Mixture Of C60 Research Articles

Room temperature excitonic coupling in self-assembled copper – Fullerene hybrid films exposed to ambient air

Analytically sound combination of organic and inorganic semiconductors in designing functional hybrid nanomaterials promises new advances in nanoscience and in creation of next-generation optoelectronic devices. In this work, we report on combining two contrasting semiconductors (inorganic and organic) possessing attractive optical and electronic properties, namely Cu2O (in form of small single-crystalline nanoparticles, NPs) and C60-fullerene (as a medium supporting the NP ensemble), which were formed within the well-controlled Cux(Oy)C60 hybrid films through self-assembling and ambient air exposure of the vapour-deposited Cu and C60 mixture. The controllability of the hybrid film nanostructure was established and verified through systematic study of the films using Rutherford backscattering spectrometry, transmission electron microscopy, X-ray diffraction, Raman spectrometry and spectroscopic ellipsometry. The remarkable coincidence of the optical absorption peaks around 3.5 eV, reported for the Wannier-Mott (WM) excitons in a Cu2O crystal and detected for the Frenkel (F) excitons in the pristine C60 film, allowed us to observe room temperature polaritons as a product of the F-WM excitonic strong coupling. Quite high coupling energy of the FWM hybrid exciton estimated for the Cux(Oy)C60 films in the x interval of 5 < x < 15 (from 390 meV to 610 meV) implies the mediated effect of nanocavity photons and quantum confinement effect, strongly enhancing the hybrid exciton coupling energy. The implemented study discloses the self-assembled Cux(Oy)C60 hybrid films as promising material for application in optoelectronics and nonlinear optics.

Optimizing Concrete Grade for a Sustainable Structural Design in Saudi Arabia

Buildings and facilities undergo several stages: the product stage, the construction stage, the use stage, the end-of-life stage, and the recycling stage. The life cycle of any facility or building contributes to embodied carbon (EC) emissions. The product stage, also known as the cradle-to-gate stage (A1–A3), registers the highest emissions, estimated to account for 70% of the total environmental impact. The continuing population growth in Saudi Arabia necessitates urgent action to identify and implement solutions for reducing greenhouse gas emissions and mitigating environmental risks. This study investigates the optimal method to analyze the grade of concrete for specific structural elements (columns) in a particular work area, adhering to accurate and methodological standards outlined in the Saudi Building Code (SBC). The bill of quantities (BOQ) determined the amount of building materials for the structure considered in this study. Reliable embedded carbon coefficients (ECCs) for structural materials such as concrete and steel were determined following life cycle assessment principles. They were analyzed using the Inventory of Carbon and Energy (ICE; Version 2.0) and Global Warming Potential (GWP). The obtained values varied based on the components of each mixture. This study determined the cost of each concrete mixture and steel, selecting the optimal mixture based on both EC and material cost. Since the quantity of cement significantly affects EC emissions in a concrete mixture, it is essential to select appropriate plasticizers and concrete types. This study evaluated the C30, C40, C50, C60, and C70 mixtures. Among these, the C70 mixture demonstrated the best environmental impact and was the least expensive compared to the basic C40 mixture for the estimated quantities of concrete and steel. The estimated reductions in cost and environmental impact were 33% and 27%, respectively. This groundbreaking study paves the way for low-carbon structural design in large hotels across Saudi Arabia, offering valuable insights for future projects and contributing significantly to energy conservation.

Asymmetrical impurity effect of C70:C60 mixture in thick small molecule organic photovoltaic cells

Fullerenes, especially C70 and C60, and their derivatives are popular acceptor materials for many organic semiconductor devices, including organic photovoltaic cells. One of the main impurities in C70 is C60, and intentional mixture of C60 and C70, or their derivatives, which have been utilized for maximizing the performance of organic photovoltaic cells or perovskite solar cells. However, the influence of impurities in C70 on the device characteristics has not been fully clarified when incorporating C70 into organic devices. To further clarify the relationship between the fullerene mixture and impurities, the effect of impurities in fullerenes on thick photovoltaic cells was evaluated, and a strange asymmetrical impurity effect of the C60:C70 mixture was demonstrated by using C70 with various purities as an acceptor material and zinc phthalocyanine (ZnPc) as a donor material. It was found that C60, C78, and C84 impurities in C70 caused carrier recombination during electron transport, but the same effect of the C70 impurity in C60 was much smaller. Additionally, the impurity effect of higher fullerenes on C70 was clearly larger than that of C60. The effect of higher fullerene impurities can be explained by electron trapping due to their deep lowest unoccupied molecular orbital (LUMO) levels. For the small difference of LUMO energy between C70 and C60, however, it is suggested that the shallow trapping of C70 impurities does not largely inhibit the transport of photocarriers by C60, while the low energy barrier of C60 impurities largely inhibits the transport of photocarriers by C70. For clear comparison, the photoelectrical conversion layers were crystallized using co-evaporant induced crystallization. An effective purification method for C70 using sublimation purification, which depends on the C70 concentration in the sublimation source, is also reported.

Formation of a low-symmetry Pd8 molecular barrel employing a hetero donor tetradentate ligand, and its use in the binding and extraction of C70.

The majority of reported metallo-supramolecules are highly symmetric homoleptic assemblies of M x L y type, with a few reports on assemblies that are obtained using multicomponent self-assembly or using ambidentate ligands. Herein, we report the use of an unsymmetrical tetratopic ligand (Lun) containing pyridyl and imidazole donor sites in combination with a cis-protected Pd(ii) acceptor for the formation of a low-symmetry M8Lun 4 molecular barrel (UNMB). Four potential orientational isomeric (HHHH, HHHT, HHTT, and HTHT) molecular barrels can be anticipated for the M8Lun 4 type metallo-assemblies. However, the formation of an orientational isomer (HHTT) of the barrel was suggested from single-crystal X-ray diffraction and 1H NMR analysis of UNMB. Two large open apertures at terminals and the hydrophobic confined space surrounded by four aromatic panels of Lun make UNMB a potential host for bigger guests. UNMB encapsulates fullerenes C70 and C60 favoured by non-covalent interactions between the fullerenes and aromatic panels of the ligand molecules. Experimental and theoretical studies revealed that UNMB has the ability to bind C70 more strongly than its lower analogue C60. The stronger affinity of UNMB towards C70 was exploited to separate C70 from an equimolar mixture of C70 and C60. Moreover, C70 can be extracted from the C70⊂UNMB complex by toluene, and therefore, UNMB can be reused as a recyclable separating agent for C70 extraction.

Simultaneous Quantification of Fullerenes C60 and C70 in Organic Solvents by Excitation–Emission Matrix Fluorescence Spectroscopy

Excitation–emission matrix (EEM) fluorescence spectroscopy of unmodified (pristine) fullerenes C60 and C70 in benzene, toluene, and n-hexane at room temperature was used for their quantification by their solvent-dependent EEM bands specific to each fullerene. The intensity and parameters of fluorescence depend on both the fullerene and solvent and provide the conditions for the quantification of both fullerenes in their mixtures without separation. The detection limits for C60 in n-hexane and C70 in benzene under the selected conditions are 7 and 2 nmol/L, respectively. The approach was tested for model and real mixtures of fullerenes C60 and C70.

Quasi-liquid composites based on poly(ethylene terephthalate) films with fullerene and dichlorobenzene

Quasi-liquid composites based on poly(ethylene terephthalate) (PET) films with 9 wt% solution of the C60 (70%) and C70 (∼30%) fullerenes mixture in dichlorobenzene (DCB) have been obtained. It has been shown that PET swelling in the fullerene solution in DCB is accompanied by penetration of fullerene into the polymer structure, and PET films are deformed by the mechanism of intercrystallite crazing. As has been revealed by UV spectroscopy, fullerene incorporated into composite remains monomeric as in solution.

Dielectric and thermal performance of a C60-based nanofluid and a C60-loaded ferrofluid

Liquids in electrical devices often act as electrical insulators and cooling media. To enhance both dielectric and thermal properties of liquids, various nanoparticles can be dispersed in the liquids resulting in effective nanofluids. In this research, a new generation transformer oil prepared by a gas-to-liquid technology has been used to prepare a mono-nanofluid with fullerene C60 nanoparticles (0.01%w/V) and a hybrid nanofluid with C60 (0.01%w/V) and iron oxide nanoparticles (0.01%w/V), so-called C60-loaded ferrofluid. Both nanofluids and the oil were subjected to experimental investigation of frequency-dependent dielectric response, dielectric breakdown, and thermal conductivity at various temperatures. Finally, the three liquids were applied in a single-phase transformer, and temperature rise tests of the loaded transformer were conducted. The dielectric spectroscopy revealed three orders of magnitude higher dielectric losses in C60-loaded ferrofluid than in the oil and C60 nanofluid, where the losses are of conducting nature. In C60-loaded ferrofluid, an interfacial relaxation process is considered in addition. C60 particles in the oil increased its breakdown voltage by 17%, while the mixture of C60 and magnetic nanoparticles resulted in a 12.5% reduction of the breakdown voltage. The enhancement has been ascribed to the strong capacity of C60 to absorb electrons and their ability to weaken the photoionization in the head of the streamer. The thermal conductivity of both nanofluids decreases with temperature, and the effective medium theory can well predict it. A significant decrease in the transformer temperature rise up to 8 K has been found for C60 nanofluid, as compared with the temperature rise achieved with the transformer oil. The temperature rise was also reduced with C60-loaded ferrofluid (up to 5.6 K). The lower cooling efficiency of the hybrid nanofluid was attributed to the high dielectric losses generating undesirable heat with a counter-productive effect on the cooling process.

C–H⋯S Hydrogen Bond Assisted Supramolecular Encapsulation of Fullerenes with Nanobelts

C–H⋯S Hydrogen Bond Assisted Supramolecular Encapsulation of Fullerenes with Nanobelts

Multidimensional Mass Spectrometry Assisted Metallo-Supramolecular Chemistry

Multidimensional Mass Spectrometry Assisted Metallo-Supramolecular Chemistry

Generalizing the Chiral Self-Assembly of Spheres and Tetrahedra to Non-Spherical and Polydisperse Molecules in (C70)x(C60)1-x(SnI4)2.

We describe the spontaneous chiral self-assembly of C70 with SnI4 as well as a mixture of C60 and C70 with SnI4. Macroscopic single crystals with the formula (C70)x(C60)1-x(SnI4)2 (x = 0-1) are reported. C60, which is spherical, and C70, which is ellipsoidal, form a solid solution in these crystals, and the cubic lattice parameter of the chiral phase linearly increases as x grows from 0 to 1 in accordance with Vegard's law. Our results demonstrate that nonspherical particles and polydispersity are not an impediment to the growth of chiral crystals from high-symmetry achiral precursors, providing a route to assemble achiral particles including colloidal nanocrystals and engineered nanostructures into chiral materials without the need to use external templates or forces.

Tracing the Jahn‐Teller Distortion of C60n− in Isostructural Fullerides [M(NH3)7]C60 ⋅ NH3, M=Ba, Sr, K

AbstractSingle crystals of new [Sr(NH3)7]C60 ⋅ NH3 (compound 1) and [K(NH3)7]C60 ⋅ NH3 (compound 2) were prepared by extracting mixtures of potassium and C60 with liquid ammonia, where for the synthesis of 1 solid strontium chloride was added to the extraction mixture. The procedure applied relies on self‐contained continuous evaporation and condensation of ammonia at subcritical conditions in a special, sealed glass vessel, at room temperature (RT). According to single crystal structure analyses on data collected at 123 K, both, 1 and 2, are isostructural with [Ba(NH3)7]C60 ⋅ NH3 (compound 3). The structure determinations suffer either from systematic twinning (3), or positional disorder for 1 and 2. Crystals of 3, grown and handled throughout at low temperature (123 K), developed large enough twin domains such that an inversion twin type refinement in space group R3m converged properly. For 1 and 2, the crystals of which were grown at RT and subsequently cooled for data collection, refinements of the same structure model were only possible in R‐3m while applying split atom positions. For 1 and 3 the accuracy achieved was sufficient to extract a particular bonding distortion pattern for (C60)2−, which is lifting the degeneracy of the HOMO according to the Jahn‐Teller theorem. Independent quantum chemical calculations are lending convincing support to the experimental findings.

Effective Encapsulation of C60 by Metal–Organic Frameworks with Polyamide Macrocyclic Linkers

AbstractA flexible benzylic amide macrocycle, functionalized with two carboxylic acid groups, was employed as the organic ligand for the preparation of robust copper(II)‐ and zinc(II)‐based metal–organic frameworks. These polymers crystallized in the C2/m space group of the monoclinic crystal system, creating non‐interpenetrated channels in one direction with an extraordinary solvent‐accessible volume of 46 %. Unlike metal–organic rotaxane frameworks having benzylic amide macrocycles as linkers, the absence of the thread in these novel reticular materials causes a decrease of dimensionality and an improvement of pore size and dynamic guest adaptability. We studied the incorporation of fullerene C60 inside the adjustable pocket generated between two macrocycles connected to the same dinuclear clusters, occupying a remarkable 98 % of the cavities inside the network. The use of these materials as hosts for the selective recognition of different fullerenes was evaluated, mainly encapsulating the smaller size fullerene derivative in several mixtures of C60 and C70.

Glassy Porphyrin/C60 Composites: Morphological Engineering of C60 Fullerene with Liquefied Porphyrins.

Morphological control of C60 fullerene using liquefied porphyrins (1 and 2) as the host matrices was explored. Slow evaporation of the solvent of the equimolar mixture of porphyrin and C60 in toluene afforded the porphyrin/C60 composite with a 3:1 molar ratio. The stoichiometric binding behaviors suggest that specific porphyrin-C60 interactions operate the formation of the porphyrin/C60 composites, as corroborated by spectroscopic and thermal properties, and glazing-incidence wide-angle X-ray diffraction. Under the bulk conditions, the conventional thermodynamic advantage of multiple binding cooperativity for molecular recognition is unlikely to explain the stoichiometric binding behaviors. Instead, we propose a size-matching effect on the porphyrin-C60 interaction in the bulk porphyrin matrices, i.e., "supramolecular solvation". The glassy nature of the porphyrin matrices was transmitted to C60 through the specific interaction, and the porphyrin/C60 composites adopted glassy states at room temperature.

A Macrocycle Based on a Heptagon-Containing Hexa-peri-hexabenzocoronene.

A cyclophane is reported incorporating two units of a heptagon-containing extended polycyclic aromatic hydrocarbon (PAH) analogue of the hexa-peri-hexabenzocoronene (HBC) moiety (hept-HBC). This cyclophane represents a new class of macrocyclic structures that incorporate for the first time seven-membered rings within extended PAH frameworks. The saddle curvature of the hept-HBC macrocycle units induced by the presence of the nonhexagonal ring along with the flexible alkyl linkers generate a cavity with shape complementarity and appropriate size to enable π interactions with fullerenes. Therefore, the cyclophane forms host-guest complexes with C60 and C70 with estimated binding constants of Ka =420±2 m-1 and Ka =(6.49±0.23)×103 m-1 , respectively. As a result, the macrocycle can selectively bind C70 in the presence of an excess of a mixture of C60 and C70 .

A Macrocycle Based on a Heptagon‐Containing Hexa‐peri‐hexabenzocoronene

AbstractA cyclophane is reported incorporating two units of a heptagon‐containing extended polycyclic aromatic hydrocarbon (PAH) analogue of the hexa‐peri‐hexabenzocoronene (HBC) moiety (hept‐HBC). This cyclophane represents a new class of macrocyclic structures that incorporate for the first time seven‐membered rings within extended PAH frameworks. The saddle curvature of the hept‐HBC macrocycle units induced by the presence of the nonhexagonal ring along with the flexible alkyl linkers generate a cavity with shape complementarity and appropriate size to enable π interactions with fullerenes. Therefore, the cyclophane forms host–guest complexes with C60 and C70 with estimated binding constants of Ka=420±2 m−1 and Ka=(6.49±0.23)×103 m−1, respectively. As a result, the macrocycle can selectively bind C70 in the presence of an excess of a mixture of C60 and C70.

Effect of switching ultrasonic amplitude in preparing a hybrid of fullerene (C60) and gallium oxide (Ga2O3)

In this study, we proposed 'switching ultrasonic amplitude' as a new strategy of applying ultrasonic energy to prepare a hybrid of buckminsterfullerene (C60) and gallium oxide (Ga2O3), C60/Ga2O3. In the proposed method, we switched the ultrasonic amplitude from 25% to 50% (by 5% amplitude per 10min, within 1h of ultrasonic irradiation) for the sonochemical treatment of a heterogeneous aqueous mixture of C60 and Ga2O3 by a probe-type ultrasonic horn operating at 20kHz. We found that compared to the conventional techniques associated with high amplitude oriented ultrasonic preparation of functional materials, switching ultrasonic amplitude can better perform in preparing C60/Ga2O3 with respect to avoiding titanium (Ti) as an impurity generating from the tip erosion of a probe-type ultrasonic horn during high amplitude ultrasonic irradiation in an aqueous medium. Based on SEM/EDX analysis, the quantity of Ti (wt.%) in C60/Ga2O3 prepared by the proposed technique of switching ultrasonic amplitude was found to be 1.7% less than that prepared at 50% amplitude of ultrasonic irradiation. The particles of C60/Ga2O3 prepared by different modes of amplitude formed large (2-12μm) aggregates in their solid phase.Whereas, in the aqueous medium, they were found to disperse in their nano sizes. The minimum particle size of the as-synthesized C60/Ga2O3 in an aqueous medium prepared by the proposed method of switching ultrasonic amplitude reached to approximately 467nm. Comparatively, the minimum particle sizes were approximately 658nm and 144nm, using 25% and 50% amplitude, respectively. Additionally, Ga2O3 went under hydration during ultrasonic irradiation. Moreover, due to the electron cloud interference from C60 in the hybrid structure of C60/Ga2O3, the vibrational modes of Ga2O3 were Raman inactive in C60/Ga2O3.

Technology of producing nanomaterals and their use

This work is devoted to the technology for producing nanomaterials, in particular, the method of arc synthesis in helium medium under certain optimal conditions with a maximum yield of material, as well as their practical application as additives, which improve anti-corrosion properties. In this work, we used the extraction of fullerenes using the Soxhlet apparatus, which is designed to evaporate toluene from fullerene-containing sludge. Carbon nanostructures of a mixture of fullerenes C60 and C70 were obtained at a current of ~ 200 A, studied using Raman spectroscopy and optical microscopy at the National Nanotechnology laboratory at KazNU named after al-Farabi.

Characterization and Cytotoxicity of Polyprenol Lipid and Vitamin E-TPGS Hybrid Nanoparticles for Betulinic Acid and Low-Substituted Hydroxyl Fullerenol in MHCC97H and L02 Cells.

BackgroundThis study demonstrated an innovative formulation including the polyprenol (GBP) lipid and vitamin E-TPGS hybrid nanoparticles (NPs) which was aimed to control the transfer of betulinic acid (BA) and low-substituted hydroxyl fullerenol (C60(OH)n). Additionally, it developed BA-C60(OH)n-GBP-TPGS-NPs delivery system and researched the anti-hepatocellular carcinoma (HCC) effects.Materials and MethodsThe NPs were prepared by nanoprecipitation with ultrasonic-assisted emulsification (UAE) method. It was characterized by scanning electronic microscopy (SEM), transmission electron microscopy (TEM), FTIR spectrum, size distribution and zeta potential. Physical and chemical properties were evaluated through measurement of drug release, stability studies, drug loading efficiency (DE) and encapsulation efficiency (EE). Biological activities were evaluated through measurement of MTT assay, lactate dehydrogenase leakage assay (LDH), cell proliferation assays, cell apoptosis analysis, comet assay, wound healing assay, cell invasion and Western blot analysis.Results and ConclusionsThe NPs exhibited clear distribution characteristics, improved solubility and stability. BA and C60(OH)n for the NPs displayed a biphasic release pattern with sustained drug release properties. The mixture of C60(OH)n with different hydroxyl groups may have a certain effect on the stability of the NPs system itself. The NPs could effectively inhibit MHCC97H cell proliferation, migration and invasion in vitro. Combined use of C60(OH)n and BA in GBP lipids may improve the inhibit effect of C60(OH)n or BA against HCC cells and reduce cytotoxicity and genotoxicity of C60(OH)n for normal cells. We concluded that one of the important mechanisms of BA-C60(OH)n-GBP-TPGS-NPs inhibiting MHCC97H cells is achieved by up-regulating the expression of Caspase-3, Caspase-8 and Caspase-9.

Thin Films Based on Cobalt Phthalocyanine:C60 Fullerene:ZnO Hybrid Nanocomposite Obtained by Laser Evaporation.

Matrix-assisted pulsed laser evaporation (MAPLE) was used to deposit hybrid nanocomposite thin films based on cobalt phthalocyanine (CoPc), C60 fullerene and ZnO nanoparticles. The inorganic nanoparticles, with a size of about 20 nm, having the structural and optical properties characteristic of ZnO, were chemically synthesized by a simple precipitation method. Furthermore, ZnO nanoparticles were dispersed in a dimethyl sulfoxide solution in which CoPc and C60 had been dissolved, ready for the freezing MAPLE target. The effect of the concentration of ZnO nanoparticles on the structural, morphological, optical and electrical properties of the CoPc:C60:ZnO hybrid nanocomposite layers deposited by MAPLE was evaluated. The infrared spectra of the hybrid nanocomposite films confirm that the CoPc and C60 preserve their chemical structure during the laser deposition process. The CoPc optical signature is recognized in the ultraviolet–visible (UV–Vis) spectra of the obtained layers, these being dominated by the absorption bands associated to this organic compound while the ZnO optical fingerprint is identified in the photoluminescence spectra of the prepared layers, these disclosing the emission bands linked to this inorganic semiconductor. The hybrid nanocomposite layers exhibit globular morphology, which is typical for the thin films deposited by MAPLE. Current-voltage (J-V) characteristics of the structures developed on CoPc:C60:ZnO layers reveal that the addition of an appropriate amount of ZnO nanoparticles in the CoPc:C60 mixture leads to a more efficient charge transfer between the organic and inorganic components. Due to their photovoltaic effect, structures featuring such hybrid nanocomposite thin films deposited by MAPLE can have potential applications in the field of photovoltaic devices.

Manipulating the Structural Transformation of Fullerene Microtubes to Fullerene Microhorns Having Microscopic Recognition Properties.

We report the production of fullerene microtubes (FMTs), having solid cores bisecting their tubular cavities, from solutions of mixtures of fullerene C60 and C70 and have demonstrated the structural transformation of FMTs to fullerene microhorns (FMHs) upon their exposure to alcohol/mesitylene mixtures at 25 °C. The conically shaped microhorns have hollow interiors and exhibit preferential recognition of silica particles over fullerene C70, polystyrene (PS) latex, PS hydroxylate, or PS carboxylate particles of similar dimensions due to strong electrostatic interactions between negatively charged FMHs and positively charged silica particles.