‐adduct Scaffolds/Regioselective Preparation of Fullerene Bis‐adducts from Cleavable Macrocyclic Bis‐malonates (Eur. J. Org. Chem. 27/2021)

Regioselective Synthesis of Fullerene Tris‐adducts for the Preparation of Clickable Fullerene [3:3]‐Hexa‐adduct Scaffolds

AbstractMacrocyclic tris‐malonates incorporating cleavable di‐tert‐butylsilylene protecting groups have been prepared by a stepwise approach and used for the regioselective tris‐functionalization of C60. Fullerene tris‐adducts with an e,e,e addition pattern have been thus obtained. The bridging di‐tert‐butylsilylene protecting groups have been cleaved to liberate the terminal alcohol functions of the fullerene tris‐adduct. This key building block has been further functionalized to generate a clickable fullerene [3:3]‐hexa‐adduct scaffold allowing the successive introduction of two azide reagents.

Fullerene synthesis and modification of building materials with fullerenes C60 and C70

The article presents the results of the study of plasma chemical synthesis fullerenes using composite electrodes and the results of thermodynamic modeling Portland cement hydration. Boron was used as the additive. Boron acts as a catalyst and increases the yield of higher fullerenes C70 in plasma chemical synthesis. The carbon soot was used as a carbon nanomodifier. Carbon nanomodifier contains fullerenes C60 and C70. Thermodynamic calculations make it possible to evaluate the contribution of the carbon nanomodifier to the hydration process of Portland cement. Using thermodynamic calculations, changes in the phase composition and general properties of the system (complete enthalpy, entropy) were determined when introducing a carbon nanomodifier.