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Hundreds of C60 derivatives stand out as electrontransporting materials(ETMs), for example, in perovskite solar cells(PSCs), due to their properties on electron extraction or defect passivation. However, it still lacks of guidelines to update C60-based ETMs with excellent photoelectric properties. In this work, crystallographic data of eight C60-based ETMs, including pristine C60 and the well-known PCBM as well as six newly synthesized fullerenes, are analyzed to establish the connections between derivatized structures and photoelectric properties for the typical carbon cluster of C60. In terms of packing centroid-centroid distance between neighboring carbon cages, the crystallographic data are useful for probing photoelectric properties, such as electrochemical properties, electron mobility and photovoltaic performances, and therefore facilitate to design novel C60-based ETMs for PSCs with high performances.

Endohedral clusterfullerenes featuring the encapsulation of metal clusters within carbon cages exhibit intriguing physical and chemical properties inaccessible to empty fullerenes. Thus far, their syntheses are predominantly fulfilled by using gaseous sources, suffering from low yield, and requiring an additional gas inlet and a heating pretreatment up to 1000 °C. Herein, we employ an ancient pigment, Prussian blue (Fe4[Fe(CN)6]3), as a cheap solid cyanide/nitrogen dual-source, affording the simplified yet high-yield simultaneous syntheses of novel dysprosium (Dy)-based metal cyanide clusterfullerenes (CYCFs) DyCN@C2n and metal nitride clusterfullerenes Dy3N@C2n. Surprisingly, the (CN)− anion of Fe4[Fe(CN)6]3 survives under the extremely high temperature (up to 4000 K) of plasma generated via DC-arc discharge, and functions as the cyanide source of CYCFs. Under the optimized Dy : [CN] : C molar ratio of 1 : 1 : 15, the sum yield of isolated DyCN@C2n (2n = 76, 82) CYCFs produced using Fe4[Fe(CN)6]3 is about 2.8 times higher than that obtained using gaseous N2 source. Moreover, the molecular structures of the three isomers of DyCN@C82 are unambiguously determined by single-crystal X-ray diffraction, indicating that the encapsulated triangular DyCN cluster is tunable due to strong metal–cage interactions. This study paves the way for the low-cost and high-yield syntheses of pricey endohedral fullerenes.

We report a chemical separation method to isolate fullertubes: a new and soluble allotrope of carbon whose structure merges nanotube, graphene, and fullerene subunits. Fullertubes possess single-wa...

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.

The combustion has long been applied for industrial synthesis of carbon materials such as fullerenes as well as carbon particles (known as carbon black), but the components and structures of the carbon soot are far from being clarified. Herein, we retrieve an unprecedented hydrofullerene C66H4 from a soot of a low-pressure combustion of benzene-acetylene-oxygen. Unambiguously characterized by single-crystal X-ray diffraction, the C66H4 renders a nonclassical geometry incorporating two heptagons and two pairs of fused pentagons in a C2 v symmetry. The common vertexes of the fused pentagons are bonded with four hydrogen atoms to convert the hydrogen-linking carbon atoms from sp2 to sp3 hybridization, which together with the adjacent heptagons essentially releases the sp2-bond strains on the abutting-pentagon sites of the diheptagonal fused pentagon C66 (dihept-C66). DFT computations suggest the possibility for an in situ hydrogenation process leading to stabilization of the dihept-C66. In addition, the experiments have been carried out to study heptagon-dependent properties of dihept-C66H4, indicating the key responsibility of the heptagon for changing hydrocarbon activity and electronic properties. The present work with the unprecedented double-heptagon-containing hydrofullerene successfully isolated and identified as one of the low-pressure combustion products shows that the heptagon is a new building block for constructing fullerene products in addition to pentagons and hexagons in low-pressure combustion systems.

Full-printable all-inorganic mesoporous network has emerged as a promising device scaffold for perovskite photovoltaic applications because of its highly stable device architecture and essentially scalable fabrication process, but practical application of this photovoltaic technology requires further advancement on power conversion efficiency. Here we introduce a facile oxygen management strategy in the carbon electrode (CE) to simultaneously tune energy alignment and the interface contact between perovskite and the CE. Augmenting the oxygen content of carbon black in CE not only elevates the energy level of the CE, but also optimizes the perovskite/CE interface contact, leading to a significantly enhanced hole extraction efficiency at the interface of perovskite/CE. These enable us to fabricate solar cells possessing a maximum efficiency of 15.7% benefiting from open-circuit voltage enhancement of 100 mV, which is significantly higher than that of control device (13.6%) without oxygen management in the CE. The present work diversifies a strategy to optimize the energy level alignment and interface contact of the perovskite/CE for the efficient printable mesoscopic perovskite solar cells.

High-performance and cost effective electrocatalysts used for oxygen evolution reactions (OER) are indispensable in renewable-energy technologies. As an important 3D class of porous materials, Metal organic frameworks (MOF) with designable topological structures and compositions have been used as templates to obtain diverse functional materials. In this paper, ZnCo2O4@C-MWCNTs has been successfully synthesized by embedding dual-MOF into MWCNTs followed by calcinations under N2 and air atmosphere in turn. The ZnCo2O4@C-MWCNTs hybrid exhibits enhanced OER performance in terms of an onset potential (1.45 V vs. RHE) and a low overpotential (327 mV) at 10 mA cm−2. It is noteworthy that the potentials of ZnCo2O4@C-MWCNTs remain almost constant for 25 h in alkaline solution. Compared with many MOF derived matrix for OER applications, in-situ carbon formed during calcination process under N2 atmosphere can not only improve the material's conductivity, but also prevent the agglomeration of active nanoparticles. The design concept of dual-MOFs-doped MWCNTs can be significantly expanded to fabricate other novel and stable catalysts for a wide range of applications.

Previously, we have reported that different procedures employed for electrochemical oxidation of glassy carbon (GC) can lead to remarkably different interfaces for the redox reactions of copper species in the presence of Cl− anion. In this article, we further investigated the interfacial variation mechanism of other carbon electrodes employing both cyclic and potentiostatic oxidation methods in H2SO4 solution. The electrochemical studies were limited to the end-edge planes of vertically aligned multi-walled carbon nanotubes (eVAMWCNTs) and the edge planes of highly oriented pyrolytic graphite (eHOPG). Differences in the pristine surfaces and bulk structures of these two sp2 carbon electrodes were merely resulted from the arrangements of graphene multilayers by rolling seamlessly or parallel alignment. Experimental results showed that cyclic oxidation favored the generation of oxygen-containing groups at eVAMWCNTs, due to that rigid MWCNT surface and bulk structures were unfavorable for the intercalation reaction of SO42 − anion. On the other hand, potentiostatic oxidation was found to cause the oxidation of eVAMWCNTs via a different reaction route. By contrast, the oxidation of the soft eHOPG predominantly involved the intercalation of SO42 − anion into the gaps between graphene layers, which might restrain the increase of oxygen-containing groups at eHOPG. As probed by Raman spectroscopy and the redox reactions of copper species, significant differences in the interfacial variation with two oxidation methods were observed for eVAMWCNTs. As indicated by an abnormal behavior of metallic copper deposition/dissolution, only the cyclic oxidation could quickly generate a very high ratio of oxygen-containing groups to other electron transfer sites (edge steps and defect sites) at the eVAMWCNT interfaces, similar to the previous observations for GC. Due to limitation in the increase of oxygen-containing groups at the eHOPG interfaces, two oxidation methods would not cause significant differences in the electrode responses for the redox reactions of copper species.

Full-carbon electronics at the scale of several angstroms is an expeimental challenge, which could be overcome by exploiting the versatility of carbon allotropes. Here, we investigate charge transport through graphene/single-fullerene/graphene hybrid junctions using a single-molecule manipulation technique. Such sub-nanoscale electronic junctions can be tuned by band gap engineering as exemplified by various pristine fullerenes such as C60, C70, C76 and C90. In addition, we demonstrate further control of charge transport by breaking the conjugation of their π systems which lowers their conductance, and via heteroatom doping of fullerene, which introduces transport resonances and increase their conductance. Supported by our combined density functional theory (DFT) calculations, a promising future of tunable full-carbon electronics based on numerous sub-nanoscale fullerenes in the large family of carbon allotropes is anticipated., All-carbon electronics holds promise beyond the conventional silicon-based electronics, but it remains challenging to manufacture them with well-defined structures thus tunability. Tan et al. control charge transport in single-molecule junctions using different fullerenes between graphene electrodes.

High quality graphene materials that readily disperse in water or organic solvents are needed to achieve some of the most ambitious applications. However, current synthetic approaches are typically limited by irreversible structural damages, little solubility, or low scalability. Here, we describe a fundamental study of graphene chemistry and covalent functionalization patterns on sp2 carbon lattices, from which a facile, scalable synthesis of high quality graphene sheets was developed. Graphite materials were efficiently exfoliated by reductive, propagative alkylation. The exfoliated, propagatively alkylated graphene sheets (PAGenes) not only exhibited high solubility in common solvents such as chloroform, water, and N-methyl-pyrrolidone, but also showed electrical conductivity as high as 4.1 × 103 S/m, which is 5 orders of magnitude greater than those of graphene oxides. Bright blue photoluminescence, unattainable in graphene, was also observed. We attribute the rise of blue photoluminescence in PAGenes...

Curvature prevalently exists in the world of carbon materials (e.g., fullerenes, buckyl bowls, carbon nanotubes, and onions), but traditional C2-addition mechanisms fail to elucidate the mechanism responsible for the formation of carbon curvature starting from a pentagonal carbon ring in currently available chemical-physical processes such as combustion. Here, we show a complete series of nascent pentagon-incorporating C5-C18 that are online produced in the flame of acetylene-cyclopentadiene-oxygen and in situ captured by C60 or trapped as polycyclic aromatic hydrocarbons for clarifying the growth of the curved subunit of C20H10. A mechanism regarding C1-substitution and C2-addition has been proposed for understanding the formation of curvature in carbon materials, as exemplified by the typical curved molecule containing a single pentagon completely surrounded by five hexagons. The present mechanism, supported by the intermediates characterized by X-ray crystallography as well as NMR, has been experimentally validated for the rational synthesis of curved molecule in the commercially useful combustion process.

Pure non-IPR (isolated-pentagon-rule) C 60 isomer has rarely been investigated experimentally. The recently reported availability of #1809 C 60 Cl 8 opens an avenue for experimental investigation of #1809 C 60 , a C 2v -symmetric C 60 isomer having two pairs of fused pentagons. Herein, the experiments on #1809 C 60 were performed on the basis of thermal dechlorination of #1809 C 60 Cl 8 in the solid state and gas phase. #1812 C 60 Cl 6 was employed for comparative study. As determined by Raman and other methods, #1809 C 60 from thermal decomposition of #1809 C 60 Cl 8 crystals readily coalesces to form carbon solid with a collapsed crystal lattice. In contrast, dechlorination via thermal spray of #1809 C 60 Cl 8 in the gas phase is feasible for investigation of monodispersed all-carbon C 60 isomer, because the existence of #1809 C 60 in the gas phase has been confirmed by experimental evidence from mass spectrometry and high-performance-liquid-chromatography.

The most stable fullerenes obey the isolated-pentagon rule (IPR): hexagons of carbon atoms entirely surround pentagons to minimize strain. Recently, some examples of fused-pentagon fullerenes have been reported and this Review summarizes current work to stabilize non-IPR fullerenes. The isolated pentagon rule (IPR) is now widely accepted as a general rule for determining the stability of all-carbon fullerene cages composed of hexagons and pentagons. Fullerenes that violate this rule have been deemed too reactive to be synthesized. The stabilization of non-IPR endohedral fullerenes depends on charge transfer from the encapsulated metal clusters (endoclusters) to fullerene cages, the electronic properties of empty all-carbon cages, the matching size and geometries of fullerene and endocluster, as well as the strong coordination of the metal ions to fused pentagons. The stability of non-IPR exohedral fullerenes can be rationalized primarily by both the 'strain-relief' and 'local-aromaticity' principles. This Review focuses on recent work on stabilization of non-IPR fullerenes, including theoretical and empirical principles, experimental methods, and molecular structures of fused-pentagon fullerenes characterized so far. The special chemical properties of non-IPR fullerenes that distinguish them from IPR-satisfying ones are also emphasized.

Microwave-modified activated carbon fiber (ACF-1), nitric acid-modified activated carbon fiber (ACF-2), phosphoric acid-modified activated carbon fiber (ACF-3) and ammonia-modified activated carbon fiber (ACF-4) were successfully fabricated. The electro-Fenton catalytic activities of modified activated carbon fiber were evaluated using phenol as a model pollutant. H2O2 formation, COD removal efficiency and phenol removal efficiency were investigated compared with the unmodified activated carbon fiber (ACF-0). Results indicated that ACF-1 showed the best adsorption and electrocatalytic activity. Modification was in favor of the formation of H2O2. The performance of different systems on phenol degradation and COD removal were ACF-1ACF-3ACF-4ACF-2ACF-0 and ACF-1ACF-4ACF-3ACF-2ACF-0, respectively, which confirmed that electrocatalytic activities of modified activated carbon fiber were better than the unmodified. In addition, phenol intermediates were not the same while using different modified activated carbon fibers.

The detection of nanotube carbons in solution by (13)C NMR is reported. The highly soluble sample was from the functionalization of (13)C-enriched single-walled carbon nanotubes (SWNTs) with diamine-terminated oligomeric poly(ethylene glycol) (PEG(1500N)). The ferromagnetic impurities due to the residual metal catalysts were removed from the sample via repeated magnetic separation. The nanotube carbon signals are broad but partially resolved into two overlapping peaks, which are tentatively assigned to nanotube carbons on semiconducting (upfield) and metallic (downfield) SWNTs. The solid-state NMR signals of the same sample are similarly resolved. Mechanistic and practical implications of the results are discussed.

通讯作者地址: Xie, ZX (通讯作者), Xiamen Univ, Dept Chem, State Key Lab Phys Chem Solid Surfaces, Siming Nanlu 422, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Dept Chem, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 电子邮件地址: zxxie@xmu.edu.cn

通讯作者地址: Xie, SY (通讯作者), Xiamen Univ, Dept Chem, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Dept Chem, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 2. Wuhan Univ, Dept Chem, Wuhan 430072, Peoples R China

Simultaneous separation and identification of perchlorinated polycyclic aromatic hydrocarbons (PCPAHs) and fullerenes is of practical interest due to the growth mechanism of fullerenes involved with PCPAHs. Non-aqueous reversed-phase high-performance liquid chromatography (HPLC), with an ODS column and a gradient mobile phase of methanol-ethanol-cyclohexane mixtures, was combined with both rapid-scan ultraviolet spectrometry (UV) and atmospheric pressure chemical ionization mass spectrometry (APCI-MS) for the separation and identification of over 80 PCPAHs as well as fullerenes C60 and C70, that were synthesized in the discharge reaction of chloroform. PCPAH retention was found to depend on the number of aromatic rings and the degree of non-planarity of PCPAH structure. Based on the isotopic pattern of molecular ion or/and quasi-molecular ion peaks in corresponding mass spectra, molecular compositions of the PCPAH products were unambiguously determined. The results obtained from the HPLC-UV-MS analysis not only are helpful for the understanding of the fullerenes formation mechanism, but also contribute to the analytical technique capable of separating and identifying the complicated mixture of PCPAHs and fullerenes.

In addition to I h symmetry buckminsterfullerene, four other isomers of C 60 were generated in a microwave plasma of chloroform. The newly observed isomers, separated and identified by a high performance liquid chromatography coupled with mass spectrometry (HPLC–MS), were found to be stable at room temperature but transform to buckminsterfullerene when heated. With regards to the generation of various fully chlorinated carbon clusters as well as the C 60 isomers, which may be attributed to the rapidly cooling of the synthetic reaction, a modified Pentagon Road scheme is suggested for fullerene formation.

Perchloroacenaphthylene(C12Cl8), a perchlorinated polycyclic hydrocarbon composed of two hexagons and a pentagon, was ablated by a pulsed laser beam in a vacuum. The products created from the laser ablation were characterized by high-performance liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometry and rapid-scan ultraviolet spectrophotometric detection. Buckminsterfullerene C60 and various perchlorinated carbon clusters have been observed among the products. The observation is helpful for understanding the formation mechanisms of fullerenes and suggests that the Pentagon Road scheme is feasible with the involvement of chlorines.

通讯作者地址: Xie,SY(通讯作者),Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, 422 Si Ming Rd, Xiamen 361005, Peoples R China

A long-sought empty non-IPR fullerene, (#11188)C72, which is more stable than the sole IPR isomer in the fullerene[72] family, has been retrieved and crystallographically characterized as (#11188)C72Cl4. Mass spectrometric data support the facile dechlorination of (#11188)C72Cl4 and, in turn, the possible stability of pristine (#11188)C72.

The most stable fullerenes obey the isolated-pentagon rule (IPR): hexagons of carbon atoms entirely surround pentagons to minimize strain. Recently, some examples of fused-pentagon fullerenes have been reported and this Review summarizes current work to stabilize non-IPR fullerenes. The isolated pentagon rule (IPR) is now widely accepted as a general rule for determining the stability of all-carbon fullerene cages composed of hexagons and pentagons. Fullerenes that violate this rule have been deemed too reactive to be synthesized. The stabilization of non-IPR endohedral fullerenes depends on charge transfer from the encapsulated metal clusters (endoclusters) to fullerene cages, the electronic properties of empty all-carbon cages, the matching size and geometries of fullerene and endocluster, as well as the strong coordination of the metal ions to fused pentagons. The stability of non-IPR exohedral fullerenes can be rationalized primarily by both the 'strain-relief' and 'local-aromaticity' principles. This Review focuses on recent work on stabilization of non-IPR fullerenes, including theoretical and empirical principles, experimental methods, and molecular structures of fused-pentagon fullerenes characterized so far. The special chemical properties of non-IPR fullerenes that distinguish them from IPR-satisfying ones are also emphasized.

Carbon nanotubes (CNTs) have been widely studied as a electron emitting sources of thin cold cathode[1]. Screen printed technology has advantage of large size display, easy process and low cost[2], hence it attracts much more attention than other traditional method in the fabrication of CNT-FED. However, due to random distribution of CNTs in printed cathode film, poor luminance and emission uniformity have hindered the further commercial development of CNT-FED.

Carbon nanoparticles upon simple surface passivation exhibit bright photoluminescence. Reported here is a new finding that these carbon dots are also strongly two-photon luminescent with pulsed laser excitation in the near-infrared. The experimentally measured two-photon absorption cross-sections are comparable to those of the high-performance semiconductor quantum dots already available in the literature. The two-photon luminescence microscopy imaging of human breast cancer cells with internalized carbon dots is demonstrated.

We report that nanoscale carbon particles (carbon dots) upon simple surface passivation are strongly photoluminescent in both solution and the solid state. The luminescence emission of the carbon dots is stable against photobleaching, and there is no blinking effect. These strongly emissive carbon dots may find applications similar to or beyond those of their widely pursued silicon counterparts.

Addition of a small quantity (∼3%) of CCl4 to the He atmosphere of the graphite arc-discharge reaction revealed a marked increase in fullerene yield.