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.

New Approaches of Theoretical Astrophysics for Application to Some Astronomical Objects: I. An Application of Non-Classical Equation Mathematical Physics to the Magneto-Hydrodynamic Equilibrium (in Case of Mixed Magnetic Field) of Magnetic Stars

In this paper, we consider the application of the equation of non-classical mathematical physics to magneto-hydrodynamic equilibrium (in the case of a mixed magnetic field) for magnetic stars. First, we give the necessary concepts about the equation of non-classical mathematical physics and the possibility of their applicability to astrophysical problems. The conditions of magneto-hydrodynamic equilibrium are determinate, and self-consistence provides the means to derive the corresponding partial differential equations describing this equilibrium in a magnetosphere magnetic star. Namely, this process is to the non-classical equations of mathematical physics in cases of types. Keldysh-Tricomi, a common case equation of non-classical type, is at first introduced by the author. Using the two main physical efficiencies of MHD. A mathematical model of a poloidal-toroidal mixed magnetic field for magnetic stars is constructed, and this model is classified with respect to degenerating case equations. According to Hopf’s theorem, Maxwell’s equation and the magnetic force balance equation constructed equilibrium conditions of the poloidal-toroidal of the magnetic field for a magnetic star. At the same time, the taken example, which is the self-consistency of this model by observation dates, is investigated. At first, in an application, the method of straight lines for recurrent formulas of calculation of magnetic flux and stream functions is used. The physical means, the corresponding singular point of the sonic line, cutoff, and resonance phenomena are considered. In this case, a general solution equation is found, which is interpreted by this phenomenon as a cutoff, resonance. Finally, this obtained solution gives the conditions of magneto-hydrodynamic equilibrium on the magnetosphere of magnetic stars. Methodology and obtained equations are new approaches that are at first considered.

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...

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。

Fullerenes分子的键构规则

Fullerenes分子是科学家在研究碳原子簇过程中发现的一类崭新的有机分子,简单情形是C60。Fullerenes及其衍生物为碳化学打开了—个广阔天地,同时也为固体物理学提供了一个新的研究领域。它还将为材料科学带来新的机会。尽管化学家和物理学家为这类新奇的原子簇勾画了许多理论图象,但关于其键构的—般性规则的研究仍然太少。

Determination of Fullerenes (C60/C70) from the Permian-Triassic Boundary in the Meishan Section of South China

Fullerenes (C 60 /C 70 ), clays and rocks near the Permian-Triassic (P/T) boundary in the Meishan section of South China are explored by means of comprehensive analytical techniques, including ultrasonic extraction with column purification, high-performance liquid chromatography (HPLC) and matrix assisted laser desorption/ionization time-of- flight mass spectrometry (MALDI TOF MS). The study confirms the existence of fullerenes toward the P/T event boundary and their absence in clays and limestones beyond the boundary. In particular, the white clay, known as the event boundary, contains fullerenes of 0.33 ppb, while the red material, as the first lamina fill of goethite and gypsum on the base of the white clay, contains fullerenes of 1.23 ppb, and the last lamina of 2.50 ppb. Significantly, distinct enrichment of fullerenes is coincident with the disappearance of fossil records of marine species (94%) just at the base of the white clay, implying that geological fullerenes would be one of temporal remnants led by the P/T catastrophic event. This work strongly supports that fullerenes would be one of significant records of the P/T catastrophic event but their origin remains to be studied further.

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.

Non-classical phenotypes of autoimmune hepatitis and advances in diagnosis and treatment

Non-classical manifestations of autoimmune hepatitis can delay diagnosis and treatment. Our aims were to describe the clinical phenotypes that can confound the diagnosis, detail scoring systems that can ensure their recognition, and outline advances in treatment that can improve their outcome. Prime source and review articles in English were selected throuqh Medline from 1970-2008 and assimilated into personal libraries spanning 32 years. Acute severe or asymptomatic presentations and atypical histological findings,including centrilobular zone 3 necrosis and concurrent bile duct changes, are compatible with the diagnosis. Cholangiographic abnormalities may be present in children and adults with the disease, and autoimmune hepatitis must be considered in patients without autoantibodies or with antimitochondrial antibodies and no other cholestatic features. Asymptomatic patients frequently become symptomatic; mild disease can progress; and there are no confident indices that justify withholding treatment. Two diagnostic scoring systems with complementary virtues have been developed to evaluate patients with confusing features. Normal liver tests and tissue constitute the optimal end point of treatment, and the first relapse is an indication for long- term azathioprine therapy. Cyclosporine, tacrolimus and mycophenolate mofetil are promising salvage therapies,and budesonide with azathioprine may be a superior frontline treatment. We conclude that the non-classical phenotypes of autoimmune hepatitis can be recognized promptly, diagnosed accurately, and treated effectively.

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.

New Solution Method of Pi-Orbital Axis Vector and Its Applications in Fullerenes and Carbon Nanotubes

A new solution method to perform the pi-orbital axis vector analysis was developed in this paper. The model of circular cone was built and the solution equations of the pyramidalization angle were obtained based on the model and the space analytic geometry. Our method merely requires the atomic coordinates of the conjugated central atom and the three attached atoms. Moreover, systematic calculations on the pyramidalization angles of fullerenes and carbon nanotubes were performed using the method we developed. The relationship of pyramidalization angle and the stability for the carbon cages and tubes was also discussed.

High stability of the goldalloy fullerenes:A density functional theory investigation of M_(12)@Au_(20)(M=Na,Al,Ag,Sc,Y,La,Lu,and Au) clusters

Discovering highly stable metal fullerenes such as the celebrated C 60 is interesting in cluster science as they have potential applications as building blocks in new nanostructures.We here investigated the structural and electronic properties of the fullerenes M 12 @Au 20（M=Na,Al,Ag,Sc,Y,La,Lu,and Au）,using a first-principles investigation with the density functional theory.It is found that these compound clusters possess a similar cage structure to the icosahedral Au 32 fullerene.La 12 @Au 20 is found to be particularly stable among these clusters.The binding energy of La 12 @Au 20 is 3.43 eV per atom,1.05 eV larger than that in Au 32.The highest occupied molecular orbital-lowest unoccupied molecular orbital（HOMO-LUMO） gap of La 12 @Au 20 is only 0.31 eV,suggesting that it should be relatively chemically reactive.

Hydrolysis Process of the Anticancer Agents Novel Non-classical trans-Platinum(Ⅱ) with Aliphatic Amines

The hydrolysis process of the anticancer agents novel non-classical transplatinum（ Ⅱ ） with aliphatic amines and the influence of solvent models therein have been studied by using hybrid density functional theory （B3LYP）. In this study, the stepwise hydrolysis, trans[PtCl2（Am）（isopropylamine）] ＋ 2H2O → trans-[Pt（Am）（isopropylamine）（OH2）2]^2＋＋ 2Cl^-, was explored. Implicit solvent effects were incorporated through polarized continuum models. The stationary points on the potential energy surfaces for the first and second hydrolysis steps,proceeding via a general SN2 pathway, were fully optimized and characterized. It was found that the first hydrolysis reaction is easier than the second one and the hydrolysis of trans- [PtCl2-（isopropylamine）2] is the easiest in our studying systems. The result can assist in under- tanding the hydrolysis mechanism of trans-[PtCl2（Am）（isopropylamine）] and designing novel Pt-based anticancer drugs.

A method for stochastic seismic response analysis of non-classically damped structures

A method to calculate the stationary random response of a non-classically damped structure is proposed that features clearly-defined physical meaning and simple expression. The method is developed in the frequency domain. The expression of the proposed method consists of three terms, i.e., modal velocity response, modal displacement response, and coupled (between modal velocity and modal displacement response). Numerical results from the parametric study and three example structures reveal that the modal velocity response term and the coupled term are important to structural response estimates only for a dynamic system with a tuned mass damper. In typical cases, the modal displacement term can provide response estimates with satisfactory accuracy by itself, so that the modal velocity term and coupled term may be ignored without loss of accuracy. This is used to simplify the response computation of non-classically damped structures. For the white noise excitation, three modal correlation coefficients in closed form are derived. To consider the modal velocity response term and the coupled term, a simplified approximation based on white noise excitation is developed for the case when the modal velocity response is important to the structural responses. Numerical results show that the approximate expression based on white noise excitation can provide structural responses with satisfactory accuracy.

Evaluation of Transient Absorption Spectra of N, N, N, N- Tetra - ( p -methylphenyl ) - 4, 4- diamino - 1, 1- diphenyl Ether ( TPDAE ) for Electron Transfer from TPDAE to Fullerenes ( C_(60) / C_(70) ) by Laser Flash Photolysis

Photoinduced electron transfer processes between fullerenes (C60 / C70) and N, N, N, N tetra - ( p-methylphenyl ) - 4, 4 diamino - 1, 1- diphenyl ether ( TPDAE ) have been studied by nanosecond laser flash photolysis. Quantum yields and rate constants of electron transfer from TPDAE to excited triplet state of fullerenes (C60 / C70 ) in benzonitrile have been evaluated by observing the transient absorption bands in the near-IR region where the excited triplet state, radical anion of fullerenes ( C60 / C70 ) and radical cations of TPDAE appear.

Mechanical properties of aluminum-based nanocomposite reinforced with fullerenes

The strengthening effect of fullerenes in aluminum matrix composites was investigated. The composites are produced using a two-step ball-milling technique combined with a hot rolling process. First, fullerene aggregates, where fullerene molecules initially come together to form giant particles(~200 μm in diameter) via van der Waals bonding, are shattered into smaller particles(~1 μm in diameter) by planetary milling. Second, primarily ball-milled fullerenes are dispersed in aluminum powder via attrition milling. Finally, aluminum/fullerene composite powder is consolidated by hot-rolling at 480 °C. For the composite sheet, grain refinement strengthening and dispersion hardening by fullerenes are accomplished at the same time, thereby exhibiting HV ~222 of Vickers hardness(e.g., ~740 MPa of yield strength) with only 2%(volume fraction) of fullerenes.

THE ANALYTICAL APPROACH FOR LARGE SCALE NON-CLASSICALLY DAMPED DYNAMIC SYSTEM

This paper gives a dynamic decoupling approach for the analysis of large scale non-classically damped system, in which the complex variable computations were completely avoided not only in solving for the eigenvalue problem but also in the calculation of the dynamic response. The analytical approaches for undamped gyroscopic system, non-classically damped system, including the damped gyroscopic system were unified. Very interesting and useful theoretical results, practical algorithms were obtained which are applicable to both non-defective and defective systems.

Concrete damage diagnosed using the non-classical nonlinear acoustic method

It is known that the strength of concrete is seriously affected by damage and cracking. In this paper, six concrete samples under different damage levels are studied. The experimental results show a linear dependence of the resonance frequency shift on strain amplitude at the fundamental frequency, and approximate quadratic dependence of the am- plitudes of the second and third harmonics on strain amplitude at the fundamental frequency as well. In addition, the amplitude of the third harmonics is shown to increase with the increase of damage level, which is even higher than that of the second harmonics in samples with higher damage levels. These are three properties of non-classical nonlinear acoustics. The nonlinear parameters increase from 106 to 108 with damage level, and are more sensitive to the damage level of the concrete than the linear parameters obtained by using traditional acoustics methods. So, this method based on non-classical nonlinear acoustics may provide a better means of non-destructive testing （NDT） of concrete and other porous materials.

Photon-added and photon-subtracted displaced Fock states and their non-classical properties

A new kind of quantum optical state, photon-added and -subtracted displaced Fock states, is introduced by applying the inverse of bosonic creation and annihilation operators to displaced Fock states. The quantum statistical properties of these states are investigated by numerical methods. Numerical results indicate that these states reveal some interesting non-classical properties, such as anti-bunching effects, sub-Poisson distributions and negativities of their Wigner functions.

Finite Element Processes Based on GM/WF in Non-Classical Solid Mechanics

In non-classical thermoelastic solids incorporating internal rotation and conjugate Cauchy moment tensor the mechanical deformation is reversible. This suggests that within the realm of linear mathematical models that only consider small strains and small deformation the mechanical deformation is reversible. Hence, it is possible to recast the conservation and balance laws along with constitutive theories in a form that adjoint A* of the differential operator A in mathematical model is same as the differential operator A. This holds regardless of whether we consider an initial value problem (IVP) (when the integrals over open boundary are neglected) or boundary value problem (BVP). Thus, in such cases Galerkin method with weak form (GM/WF) for BVPs and space-time Galerkin method with weak form (STGM/WF) for IVPs are highly meritorious due to the fact that: 1) the integral form for BVPs is variationally consistent (VC) and 2) the space-time integral forms for IVP are space time variationally consistent (STVC). The consequence of VC and STVC integral forms is that the resulting coefficient matrices are symmetric and positive definite ensuring unconditionally stable computational processes for both BVPs and IVPs. Other benefits of GM/WF and space-time GM/WF are simplicity of specifying boundary conditions and initial conditions, especially traction boundary conditions and initial conditions on curved boundaries due to self-equilibrating nature of the sum of secondary variables that only exist in GM/WF due to concomitant. In fact, zero traction conditions are automatically satisfied in GM/WF, hence need not be specified at all. While VC and STVC feature also exists in least squares process (LSP) and space-time least squares finite element processes (STLSP) for BVPs and IVPs, the ease of specifying traction boundary conditions feature in GM/WF and STGM/WF is highly meritorious compared to LSP and STLSP in which zero traction conditions need to be explicitly specified. A disadvantage of GM/WF and STGM/ WF is that the mathematical models (momentum equations) needed in the desired form contain higher order derivatives of displacements (upto fourth order), hence necessitate use of higher order spaces in their solution. As well known, this problem can be easily overcome in LSP and STLSP by introduction of auxiliary equations and auxiliary variables, thus keeping the highest orders of the derivatives of the dependent variables to one or any other desired order. A serious disadvantage of this approach in LSP is the significant increase in the number of dependent variables, hence poor computational efficiency. In this paper we consider non-classical continuum models for internally polar linear elastic solids in which internal rotations due to displacement gradient tensor (hence internal polar physics) are considered in the conservation and the balance laws and the constitutive theories. For simplicity, we only consider isothermal case;hence energy equation is not part of mathematical model. When using mathematical models derived in displacements in GM/WF and LSP in constructing integral forms, we note that in GM/WF the number of dependent variables is reduced drastically (only three in R3), whereas in case of first order systems used in LSP and STLSP we may have as many as 22 dependent variables for isothermal case. Thus, GM/WF results in dramatic improvement in computational efficiency as well as accuracy when minimally conforming spaces are used for approximations. In this paper we only consider mathematical model in R2 for BVPs (for simplicity). Mathematical models for IVP and BVP in R3 will be considered in subsequent paper. The integral form is derived in R2 using GM/WF. Numerical examples are presented using GM/WF and LSP to demonstrate advantages of finite element process derived using integral form based on GM/WF for non-classical linear theories for solids incorporating internal rotations due to displacement gradient tensor.

Ordered Rate Constitutive Theories for Non-Classical Thermoviscoelastic Fluids with Internal Rotation Rates

The paper presents constitutive theories for non-classical thermoviscoelastic fluids with dissipation and memory using a thermodynamic framework based on entirety of velocity gradient tensor. Thus, the conservation and the balance laws used in this work incorporate symmetric as well as antisymmetric part of the velocity gradient tensor. The constitutive theories derived here hold in coand contra-variant bases as well as in Jaumann rates and are derived using convected time derivatives of Green’s and Almansi strain tensors as well as the Cauchy stress tensor and its convected time derivatives in appropriate bases. The constitutive theories are presented in the absence as well as in the presence of the balance of moment of moments as balance law. It is shown that the dissipation mechanism and the fading memory in such fluids are due to stress rates as well as moment rates and their conjugates. The material coefficients are derived for the general forms of the constitutive theories based on integrity. Simplified linear (or quasi-linear) forms of the constitutive theories are also presented. Maxwell, Oldroyd-B and Giesekus constitutive models for non-classical thermoviscoelastic fluids are derived and are compared with those derived based on classical continuum mechanics. Both, compressible and incompressible thermoviscoelastic fluids are considered.