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The rapid development of non-fullerene acceptors (NFAs) with strong near-infrared absorption has led to remarkably enhanced short-circuit current density (Jsc) values in organic solar cells (OSCs). NFAs based on the benzotriazole (Bz) fused-ring π-core have great potential in delivering both high Jsc and decent open-circuit voltage values due to their strong intramolecular charge transfer with reasonably low energy loss. In this work, we have designed and synthesized a series of Bz-based NFAs, PN6SBO-4F, AN6SBO-4F and EHN6SEH-4F, via regiospecific N-alkyl engineering based on the high-performance NFA mBzS-4F that was reported previously. The molecular packing of mBzS-4F, AN6SBO-4F, and EHN6SEH-4F single crystals was analyzed using X-ray crystallography in order to provide a comprehensive understanding of the correlation between the molecular structure, the charge-transporting properties, and the solar cell performance. Compared with the typical honeycomb single-crystal structure of Y6 derivatives, these NFAs exhibit distinctly different molecular packing patterns. The strong interactions of terminal indanone groups in mBzS-4F and the J-aggregate-like packing in EHN6SEH-4F lead to the formation of ordered 3D networks in single-crystals with channels for efficient charge transport. Consequently, OSCs based on mBzS-4F and EHN6SEH-4F show efficient photon-to-current conversions, achieving the highest power conversion efficiency of 17.48% with a Jsc of 28.83 mA cm−2.

Graphene oxide/reduced Graphene oxide based hybrid nano composites have been a hot topic of research in the past few decades. Their Remarkable optical, electrical, mechanical and thermal properties brought them fore front among other 2-D materials. Graphene is a single 2-D sheet of graphite. So it is known to be mother of other carbon materials like carbon nanotube, fullerene, and their derivatives graphene oxide (GO), reduced Graphene Oxide (rGO). Graphene derivatives (GO, rGO) and their hybrids with metals (M) and Metal Oxides (MO) have proven to be an effective materials for sensors, solar cells, water purification and so on. This review article comprises the low cost synthesis techniques most commonly used to produce these graphene derivatives, discuss how synthesis affects their key material properties and highlight some examples of hybrid metal/metal oxide Nano composites with unique and impressive properties and its applications. Specifically, this review highlights their performance in spectroscopy based optical sensors, energy storage and water purifications. Finally, this review discusses the outlook and remaining challenges in the field of practical industrial-scale production.

The morphology development of polymer-based blends, such as those used in organic photovoltaic (OPV) systems, typically arrests in a state away from equilibrium-how far from equilibrium this is will depend on the materials chemistry and the selected assembly parameters/environment. As a consequence, small changes during the blend assembly alter the solid-structure development from solution and, in turn, the final device performance. Comparing an open-cage ketolactam fullerene with the prototypical[6,6]-phenyl-C61-butyric acid methyl ester in blends with poly[2,5-bis(3-hexadecylthiophen-2-yl)thieno[3,2-b]thiophene] (PBTTT), we demonstrate that experimentally established, non-equilibrium temperature/composition phase diagrams can be useful beyond rationalization of optimum blend composition for OPV device performance. Indeed, they can be exploited as tools for rapid, qualitative structure-property mapping, providing insights into why apparent similar donor:acceptor blends display different optoelectronic processes resulting from changes in the phase-morphology formation induced by the different chemistries of the fullerenes.

To explore the effect of different positions and number of pyrrolidine bound to the carbon cage on the stabilization effect of fulleropyrrolidine derivatives to nitrocellulose (NC)/nitroglycerine (NG), we synthesized N-(4-methoxy) phenylpyrrolidine-C60 and four different of bis(N-(4-methoxy) phenylpyrrolidine)-C60 compounds through Prato reaction. Their structures were characterized by UV–vis, 1H NMR, 13C NMR, high-resolution mass spectroscopy, and single-crystal X-ray diffraction. Their stabilization effect to NC/NG were investigated using differential scanning calorimetry, methyl violet, vacuum stabilization effect, weight loss, and accelerating rate calorimeter tests. The results indicated these compounds had excellent stabilization effect to NC/NG. The stabilization effect of the fulleropyrrolidine bisadducts to NC/NG is significantly better than that of fulleropyrrolidine monoadduct and C60. Moreover, the position where pyrrolidine binds to fullerene in fulleropyrrolidine bisadducts is different, and its stabilization effect to NC is also different. The stabilization effect order of different bisadduct isomers to nitrocellulose is as follows: e-edge > trans-2> cis-2> trans-3. Electron paramagnetic resonance (EPR) and FT-IR were used to study the stabilization mechanism of fulleropyrrolidine derivatives to NC/NG. The EPR results also show that fulleropyrrolidine bisadducts with different addition sites have different abilities to absorb nitroxide, and their ability is better than that of the monoadduct and C60, which is consistent with the results of stabilization effect performance test.

At the temperature 293 K, the influence of two types of nanoimpurities (carbon multiwall nanotubes and C60 fullerene) both separately and together on the dielectric properties of Shell oil transformer oil has been studied. It has been shown that these impurities do not significantly effect on the value of the dielectric permittivity of Shell oil, but more significantly increase its conductivity. It has been found that in the presence of nanotubes inside Shell oil, the dependence of its electrical conductivity on the fullerene concentration is nonmonotonic. The samples with the fullerene concentration 100 ppm have the highest conductivity. At the fullerene concentration 300 ppm, the conductivity of Shell oil with the impurities of carbon nanotube and C60 fullerene becomes almost equal to the electrical conductivity of Shell oil only with the impurities of carbon nanotubes. It has been suggested that C60 fullerene can be used to reduce the electrical conductivity of Shell oil with magnetic nanoparticles required to increase the cooling efficiency of transformers under the action of their own magnetic field.

Strained aromatic macrocycles based on cycloparaphenylenes (CPPs) are the shortest repeating units of armchair single-walled carbon nanotubes. Since the development of several new synthetic methodologies for accessing these structures, their properties have been extensively studied. Besides the fundamental interest in these novel molecular scaffolds, their application in the field of materials science is an ongoing topic of research. Most of the reported CPP-type macrocycles display strong binding toward fullerenes, due to the perfect match between the convex and concave π-surfaces of fullerenes and CPPs, respectively. Highly functionalized CPP derivatives capable of supramolecular binding with other molecules are rarely reported. The synthesis of highly functionalized [n]cyclo-2,7-pyrenylenes leads to CPP-type macrocycles with a defined cavity capable of binding non-fullerene guests with high association constants.

Non-fullerene based organic compounds are considered promising materials for the fabrication of modern photovoltaic materials. Non-fullerene-based organic solar cells comprise of good photochemical and thermal stability along with longer device lifetimes as compared to fullerene-based compounds. Five new non-fullerene donor molecules were designed keeping in view the excellent donor properties of 3-bis(4-(2-ethylhexyl)-thiophen-2-yl)-5,7-bis(2ethylhexyl) benzo[1,2-:4,5-c′]-dithiophene-4,8-dione thiophene-alkoxy benzene-thiophene indenedione (BDD-IN) by end-capped modifications. Photovoltaic and electronic characteristics of studied molecules were determined by employing density functional theory (DFT) and time dependent density functional theory (TD-DFT). Subsequently, obtained results were compared with the reference molecule BDD-IN. The designed molecules presented lower energy difference (ΔΕ) in the range of 2.17–2.39 eV in comparison to BDD-IN (= 2.72 eV). Moreover, insight from the frontier molecular orbital (FMO) analysis disclosed that central acceptors are responsible for the charge transformation. The designed molecules were found with higher λmax values and lower transition energies than BDD-IN molecule due to stronger end-capped acceptors. Open circuit voltage (Voc) was observed in the higher range (1.54–1.78 V) in accordance with HOMOdonor–LUMOPC61BM by designed compounds when compared with BDD-IN (1.28 V). Similarly, lower reorganization energy values were exhibited by the designed compounds in the range of λe(0.00285–0.00370 Eh) and λh(0.00847–0.00802 Eh) than BDD-IN [λe(0.00700 Eh) and λh(0.00889 Eh)]. These measurements show that the designed compounds are promising candidates for incorporation into solar cell devices, which would benefit from better hole and electron mobility.

We present a semi-anisotropic interfacial potential (SAIP) designed to classically describe the interaction between gold and two-dimensional (2D) carbon allotropes such as graphene, fullerenes, or hydrocarbon molecules. The potential is able to accurately reproduce dispersion-corrected density functional theory (DFT+D3) calculations performed over selected configurations: a flat graphene sheet, a benzene molecule, and a C60 fullerene, physisorbed on the Au(111) surface. The effects of bending and hydrogen passivation on the potential terms are discussed. The presented SAIP provides a noticeable improvement in the state-of-the-art description of Au–C interfaces. Furthermore, its functional form is suitable to describe the interfacial interaction between other 2D and bulk materials.

The distinction of different organic materials in phase mixtures is hampered in electron microscopy because electron scattering does not strongly differ in carbon-based materials that mainly consist of light elements. A successful strategy for contrast enhancement is selective staining where one phase of a material mixture is labeled by heavier elements, but suitable staining agents are not available for all organic materials. This is also the case for bulk-heterojunction (BHJ) absorber layers of organic solar cells, which consist of interpenetrating networks of donor and acceptor domains. The domain structure strongly influences the power conversion efficiency, and nanomorphology optimization often requires real-space information on the sizes and interconnectivity of domains with nanometer resolution. In this work, we have developed an efficient approach to selectively stain sulfur-containing polymers by homogeneous Cu infiltration, which generates strong material contrast in scanning (transmission) electron microscopy (S(T)EM) images of polymer:fullerene BHJ layers. Cross-section lamellae of BHJ layers are prepared for STEM by focused-ion-beam milling and are attached to a Cu lift-out grid as a copper source. After thermal treatment at 200 °C for 3 h in air, sulfur-containing polymers are homogeneously infiltrated by Cu, while the fullerenes are not affected. Selective Cu staining is applied to map the phase distribution in PTB7:PC71BM BHJ layers fabricated with different processing additives to tailor the nanomorphology. The strong contrast between polymer and fullerene domains is the prerequisite for the three-dimensional reconstruction of the domain structure by focused-ion-beam/scanning-electron-microscopy tomography.

This work demonstrates a simple yet effective method to significantly improve the power conversion efficiency (PCE) of highly efficient non-fullerene organic solar cells by mixing two electron transport materials. The new electron transport layer shows an energy level better aligned with the active layer and an improved morphology that could reduce the active layer-electrode contact. These improvements lead to enhanced charge extraction, better charge selectivity, suppressed exciton recombination, and finally a boosted PCE in the PM6:Y6-based solar cells. When applied in conjunction with the non-halogenated solvent-processed PM6:PY-IT-based active layer, the mixed ETL also gives rise to a leading result for binary all-polymer solar cells (PCE of >16%) with a concurrent increase in VOC, JSC, and FF.

Surface cracks could improve the optical and photoelectronic properties of crystalline materials as they increase specific surface area, but the controlled self-assembly of fullerene (C60 ) molecules into micro-/nanostructures with surface cracks is still challenging. Herein, we report the morphology engineering of novel C60 microstructures bearing surface cracks for the first time, selecting phenetole and propan-1-ol (NPA) as good and poor solvents, respectively. Our systematic investigations reveal that phenetole molecules initially participate in the formation of the ends of the C60 microstructures, and then NPA molecules are involved in the gradual growth of the sidewalls of the microstructures. Therefore, the surface cracks of C60 microstructures can be finely regulated by adjusting the addition of NPA and the crystallization time. Interestingly, the cracked C60 microstructures show superior photoluminescence properties relative to the smooth microstructures due to the increased specific surface area. In addition, C60 microstructures with wide cracks show preferential recognition of silica particles over C60 particles owing to electrostatic interactions between the negatively charged C60 microstructures and the positively charged silica microparticles. These C60 crystals with surface cracks have potential applications from optoelectronics to biology.

Development of theoretical tools to analyze electronic structure of complex nanomaterials depending on features of spatial and chemical organizations of different phases is of interest from both practical and theoretical points of view. Therefore, in this work, an approach based on computations of the atomic charge distribution functions (CDF) in parallel to calculations of the distribution functions of the chemical shifts (SDF) of protons is developed to be applied to a set of complex oxide and carbon nanomaterials. Binary nanooxides (alumina/silica, titania/silica), 3d-metal-doped anatase, activated carbon, carbon nanotube, fullerene C60, graphene oxide, and N-doped Kagome graphene are considered here as representatives of different classes of nanomaterials. The analyses of the CDF and SDF as nonlocal characteristics of certain kinds of atoms in complex systems provide a deeper insight into electronic structure features depending on composition of the materials, guest phase-doped host phase at various amounts of dopants, structure of O- and OH-containing surface sites, amounts and organization of adsorbed water, formation of neutral and charged surface functionalities, bonding of solvated ions, etc. The CDF of metal and hydrogen atoms (electron-donors) are more sensitive to the mentioned factors than the CDF of O, N, and C atoms (electron acceptors) in various systems. As a whole, the use of the CDF and SDF in parallel expands the tool possibility in detailed analysis of the structural and interfacial effects in dried and wetted complex nanomaterials.

We report a comprehensive study of a novel isomer of C70(CF3)12, p9mp-C70(CF3)12, whose electrochemical behavior differs from most of the other trifluoromethylated fullerenes. The addition pattern of p9mp-C70(CF3)12 is established by means of 19F-19F COSY NMR spectroscopy and DFT calculations. Like p7mp-C70(CF3)10, the new isomer p9mp-C70(CF3)12 undergoes dimerization to the [C70(CF3)12]22- upon single-electron reduction. The electrochemical observations are supported by the DFT calculations of dimerization energy and the temperature dependence of the CW X-band EPR spectroscopy data. Experimentally determined dimerization energies of p9mp-C70(CF3)12-• and p7mp-C70(CF3)10-• in solution are ca -8 and -26 kJ mol-1, respectively, in good correspondence with DFT data.

Molecular surgery provides the opportunity to study relatively large molecules encapsulated within a fullerene cage. Here we determine the location of an H2O molecule isolated within an adsorbed buckminsterfullerene cage, and compare this to the intrafullerene position of HF. Using normal incidence X-ray standing wave (NIXSW) analysis, coupled with density functional theory and molecular dynamics simulations, we show that both H2O and HF are located at an off-centre position within the fullerene cage, caused by substantial intra-cage electrostatic fields generated by surface adsorption of the fullerene. The atomistic and electronic structure simulations also reveal significant internal rotational motion consistent with the NIXSW data. Despite this substantial intra-cage interaction, we find that neither HF or H2O contribute to the endofullerene frontier orbitals, confirming the chemical isolation of the encapsulated molecules. We also show that our experimental NIXSW measurements and theoretical data are best described by a mixed adsorption site model. The chemical nature of molecules encapsulated within fullerenes remain debated, with reports proposing a Faraday cage effect. Here, the authors show that H2O and HF molecules encapsulated inside a C60 cage experience a substantial intra-cage electrostatic interaction that results in off-center locations; despite this, the endofullerene’s frontier orbitals is unaffected, resulting in chemical shielding of the caged molecule.

In this work, a semi-transparent, low-cost and easy processable graphene derivative and PH1000 (conductive PEDOT:PSS polymer) based bilayer anode, is presented as a sustainable potential alternative to ITO. The simple mechanical-synthesized graphene derivative was in aqueous-suspension processed (SPG) and drop-coated onto a common glass substrates. The SPG film presents a Raman intensity ratio ( I D / I G ) of 0.56 and a number of 7 sheets theoretically estimated. Modified PH1000 with dimethyl sulfoxide (DMSO) was spin-coated onto SPG layer. The bilayer anode (SPG/PH1000) exhibits a transmittance, roughness and resistance of 82 % (550 nm), 9 nm and 226 Ω / sq , respectively. The bilayer alternative electrode is used in the manufacture of organic solar cells (OSCs) based on the non-fullerene PBDB-T:ITIC active layer. Average power conversion efficiency (PCE) of 8.3 % (best 8.6 % ) is attained for control devices (using ITO as anode) and 4.0 % (best 4.2 % ) for devices with the alternative SPG/PH1000 bilayer anode. For OSCs fabrication, a vacuum free deposited top electrode Field’s metal (FM, an eutectic alloy of Bi 32.5 % , In 51 % and Sn 16.5 % , with a melting point above 62 ° C ) was used.

Methano[60]fullerenes with two and four nitroxide radicals are studied by EPR spectroscopy. It is shown that nitroxide derivatives of fullerene C60 undergo conformational changes in liquid solution. It is established that transitions between the two conformations take place in the case of the biradical adduct of C60 fullerene. For the tetraradical adduct in the trans-3 position, it is shown that the biradicals do not interact and behave independently; therefore, the two-conformational model provides a good description of the experimental data. A more complicated situation is implemented for the tetraradical adduct in the equatorial position. The biradicals are not independent for this system, and their interaction leads to an increase in the number of possible conformations. Thermodynamic parameters for these systems are calculated.

Recent studies have reported that adding nanoparticles to graphene enables macroscale superlubricity to be achieved. This study focuses on the role of nanoparticles in achieving superlubricity. First, because graphene nanoscrolls can be formed with nanoparticles as seeds under shear force, the applied load (or shear force) is adjusted to manipulate the formation of graphene nanoscrolls and to reveal the relationship between graphene-nanoscroll formation and superlubricating performance. Second, the load-carrying role of spherical nano-SiO2 particles during the friction process is verified by comparison with an elaborately designed fullerene that possesses a hollow-structured graphene nanoscroll. Results indicate that the incorporated nano-SiO2 particles have two roles in promoting the formation of graphene nanoscrolls and exhibiting load-carrying capacity to support macroscale forces for achieving macroscale superlubricity. Finally, macroscale superlubricity (friction coefficient: 0.006–0.008) can be achieved under a properly tuned applied load (2.0 N) using a simple material system in which a graphene/nano-SiO2 particle composite coating slides against a steel counterpart ball without a decorated diamond-like carbon film. The approach described in this study could be of significance in engineering.

Carbon nanomaterials such as fullerenes (C60) and graphene oxide (GO) are considered as promising candidates for diverse applications in biotechnology and biomedicine. However, their potential toxic effects are still under debate. Herein, by using melittin (Mel), a representative pore-forming peptide, as a testing molecule we demonstrated that even the low-concentrated (usually assumed non-toxic) C60 and GO could still mechanically perturb a cell membrane by adsorption and insertion, and consequently influence the function realization of membrane active proteins/peptides. Such perturbations, however, are particle-property and membrane-environment dependent. GO would sensitize both model bilayers and bacterial membranes to Mel, demonstrated as significantly enhanced membrane permeabilization ability or improved antibacterial performance of Mel. In contrast, C60 activates the permeabilization effect of Mel on model membranes, while produces exactly the reverse effect on living bacteria and mammalian cells. Simulations further provide molecular details of the structural disturbance and probe the residue-specific formation of C60-Mel complex in membrane. This work emphasizes the dependence of biological toxicity of nanomaterials on their physico-chemical properties, provides a facile method to detect the subtle structural perturbation of cell membranes at nanoscale, and suggests a necessity for a careful evaluation of the potential influences of nanomaterials on biological processes.

Geometries of molecule-molecule interfaces strongly influence the current passing from one molecule to another. The contact conductance of molecule-molecule junctions which consist of fullerene and tin phthalocyanine molecules is investigated with a low-temperature scanning tunneling microscope. Two types of molecules are deposited onto Cu(111). Fullerene molecules are transferred to tips through controlled contact of STM tips on molecules. The molecule-molecule junctions are formed by approaching fullerene-terminated tips to tin phthalocyanine molecules on Cu(111). Our experimental method can be extended to study the intermolecular charge transport of a range of molecular junctions.

The paper presents the results of an EPR study of a new organic photovoltaic composite with a nonfullerene acceptor PBDB-T : IT-M. The parameters of the EPR spectra of all photogenerated spin charge carriers, both trapped and mobile, have been determined, which are in good agreement with previously reported data. The dependences of the spin concentration of all trapped and mobile charge carriers on the photon energy demonstrate an extreme increase in the region of 2.37 eV, which coincides with the band gap of the PBDB-T : IT-M polymer composite. The introduction of 2,5-diphenyloxazole (PPO) as a photoactivator into the system of trace additives improves the composite morphology as a result of more intense π–π interaction between the components, which enhances the exchange interaction between them and stabilizes the amount of spin charge carriers, mainly localized in the energy traps of the polymer matrix. The exchange interaction between polymers and diphenyloxazole in the composite leads to a twofold increase in the number of spins in the energy region close to the band gap of the composite.

Quantum-mechanical models for the formation of metal–carbon complexes of Co, Ni, Cu, and Zn ions with С60 fullerene molecules and single-wall С48 carbon nanotubes (SWCNTs) are proposed. The results of calculations show that, in aqueous solutions of electrolytes, Co, Ni, Cu, and Zn ions can be adsorbed into the С60 fullerene and С48 SWCNT surfaces with the formation of stable carbon-nanomaterial—metal (CNM—M) complexes; in this case, the minimum energy of the С60–М complex for Co and Cu ions corresponds to the position above the С6 cell center; for a Ni ion, above the single С–С bond in the С6 cell; and for a Zn ion, above the C atom. The optimized states of the С48–М complexes correspond to the position of metal ions above the С6 cell center.

In this paper, we review recent research developments regarding the tribological performances of a series of inorganic nano-additives in lubricating fluids. First, we examine several basic types of inorganic nanomaterials, including metallic nanoparticles, metal oxides, carbon nanomaterials, and “other” nanomaterials. More specifically, the metallic nanoparticles we examine include silver, copper, nickel, molybdenum, and tungsten nanoparticles; the metal oxides include CuO, ZnO, Fe3O4, TiO2, ZrO2, Al2O3, and several double-metal oxides; the carbon nanomaterials include fullerene, carbon quantum dots, carbon nanotubes, graphene, graphene oxides, graphite, and diamond; and the “other” nanomaterials include metal sulfides, rare-earth compounds, layered double hydroxides, clay minerals, hexagonal boron nitride, black phosphorus, and nanocomposites. Second, we summarize the lubrication mechanisms of these nano-additives and identify the factors affecting their tribological performance. Finally, we briefly discuss the challenges faced by inorganic nanoparticles in lubrication applications and discuss future research directions. This review offers new perspectives to improve our understanding of inorganic nano-additives in tribology, as well as several new approaches to expand their practical applications.

Fullerene C60 and its derivatives are widely used in molecular electronics, photovoltaics, and battery materials, because of their exceptional suitability as electron acceptors. In this context, single-electron transfer on C60 generates the C60• - radical anion. However, the short lifetime of free C60• - hampers its investigation and application. In this work, we dramatically stabilize the usually short-lived C60• - species within a self-assembled M2L4 coordination cage consisting of a triptycene-based ligand and Pd(II) cations. The electron-deficient cage strongly binds C60 by providing a curved inner π-surface complementary to the fullerene's globular shape. Cyclic voltammetry revealed a positive potential shift for the first reduction of encapsulated C60, which is indicative of a strong interaction between confined C60• - and the cationic cage. Photochemical one-electron reduction with 1-benzyl-1,4-dihydronicotinamide allows selective and quantitative conversion of the confined C60 molecule in millimolar acetonitrile solution at room temperature. Radical generation was confirmed by nuclear magnetic resonance, electron paramagnetic resonance, ultraviolet-visible-near-infrared spectroscopy and electrospray ionization mass spectrometry. The lifetime of C60• - within the cage was determined to be so large that it could still be detected after one month under an inert atmosphere.

International audience; Nanostructuration of solar cells is an interesting approach to improve the photovoltaic conversion efficiency (PCE). This work aims at developing architectured 3D hybrid photovoltaic solar cells using ZnO nanowires (ZnONWs) as the electron transport layer (ETL) and nanocollectors of electrons within the active layer (AL). ZnONWs have been synthesized using a hydrothermal process with a meticulous control of the morphology. The AL of solar cells is elaborated using ZnONWs interpenetrated with a bulk heterojunction composed of donor (π-conjugate low band gap polymer: PBDD4T-2F)/acceptor (fullerene derivate: PC71BM) materials. An ideal interpenetrating ZnONW-D/A system with predefined specific morphological characteristics (length, diameter, and inter-ZnONW distances) was designed and successfully realized. The 3D architectures based on dense ZnONW arrays covered with conformal coatings of AL result in an increased amount of the ETL/AL interface, enhanced light absorption, and improved charge collection efficiency. For AL/ZnONW assembly, spin-coating at 100 °C was found to be the best. Other parameters were also optimized such as the D/A ratio and the pre/post-treatments achieving the optimal device with a D/A ratio of 1.25/1 and methanol treated on ZnONWs before and after the deposition of AL. A PCE of 7.7% (1.4 times better than that of the 2D cells) is achieved. The improvement of the performances with the 3D architecture results from both of: (i) the enhancement of the ZnO/AL surface interface (1 μm2/μm2 for the 2D structure to 6.6 μm2/μm2 for the 3D architecture), (ii) the presence of ZnONWs inside the AL, which behave as numerous nanocollectors (∼60 ZnONW/μm2) of electrons in the depth of the AL. This result validates the efficiency of the concept of nanotexturing of substrates, the method of solar cell assembly based on the nano-textured surface, the chosen morphological characteristics of the nanotexture, and the selected photoactive organic materials.

In recent years, various drug carrier nanomaterials have been investigated to improve drug delivery systems in cancer treatment. However, an ongoing requirement exists for more beneficial therapeutic materials, yielding rapid clearance, high capacity for reducing systemic toxicity via specific-tumor targeting, and superior drug solubility. Given that, carbon allotropes, including Active Carbon (AC), carbon nanotubes (CNTs), graphene and graphene oxides (GOs), nanodiamonds (NDs), fullerenes, carbon nanohorns, soporous carbons, and carbon dots, have been studied owing to their high thermal conductivity, rigid structure, flexibility for modification and functionalization, adequate surface-to-volume ratio, and high biocompatibility. This review aims to overview recent advances in applying different carbon allotrope composites in drug delivery-based cancer therapy systems.

The article presents the study results of the complex modification of eutectic silumin АК12М2МгН (AlSi12Cu2MgNi) with additives of fullerene-containing soot (FCS) and copper. It is shown that the effect on the alloy structure is caused by the introduction of carbon nanoparticles into the melt and is manifested in the dispersion of the structural phases and their uniform distribution in the casting volume. At the same time, the use of dispersed copper powder provides wetting of aluminum carbon particles with the melt and additional alloying of the melt. The formation of a dispersed structure leads to an increase in the mechanical and tribotechnical characteristics of the alloy: an increase in the ultimate strength (by 1.3–1.6 times) with a simultaneous increase in the relative elongation by up to 3 times, a significant decrease in the coefficient of friction (by 1.1–1.7 times) and the intensity of wear. The lowest coefficient of friction and high wear resistance are achieved at small fractions of FCS (0.05–0.1 wt.%) and the copper content in the modifier is not more than 0.5 wt.%.

Local quasiparticle states around impurities provide essential insight into the mechanism of unconventional superconductivity, especially when the candidate materials are proximate to an antiferromagnetic Mott-insulating phase. While such states have been reported in atom-based cuprates and iron-based compounds, they are unexplored in organic superconductors which feature tunable molecular orientation. Here we employ scanning tunneling microscopy and spectroscopy to reveal multiple forms of robustness of an exotic $s$-wave superconductivity in epitaxial Rb$_3$C$_{60}$ films against merohedral disorder, non-magnetic single impurities and step edges at the atomic scale. Also observed have been Yu-Shiba-Rusinov (YSR) states induced by deliberately incurred Fe adatoms that act as magnetic scatters. The bound states display abrupt spatial decay and vary in energy with the Fe adatom registry. Our results and the universal optimal superconductivity at half-filling point towards local electron pairing in which the multiorbital electronic correlations and intramolecular phonons together drive the high-temperature superconductivity of doped fullerenes., Comment: 25 pages, 5 figures, 5 supplemental figures

Controlled crystallization of fullerene molecules into ordered molecular assemblies is important for their applications. However, the morphology engineering of fullerene[C70 ] assemblies is challenging, and complicated architectures have rarely been reported due to the low molecular symmetry of C70 molecules, which makes their crystallization difficult to control and the low production yield as well. Herein, with the assistance of solvent intercalation, a general reprecipitation approach is reported to prepare morphologically controllable C70 microcrystals with mesitylene as a good solvent and n-propanol as a poor solvent in one solvent system without replacing specific solvents. A series of C70 microcrystals with high uniformity from perfect cubes and defective hoppers to novel cruciform-pillars are obtained by intentionally tuning C70 concentration and the volume ratio of mesitylene to n-propanol. Among them, novel cruciform-pillar-shaped microcrystals are obtained for the first time by further decreasing the amount of mesitylene in the solvent-intercalated microcrystals. Notably, the C70 concentration is a key parameter for the selective growth of C70 hopper, rather than the volume ratio of mesitylene to n-propanol. Interestingly, the hopper-shaped microcrystals exhibit excellent photoluminescence properties relative to those of cubes and cruciform-pillars owing to the enhanced light absorption, proving their potential applications in optoelectronic devices. This study offers new insights into the morphology-controlled synthesis of other micro/nanostructured organic microcrystals and the fine tuning of photoluminescence properties of organic crystals.

The well-known "shuttle effect" of the intermediate lithium polysulfides (LiPSs) and low sulfur utilization hinder the practical application of lithium-sulfur (Li-S) batteries. Herein, we describe a novel C60 -S supramolecular complex with high-density active sites for LiPS adsorption that was formed by a simple one-step process as a cathode material for Li-S batteries. Benefiting from the cocrystal structure, 100 % of the C60 molecules in the complex can offer active sites to adsorb LiPSs and catalyze their conversion. Furthermore, the lithiated C60 cores promote internal ion transport inside the composite cathode. At a low electrolyte/sulfur ratio of 5 μL mg-1 , the C60 -S cathode with a sulfur loading of 4 mg cm-2 exhibited a high capacity of 809 mAh g-1 (3.2 mAh cm-2 ). The development of the C60 -S supramolecular complex will inspire the invention of a new family of S/fullerenes as cathodes for high-performance Li-S batteries and extend the application of fullerenes.

Singular reaction events of small molecules and their dynamics remain a hardly understood territory in chemical sciences since spectroscopy relies on ensemble-averaged data, and microscopic scanning probe techniques show snapshots of frozen scenes. Herein, we report on continuous high-resolution transmission electron microscopic video imaging of the electron-beam-induced bottom-up synthesis of fullerene C-60 through cyclodehydrogenation of tailor-made truxene derivative 1 (C60H30), which was deposited on graphene as substrate. During the reaction, C60H30 transformed in a multistep process to fullerene C-60. Hereby, the precursor, metastable intermediates, and the product were identified by correlations with electron dose-corrected molecular simulations and single-molecule statistical analysis, which were substantiated with extensive density functional theory calculations. Our observations revealed that the initial cyclodehydrogenation pathway leads to thermodynamically favored intermediates through seemingly classical organic reaction mechanisms. However, dynamic interactions of the intermediates with the substrate render graphene as a non-innocent participant in the dehydrogenation process, which leads to a deviation from the classical reaction pathway. Our precise visual comprehension of the dynamic transformation implies that the outcome of electron-beam-initiated reactions can be controlled with careful molecular precursor design, which is important for the development and design of materials by electron beam lithography.

Topology of fullerenes, carbon nanotubes, and nanocones has considerable worth due to their effective applications in nanotechnology. These are emerging materials of practical application in gas storage devises, nanoelectronics devices, energy storage, biosensor, and chemical probes. The topological indices are graph invariant used to investigate the physical and chemical properties of the compounds such as boiling point, stability, and strain energy through associated chemical graph of the underlying compound. We computed recently modified Zagreb connection indices of nanocones CNC 4 n , CNC 5 n , and CNC 6 n and generalized our findings up to a large class of CNC k n . Topological characterization of nanocones via these indices is mathematically novel and assists to enable its emerging use in nanotechnology. For computation and verification of results, we use Mathematica software.

The structural and dynamical attributes of C60 chains inserted inside Single Walled carbon Nanotubes (SWNT) have been investigated by x-ray and neutron refraction, and inelastic neutron scattering (INS). The mensuration have been performed on a large mass of a very high quality carbon peapods sample. We showed that powder refraction could hardly give definitive response on the way the C60s are bonded inside SWNT. However, the comparison of the neutron-derived generalized compression of states (GDOS) of the inserted C60 peas with the GDOS of the same objects derived from lattice dynamics computations led to unambiguous results. The witnessing of excitations in the 8-15 meV span is a clear evidence for the presence strong bonds among C60s in the sample. In the same time, the witnessing of a very weak quasi-elastic signal may be relevant to rotational motions of C60 monomers inside the SWNT. These results suggest that peapods are built of a mixed phase of C60 monomers and C60 n-mers.

Vaseline (VM)–carbon nanostructure (CNS) model systems were studied by rheological and tribological methods. CNSs are represented by materials of various structures: multilayer oxidized graphene (Gr), single-wall (SWNTs) and multi-wall (MWNTs) carbon nanotubes, Taunit-M material, fullerene C60, and shungite nanocarbon. The concentration of CNSs was 0.5 or 1.0 wt %. The influence of the type and concentration of CNSs on rheological and tribological properties of VM–CNS systems has been investigated. The general conclusion for the performed tribological and rheological studies of VM–CNS systems can be considered as the following: an increase in the spatial dimension of the studied carbon allotropes improves the lubrication ability of the base Vaseline. Such influence probably is due to the decrease in the fracture energy of system and the decrease in the thixotropy time.

Carbon-based materials—such as graphene nanoribbons, fullerenes, and carbon nanotubes—elicit significant excitement due to their wide-ranging properties and many possible applications. However, the lack of methods for precise synthesis, functionalization, and assembly of complex carbon materials has hindered efforts to define structure–property relationships and develop new carbon materials with unique properties. To overcome this challenge, we employed a combination of bottom-up organic synthesis and controlled polymer synthesis. We designed norbornene-functionalized cycloparaphenylenes (CPPs), a family of macrocycles that map onto armchair carbon nanotubes of varying diameters. Through ring-opening metathesis polymerization, we accessed homopolymers as well as block and statistical copolymers constructed from “carbon nanohoops” with a high degree of structural control. These soluble, sp2-carbon-dense polymers exhibit tunable fluorescence emission and supramolecular responses based on composition and sequence. This work represents an important advance toward bridging the gap between small molecules and functional carbon-based materials., Well-defined polymeric carbon nanomaterials were prepared from norbornene-functionalized cycloparaphenylenes using a combination of bottom-up organic synthesis and controlled polymer synthesis.

Carbon is an element with extremely versatile bonding properties and theoretical calculations have suggested the possible existence of several hundred structural allotropes. Many, or even most, of these are predicted to be formed under conditions of high pressure and temperature. On the other hand, experimental high pressure studies have identified surprisingly few structural allotropes. In this paper, physical properties and structural transformations observed in high pressure experiments, at and above room temperature, are reviewed for a large number of solid carbon allotropes. The materials discussed include bulk carbon such as graphite, diamond, glass-like and amorphous carbon, two-dimensional graphene, and molecular carbon in the form of one-dimensional carbon nanotubes and zero-dimensional fullerenes. Results from recent studies on twisted graphene, graphdiyne, graphyne, carbon dots and other interesting all-carbon allotropes are also briefly described. Observed similarities and differences between the high pressure behavior and evolution of carbon materials are discussed. In spite of the enormous volume of experimental work carried out on these materials, few new structural allotropes have been identified and most carbon materials studied convert into diamond at sufficiently high temperature and pressure. Further theoretical work thus seems to be needed to elucidate possible transformation processes and transition paths for the many undiscovered allotropes proposed from calculations. In particular, it is recommended that, for every new allotrope predicted by theory, suitable precursors and transformation conditions should also be investigated. Efficient creation of new structural allotropes or functional materials based on pure carbon by high pressure methods should ideally start from designed, preassembled precursor structures or composites for which transition paths can be theoretically predicted.

In order to improve some performances of graphene, such as dispersibility in solvent and the ability to bind functional groups, it is necessary to modify graphene to prepare its derivatives. Graphene oxide (GO), as an important graphene derivative, was prepared by using strong oxidants, resulting in a significant reduction in its performances, such as electrical conductivity and mechanical properties. The key to the preparation of high-quality graphene derivatives is to properly introduce functional group while retaining the original conjugated structure of graphene. Here, we report a method for fabricating hydroxylated graphene (G-OH) by modifying the aromatic ring of graphene with hydroxyl radicals. G-OH was produced with a continuous conjugated system and exhibited n-type semiconductor properties. By changing the reaction time, the band gaps of G-OHs were adjusted from 0.72 to 1.88 eV. Compared with GO, the mechanical properties and thermal stability of G-OH have been greatly improved, which will greatly expand its application fields. The dispersing ability of G-OH in aqueous solution was much higher than that of graphene. This method could also be applied in modifying other carbon materials, such as carbon nanotube and fullerene, to fabricate novel functional materials.

Scanning tunneling microscopy, scanning tunneling spectroscopy (STM/STS), and X-ray photoelectron spectroscopy (XPS) were used in this study. The electronic density of states for fluorofullerene molecules on the surface of semiconductors and metals has been calculated ab initio. The behavior of fluorofullerene molecules with different stoichiometric compositions is considered. It has been found that a dipole molecule C $${}_{60}$$ F $${}_{18}$$ prefers to be oriented by fluorine atoms towards the semiconductor surface. For a metallic surface, the dipole moment can deviate from the direction of the normal to the surface, which is caused by the balance between the intermolecular interaction and the interaction between the molecule and the surface. Fluorofullerene molecules tend to lose fluorine atoms over time, which allows them to be used as a source of fluorine in the processes of fluorination of metallic surfaces and a local chemical reaction on the semiconducting surface.

Adsorption of 2,4,6-tribromoaniline (BA), 2,4,6-trifluoroaniline (FA) and 2,4,6-trichloroaniline (CA) onto the surface of coronene/fullerene/fullerene-like nanocages was investigated by theoretical...

We synthesized a polythiophene with methyl-branched side chains, poly(3-2-methylpentylthiophene) (P3MPT), and studied the thermal properties, morphology, optoelectrical properties, and photovoltaic performance of P3MPT blended with the fullerene derivative, [6,6]-phenyl C₆₀-butyric acid methyl ester (PCBM). The results are compared to those of the commonly used poly(3-hexylthiopene) (P3HT) with linear side chains to investigate the effects of the methyl-branched side chain. Differential scanning calorimetry (DSC) shows a higher glass transition temperature, and both X-ray diffraction and UV–vis absorption reveal a lower crystallization rate for P3MPT as compared to P3HT, due to the methyl-branched side chains that more efficiently suppress the chain mobility. Such behaviors can create an optimal as well as a stable structure for bulk-heterojunction solar cells so that the P3MPT/PCBM-based device not only shows a higher power conversion efficiency (PCE) but can much more effectively maintain the efficiency with time than the P3HT/PCBM-based device does. The stable phase-separated structure in the P3MPT/PCBM blend is confirmed by the grazing-incidence small-angle X-ray scattering (GISAXS) technique, which explains the superior long-term stability of the P3MPT/PCBM solar cell.

Carbon-based nanomaterials (fullerenes, carbon nanotubes, graphene derivatives, etc.) are promising cost-effective catalyst alternatives to noble metal catalysts for the oxygen reduction reaction (ORR). Herein, we report on the synthesis and characterization of graphene-based derivatives with various aspect ratios. All the synthesized materials were critically probed for activity and stability for ORR in acidic and alkaline electrolytes. Namely, a comparison study on the influence of aspect ratio and N-doping on ORR electroactivity in acidic and alkaline electrolytes of quasi-1D N-doped heat-treated graphene oxide nanoribbons (N-htGONr) with 2D N-doped heat-treated graphene oxides (N-htGO) was done. Moreover, we also investigated the influence of metallic impurities on the ORR activity in acidic and alkaline media. We have shown that a higher aspect ratio plays an important role in improving ORR activity. Furthermore, when comparing N-doped derivatives with non-doped derivatives, the ORR activity in 0.1 M HClO4 is increased by N-doping; however, in 0.1 M KOH, the N-doping effect is overshadowed by inherent transition metal impurities, i.e., iron. In this respect, we have established a linear correlation between onset potential for ORR, iron concentration, and BET specific surface area of graphene-based derivatives. The present study will aid in the critical assessment and development of non-metallic catalysts for the electrochemical energy conversion devices.

The hybrid systems based on the carbon nanotubes (CNT) and fullerenes (nanopipodes) are promising for applications in nanoelectronics. With insignificant variation of the CNT diameter the change of the fullerenes geometry takes place. The periodically located inside fullerenes represent a set of quantum points in the one-dimensional super-lattice. Using the variation of inside fullerenes it is possible to modulate the zone structure of the CNT – fullerene system and to control the electronic and phonon characteristics of nanopipodes. In the work the optical and thermoelectric properties of CNT with encapsulated molecules of C60 fullerene have been investigated. Using the first-principle methods the coefficients of absorption, optical conductivi-ty, thermal conductivity, thermoelectric figure of merit for CNT with fullerenes, periodically lo-cated inside the nanotubes at different distances from each other, have been calculated. It has been shown that with decreasing the distance between fullerenes the optical conductivity of CNT – C60 is suppressed at high frequencies. It has been determined that the conductance of the structures with fullerenes is less than the conductance of a clean tube, and approximately equal for considered distances (12.3 and 19.7 Å) between fullerenes. The CNT thermal conductivity due to the encapsulation of fullerenes considerably (3–4 times) decreases for the considered CNT (8.8) – C60 systems.

In the present paper the Euler approach which is generalised for the case of interaction of bodies with deformation is used to describe motions of dimers and unbound fullerenes inside a carbon nanotube. Frequencies and amplitudes of longitudinal vibrations of fullerenes and their dimers inside a CNT are calculated. The conditions under which the energy of rotational motion of a dimer can be transformed into the energy of its translational displacements are determined. This effect has an important application in medicine, specifically, in the sphere of targeted delivery of drugs where a nanotube plays the role of a molecular container.

Although fullerenes were discovered nearly 35 years ago, scientists still struggle to isolate "single molecule" tubular fullerenes larger than C90. In similar fashion, there is a paucity of reports for pristine single-walled carbon nanotubes (SWNTs). In spite of Herculean efforts, the isolation and properties of pristine members of these carbonaceous classes remain largely unfulfilled. For example, the low abundance of spherical and tubular higher fullerenes in electric-arc extracts (