Fullerenes and derivatives as electrocatalysts: Promises and challenges

Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion technologies.Of paramount significance are the establishment of design principles by understanding the catalytic mechanisms and identifying the active sites.Distinct from sp2-conjugated graphene and carbon nanotube,fullerene possesses unique characteristics that are growingly being discovered and exploited by the electrocatalysis community.For instance,the well-defined atomic and molecular structures,the good electron affinity to tune the electronic structures of other substances,the intermolecular self-assembly into superlattices,and the on-demand chemical modification have endowed fullerene with incomparable advantages as electrocatalysts that are otherwise not applicable to other carbon ma-terials.As increasing studies are being reported on this intriguing topic,it is necessary to provide a state-of-the-art overview of the recent progress.This review takes such an initiative by summarizing the promises and challenges in the electrocatalytic applications of fullerene and its derivatives.The content is structured according to the composition and structure of fullerene,including intact fullerene(e.g.,fullerene composite and superlattices)and fullerene derivatives(e.g.,doped,endohedral,and disintegrated fullerene).The synthesis,characterization,catalytic mechanisms,and deficiencies of these fullerene-based materials are explicitly elaborated.We conclude it by sharing our perspectives on the key aspects that future efforts shall consider.

Fullerenes的光化学与光物理性质

本文对Fullerenes自发现以来在光化学和光物理领域的研究进展,以及它的分离方法进行了综述。

Pt/onion-like fullerenes as catalyst for direct methanol fuel cell

Onion-like fullerenes synthesized by arc discharge in water were used as support of Pt nanoparticles as electrocatalytic materials for direct methanol fuel cell. Uniform platinum nanoparticles with the average diameter of about 4.3 nm were well dispersed on the surface of onion-like fullerenes by impregnation-reduction method. The morphologies and microstructures of the as-prepared composites were studied by means of XRD and TEM. Electrochemical analysis shows that this kind of nano material may be an excellent candidate to be used as the support of catalyst for methanol electrochemical oxidation.

Fullerenes中文定名的建议

一）Ｆｕｌｅｒｅｎｅｓ一词仍无令人满意的中文译名，我们曾经建议采用“球碳”或“”的译名，下面先简述提出“球碳”为译名的理由。（１）Ｆｕｌｅｒｅｎｅｓ只含碳元素，是石墨和金刚石的同素异形体，不是化合物，因此称其为“某某碳”是合情合理的。“某某碳”按汉...

BET Surface Area and Porous Structure of Fullerenes and Fullerene Soots

ＩｎｔｒｏｄｕｃｔｉｏｎＡｆａｓｃｉｎａｔｉｎｇｓｏｌｉｄｂｌａｃｋｃｏｎｄｅｎｓａｔｅ（ｈｅｒｅｃａｌｅｄｆｕｌｅｒｅｎｅｓｏｏｔ）ｉｓｇｅｎｅｒａｔｅｄｉｎｔｈｅｇａｓｐｈａｓｅａｎｄｄｅｐｏｓｉｔｅｄｄｕｒｉｎｇｔｈｅｄｉｓｃｈａｒｇｅｉｎａＫ...

Different Charging-Induced Modulations of Highest Occupied Molecular Orbital Energies in Fullerenes in Comparison with Carbon Nanotubes and Graphene Sheets

The highest occupied molecular orbital(HOMO) energies of fullerenes are found by quantitative first-principles calculations to be raised by negative charging, and the rising rate rank of the fullerenes is C_(60) >C_(70) >C_(80) >C_(90)>C_(100) >C_(180). Then we compare fullerenes with carbon nanotubes(CNTs) and graphene sheets(GSs) and find that the increase of the HOMO energy of a fullerene is much faster than that of CNTs and graphene sheets with the same number of C atoms. The rising rate rank is fullerene>CNT>GS, which holds no matter what the number of C atoms is or which structure the fullerene isomer is. This work paves a new path for developing all-carbon devices with low-dimensional carbon nanomaterials as different functional elements.

Properties of Boron-Substituted Heterofullerenes

On the basis of a succinct description of geometrical configurations for giant fullerenes,the electronic properties and structural distortions of heterofullerenes C_(N-1)B(N=60,180,240,420,540,720,780)are analyzed by the extended Su-Schrieffer-Heeger model.In comparison with their pristine fullerenes CN,local distortions and mid-gap states are found to occur in boron-doped giant fullerenes.

On the ECI and CEI of Boron-Nitrogen Fullerenes

The eccentric connectivity index and connective eccentricity index are important topological indices for chemistry. In this paper, we investigate the eccentric connectivity index and connective eccentricity index of boron-nitrogen fullerenes, respectively. And we give computing formulas of eccentric connectivity index and connective eccentricity index of all boron-nitrogen fullerenes with regular structure.

Single Covalent Bonding Structure in Fullerenes, Carbon Nanotubes and Closed Nanotubes

The present paper deals with carbon in highly organized solids like graphene and its three-dimensional derivatives: fullerenes, carbon nanotubes and capped carbon nanotubes. It proposes an alternative to the typical bonding pattern exposed in literature. This novel bonding pattern involves alternating positively and negatively charged carbon atoms around hexagonal rings, then a few uncharged and partially bonded atoms close to the pentagon rings. The article focuses on fullerenes inscribed into a regular icosahedron, then addressing the most common fullerenes like C60. Carbon atoms are found to have predominantly three single bonds and less often two separated single bonds. The same pattern explains equally well carbon nanotubes and closed-tip nanotubes, of which C70 is a special case.

Quantum Chemical Studies of Endofullerenes (M@C_(60)) Where M = H_(2)O, Li^(+), Na^(+), K^(+), Be^(2+), Mg^(2+), and Ca^(2+)

Quantum chemical calculations were performed to investigate the structural and electronic properties of seven endofullerenes. The interaction energies indicated that all of the chemical species are stable inside the fullerene for each complex. The ionization potential and electron affinity values suggest that the endofullerenes consisting of alkaline earth ions are the most reactive and that the dipole moment decreased according to the following order: Be2+@C60 (4.75) > Mg2+@C60 (3.14) > Ca2+@C60 (2.24) > Li+@C60 (1.26) > Na+@C60 (0.76) > H2O@C60 (0.24) > K+@C60 (0.00 Debye). These results imply that the solubility of endofullerenes in a polar solvent may increase from H2O@C60 to Be2+@C60. The energetic gaps indicate that Be2+@C60 and Mg2+@C60 possess a higher electrical conductivity, and the UV spectra show a shift in the bands to the visible light region. The results of this work may be useful for the development of new endofullerenes.

Fullerenes for rechargeable battery applications:Recent developments and future perspectives

The development of high-performance batteries is inseparable from the exploration of new materials.Among them,fullerene C60 as an allotrope of carbon has many unique properties that are beneficial for battery applications,including precise structure,controllable derivatization,good solubility,and rich redox chemistry.In this review,we summarize the recent progress of fullerene-based materials in the field of rechargeable batteries and the key issues that need to be solved in the future application of fullerene.We hope this review can provide guidance and stimulate research about the applications of fullerenes in the field of energy storage.

APPLICATION OF FULLERENES TO THE STUDY ON ITIES Ⅰ:INHIBITION TO THE TRANSFER OF TMA^+

For the first time,fullerenes are applied to the study on the interface between twoimmisible electrolyte solutions.Experiments show they are a new kind of inhibitors.Obvious inhibitive behavior to the TMA^+ transfer across the water/nitrobenzeneinterface is observed.

HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC SEPARATION OF FULLERENES

High-performance liquid chromatographic systems for the separation of buckminsterfullerene(C60) and related fullerene C70 were investigated with methanol/benzene or methanol/toluene （35/65-60/40 in Ⅴ/Ⅴ） as eluant in C18 reversed phase column. The system is suitable for fast analysis of fullerenes at lower percentage of methanol, and repeatly large scale perparation at higher percentage of methanol.

The Development of Fullerenes in Cosmetics from Domestic and Worldwide Patent Data

Fullerene is an excellent anti-aging raw material for cosmetic industry,which has strong free radical scavenging ability.Current work on fullerene has been mostly focused on its applications and properties,but there are few studies on the patents regarding its application in cosmetics.Herein,the development of fullerene in its application in cosmetics was analyzed by searching the patents regarding fullerene in cosmetic industry in the databases from China National Intellectual Property Administration and European Patent Office.The main technical fields of patents,the applicants and inventors,the publication date and the region were analyzed.Data comparison was also conducted according to above aspects at home and abroad.It was found that fullerene-containing cosmetics in China was generally consistent with the world level.China started a little later than other countries in terms of time;there are quality problems worldwide,e.g.,the lack of technical innovation.Most patents mainly related to appearance or packaging.As the second largest patent applicant country for fullerene-containing cosmetics in the world,China obviously has leading advantage in terms of quantity.Among the applicant regions being considered,fullerene industry giants such as Japanese Mitsubishi are the main ones.Due to the late start of domestic enterprises,there is still a big gap with the world’s leading groups.However,in cosmetics industry,it can be said that domestic enterprises have taken the initiative when contrasted with traditional overseas brands.

ScY@C_(3v)(8)-C_(82):Metal-Metalσ^(2)Bond in Mixed Rare-Earth Di-metallofullerenes

Comprehensive Summary The experimental investigation of rare-earth metal-metal bonds remains a challenge in the study of chemical bonds.Herein,we report the synthesis and characterization of a novel heteronuclear di-metallofullerene,ScY@C_(3v)(8)-C_(82),which contains a mixed rare-earth metal-metal bond.ScY@C_(3v)(8)-C_(82)was successfully synthesized by arc-discharging method and characterized by mass spectrometry,UV-vis-NIR spectroscopy and single-crystal X-ray diffraction crystallography,which unambiguously determined its molecular structure.Theoretical calculations were also performed to study the optimized positions of Sc-Y metallic dimer and the electronic configuration.The combined experimental and theoretical results confirmed that both Sc and Y atoms transfer two electrons to the C_(3v)(8)-C_(82)cage,i.e.,(ScY)4+@(C_(3v)(8)-C_(82))4-.In particular,a covalent Sc-Yσ2 bond,which has never been reported before,is proven to be formed inside C_(3v)(8)-C_(82)fullerene cage.This work presents a novel di-metallofullerene containing mixed rare-earth metal-metal bond and expands the understanding of metal-metal bonding of rare earth elements.

Recent Advances in Functionalized Fullerenes in Perovskite Solar Cells

Comprehensive Summary,Efficient charge transport and defect passivation are essential for high efficiency of organic–inorganic hybrid perovskite solar cells(PSCs).Functionalized fullerenes featuring high electron affinity and mobility as well as small reorganization energy have been extensively applied in PSCs toward facilitated electron transport and passivated trap states,leading to improvements of both device efficiency and stability.Herein,we summarize the recent advances,especially in the last three years,in applications of functionalized fullerenes including fullerene derivatives and endohedral metallofullerenes in PSCs.Their functions in trap state passivation,electron transport promotion,crystalline modulation,water/oxygen erosion inhibition,and so on,are discussed in details.In particular,we emphasize novel functions of fullerenes beyond trap state passivation,as well as the synergy of multifunction of fullerenes in improving PSC device performance and stability.Finally,we present an outlook on designing novel multifunctionalized fullerenes toward highly efficient and stable PSC devices.

Advances in Regioselective Functionalization of Endohedral Metallofullerenes

Comprehensive Summary Endohedral metallofullerenes(EMFs)are a family of molecules with metal clusters or ions encapsulated inside a fullerene cage.Their unique structures provide a powerful interface for organic chemists to manipulate metal elements.Over a decade ago,many reactions on empty fullerenes were adopted for EMFs,resulting in a series of reactions that are well-established and reviewed in the literature.In recent years,new topics have emerged in EMF chemistry.First,new addition reactions were developed,notably some that are not based on known empty-fullerene reactions.Second,considerable progress has been made on regioselective multi-additions on EMFs.

Synthesis of Diverse 1,4-(Azaindole)[60] fullerenes via Transition- Metal Free Three-Component Coupling Reaction of Azaindoles, C_(60), and Bromoalkanes/Triphenylamines

A transition-metal free three-component coupling reaction of azaindoles,C_(60),and bromoalkanes/triphenylamines has been developed to provide an efficient access to diverse azaindole functionalized 1,4-C_(60) adducts.This protocol exhibits low cost,operational simplicity,wide substrate scope,and mild and convenient conditions.

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

Hydrogen-bonded capsules have been widely employed as supramolecular hosts for organic molecular guests.Encapsulation of fullerenes by capsules is relatively scarce,especially those that utilize sulfur atoms as hydrogen-bond acceptors.Herein,we describe,in both solution and solid state,a bowl-shaped nanobelt[8]cyclophenoxathiin 1a and its tetra-methylated derivative 1b that can form C–H⋯S hydrogen-bonded capsules induced by complexation with suitable fullerenes.1a strongly encapsulates C60,C70,or 6,6-phenyl-C61-butyric acid methyl ester(PC61BM)to form a 2∶1 ternary complex featuring 16 equatorial(sp2)C–H⋯S hydrogen bonds.A pseudorotaxane structure was further obtained for the complex of 1a with PC61BM.Conversely,a 1∶1 inclusion complex was observed for binding C60 or PC61BM with 1b indicating the reduced tendency to form capsules by introducing methyl groups into the belt.Surprisingly,the capsule-like structure was retained for the 1:2 complex of C70 with 1b as observed by the presence of multiple(sp3)C–H⋯S hydrogen bonds.The strong binding affinity and tailorable complexation mode enable further applications of nanobelts in fullerene chemistry.