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1.
尽管目前人们对富勒烯[C60]的过渡金属有机物研究较多[1],但通过氮卡宾方式连接的C60二茂铁衍生物尚未见报道。鉴于对C60反应的浓厚兴趣及二茂铁的广泛应用价值[2]我们 利用C60的缺电子性[3]将其与二茂铁甲基氮卡宾进行[1+2]环加成反应,分离并表征了一种具有齿轮式结构的新奇C60二茂铁衍生物(CpFeC5H4CH2N)5C60(l)。 相似文献
2.
C60加成反应的理论研究 总被引:2,自引:1,他引:1
用AM1方法研究了C60与醌并二烯加成反应的机理,并对反应的过渡态及加成产物的构型进行了优化.研究发现,醌并二烯与C60的加成是协同进行的,反应的活化能较低;而氧取代的醌并二烯与C60的加成是协同进行但不同步,反应的活化能较高.前线轨道理论的研究表明反应是由亲二烯体C60的LUMO控制的. 相似文献
3.
制备了用于分离C60和C70的芘基丁酸改性锆-镁复合氧化物高效液相色谱固定相,并对其进行了表征;考察了流动相中甲苯含量、柱温和进样量对C60和C70分离的影响.结果表明,芘基丁酸改性锆-镁复合氧化物固定相对富勒烯有较强的保留,并对富勒烯表现出较强的分离能力,具有制备分离富勒烯的潜力. 相似文献
4.
二氧化碳(CO2)不仅仅是一种温室气体,更是一种重要的、有效的碳一资源,其来源丰富、无毒、无污染、不易燃烧,可用于生产有机化学品、材料、糖类等.由于CO2分子中的碳处于最高氧化态,且其分子具有热力学和动力学惰性,因此人们不断探索新型反应途径,以及新型的催化体系来有效资源化利用CO2.近年来,利用各种不饱和烃类,在过渡金属催化剂协助下催化CO2与烯烃生成不饱和羧酸及其衍生物引起了极大关注.其中,催化CO2/C2H4耦合反应制备丙烯酸及其衍生物因其原子经济性而备受瞩目.以镍系催化体系为主的过渡金属催化CO2/C2H4偶联反应是CO2化学转化与高值利用非常重要的研究热点之一.综述了近年来CO2/C2H4偶联反应的最新进展,对相应的催化反应机理进行了评述.从多个角度对各位学者的研究进行分析比... 相似文献
5.
对2~6个环的多环芳烃的氢提取反应类进行了系统研究, 提取氢原子的不饱和自由基包括丙炔基自由基(C3H3)、 烯丙基自由基(C3H5)、 丁二烯基自由基(nC4H5, iC4H5)、 环戊二烯基自由基(C5H5)以及苯基自由基(C6H5). 采用M06-2X/cc-pVTZ方法得到了多环芳烃的电子结构信息, 利用过渡态理论并结合Eckart隧道校正, 计算了所有反应在500~2500 K范围内的反应速率常数.考察了多环芳烃的大小、 结构对反应速率常数的影响, 对比了不同氢提取自由基及不同氢提取反应类型的速率常数. 结果表明, 多环芳烃的大小对反应速率常数影响不大, 但是多环芳烃的环结构对反应速率常数影响较大. 将不同的氢提取反应类简化为发生在五元环上的C5类和发生在六元环上的C6类两类, 结果表明, C6类的反应活性高于C5类. 研究了nC4H5, iC4H5以及C6H5自由基与多环芳烃的氢提取反应, 它们的氢提取反应活性大小顺序为C6H5>nC4H5>iC4H5. 通过对每类典型反应的速率常数取平均值, 总结出相应类型的速率规则, 可用于构建多环芳烃和碳烟机理. 相似文献
6.
用INDO系列方法对C602-与CH3反应的中间体C60(CH3)-进行理论研究,得到具有Cs对称性的构型。结果表明,CH3加成到C15上,将使与其相邻的双键碳(C30)的电荷密度和自旋密度达极大值,故加成反应部位在C30处;另外,C15的对位C12(或C27)也较其它部位易于反应,且有两个反应场所,因而产物C60(CH3)2可能为六元环上的1,2-加成和1,4-加成两种异构体的混合物。同时对两种加成产物的结构和电子光谱进行了理论研究,指认其电子跃迁,并讨论了其光谱红移的原因。 相似文献
7.
通过对介孔SBA-15孔壁氨基化(SBA-15-NH2),然后与C60反应形成化学键,成功地将C60组装进入SBA-15孔道中,合成了C60/SBA-15介孔复合材料.通过X射线衍射(XRD)、红外光谱(FTIR)、紫外-可见光谱(UV-V is)和差热-热重分析(TG-DTA)等方法对其进行了表征.同时,对复合材料的荧光性质进行了研究.结果发现,SBA-15-NH2在575 nm处出现发射峰,C60/SBA-15介孔复合材料在554 nm处出现发射峰,峰位蓝移21 nm. 相似文献
8.
异质富勒烯C58BN的结构与光谱研究 总被引:3,自引:0,他引:3
用AM1、MNDO和INDO半经验方法研究了异质富勒烯C58BN各异构体的结构、稳定性和电子光谱.所有这些半经验方法给出了相似的稳定性顺序.结果表明,在6-6位置取代的异构体是最稳定的,异构体的稳定性随杂原子间距离的增加而降低;与C60相比,硼氮杂富勒烯C58BN具有较低的前线轨道能级差、较小的电离势和较低的稳定化能.C58BN很可能具有与C60分子相似的反应活性,易发生亲核反应,但比C60更易失去电子形成正离子.以AM1优化构型为基础,利用INDO/CIS方法计算了各异构体的电子光谱. 相似文献
9.
C60O3的结构和电子光谱的理论研究 总被引:1,自引:1,他引:0
用INDO系列方法对C60O3的可能构型进行研究,结果表明:环氧结构邻近的6-6键易发生进一步的加成反应.其中3个氧原子加在同一个六元环的6-6边上,形成环氧结构最稳定的C3v构型,第3个氧原子加在2个环氧结构相邻的六元环的6-6边上的C2、Cs构型也相当稳定,C2、Cs构型的部分13C NMR谱与实验吻合.C60O3可能有较好的反应活性,其电子光谱属于理论预测. 相似文献
10.
利用自由基聚合反应合成了聚丙烯酸修饰的富勒烯(C60-PAA),进一步通过酯化反应将核黄素类似物6,7-二甲基-9-(2’-羟乙基)-异咯嗪(DHIX)与C60-PAA共价连接,得到C60-PAA-DHIX.利用傅立叶红外光谱(FT-IR)、核磁共振氢谱(1HNMR)、紫外-可见吸收光谱(UV-Vis)、荧光光谱对产物的化学结构进行了表征.循环伏安法表明,C60-PAA-DHIX中富勒烯基团的第一还原电位要高于DHIX基团的第一还原电位.ESR实验表明C60-PAA-DHIX能与N,N-二甲基苯胺发生多步光诱导电子转移反应,即DHIX基团与N,N-二甲基苯胺发生光诱导电子转移生成DHIX负离子自由基(DHIX-·),DHIX-·能进一步将电子传递给富勒烯生成富勒烯负离子自由基.DNA熔解曲线、紫外-可见吸收光谱和荧光光谱结果表明,C60-PAA-DHIX通过沟槽结合与CTDNA作用,而C60-PAA与DNA的作用较弱.无氧条件下,C60-PAA-DHIX具有比C60-PAA更强的DNA光损伤能力. 相似文献
11.
采用表面光电压和电场诱导表面光电压技术研究了三聚噻吩在外电场作用下的电子运动行为,结合三聚噻吩的UV光谱、极化子概念以及前线轨道理论,指认了三聚噻吩能级跃迁性质,即380nm附近的峰为带-带跃迁峰,477,465和600nm附近的峰是与单极化子有关的电子跃迁;而在770和990nm附近的峰则是与双极化子有关的电子跃迁峰。 相似文献
12.
The growth of Au clusters on a fullerene thin film was investigated by in situ photoelectron spectroscopy in the ultraviolet (UPS) and x-ray (XPS) regime. Due to its highly corrugated surface fullerene films provide a wide range of bonding sites which could be exploited as molecular templates and serve to create a cluster superstructure. To gain insight into the fullerene-Au interaction two types of experiments were performed: (i) the deposition of Au on a fullerene surface, and (ii) the deposition of fullerenes on a Au surface. In both experiments an island growth mode is observed. The deposition of submonolayer amounts of C60 onto a gold film showed that the main interaction of the two species is due to chemisorption of the first C60 monolayer. In addition a constant band bending in the fullerene film is detected, but the UPS valence-band spectra show that there is no charge transfer from the Au to the C60 lowest unoccupied molecular orbital. In the reverse experiment, the cluster growth of Au on the corrugated C60 surface, the analysis of the Au core level does not reveal a specific bonding or nucleation site for Au atoms and clusters. This is in contrast to observations with Si clusters, which prefer to reside in the troughs between the fullerene molecules. The Au clusters grow continually from a size of about 55 atoms for the early stages of growth up to 150 atoms for the deposition of a nominal coverage of 1.5 nm. These data are derived from an analysis of the d-band splitting and the Au 4f core-level shift due to delayed photohole relaxation. The thermal stability of the Au-clusters-covered fullerene film was investigated by annealing in situ up to temperatures of 650 degrees C. For temperatures up to 450 degrees C a continuous growth of the clusters is detected, which is accompanied by a slight drop in Au concentration in the range of XPS for annealing temperatures higher than 350 degrees C. This may be due to a ripening of the clusters. The presence of Au apparently delays fullerene sublimation. The film shows a very good thermal stability and even after annealing at 650 degrees C there is still a fullerene film detectable in the photoelectron spectroscopy spectra. 相似文献
13.
Hatano T Bae AH Sugiyasu K Fujita N Takeuchi M Ikeda A Shinkai S 《Organic & biomolecular chemistry》2003,1(13):2343-2347
It was found that [60]fullerene encapsulated in p-sulfonatocalix[8]arene and single-walled carbon nanotubes (SWNTs) solubilized by sodium dodecylsulfate can be readily deposited on the ITO electrode by electrochemical oxidative polymerization of ethylenedioxythiophene (EDOT) without chemical modification of these carbon clusters. The driving force for the deposition is an electrostatic interaction between the anionic complexes and the cationic charges of poly(EDOT) formed in the oxidative polymerization process. The surface morphology was thoroughly characterized by scanning electron micrograph: the [60]fullerene/poly(EDOT) film is covered by nano-particles with 20-100 nm diameters whereas the SWNTs/poly(EDOT) film is covered by nanorods with several microm length and ca. 100 nm diameter. The results indicate that the anionic complexes act as nuclei for the polymer growth in the oxidation polymerization. Interestingly, when these modified ITO electrodes were photoirradiated, the appearance of a photocurrent wave was observed. The action spectra showed that the photoexcited energy of [60]fullerene or SWNTs is efficiently collected by the electroconductive poly(EDOT) film and transferred to the ITO electrode. 相似文献
14.
Arenst Andreas Arie Wonyoung Chang Joong Kee Lee 《Journal of Solid State Electrochemistry》2010,14(1):51-56
To improve the electrochemical performances of Si thin film anodes for lithium rechargeable batteries, fullerene thin films
are prepared by plasma-assisted evaporation methods to be used as coating materials. Analyses via Raman and X-ray photoelectron
spectroscopy indicate that amorphous polymeric films originated from fullerene are formed on the surface of the silicon thin
film. The electrochemical performance of these fullerene-coated silicon thin film as an anode material for rechargeable lithium
batteries has been investigated by cyclic voltammetry, charge/discharge tests, and electrochemical impedance spectroscopy.
The fullerene-coated Si thin films demonstrated a high specific capacity of above 3,000 mAh g−1 as well as good capacity retention for 40 cycles. In comparison with bare silicon anodes, the fullerene-coated silicon thin
film showed superior and stable cycle performance which can be attributed to the fullerene coating layer which enhances the
Li-ion kinetic property at the electrode/electrolyte interface. 相似文献
15.
《Journal of Polymer Science.Polymer Physics》2018,56(15):1094-1100
Optical properties of polymer/fullerene blend films upon thermal annealing are investigated by spectroscopic ellipsometry and described consistently within an optical model of the blend film. The optical model developed in this work treats both components, polymer and fullerene, as mixtures of reference materials, that is, their optically ordered and disordered phase. Then, the polymer/fullerene blend layer is also described as a mixture of these two components. In this manner, we extend an existing optical model, which accounts for the optical order within the polymer phases, on cases where the optically ordered PCBM phase occurs, too. Determination of the dielectric functions of all four reference materials allows for a unique quantitative characterization of a polymer/fullerene blend film by assigning to it thickness and the polymer to fullerene volume fraction of its layers as well as corresponding volume fractions of theirs optically ordered and disordered polymer and fullerene phases. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1094–1100 相似文献
16.
Fluoroalkyl end‐capped oligomers were solubilized into a variety of ionic liquids such as N‐methylpyrazolium tetrafluoroborate, 3‐methylpyrazolium tetrafluoroborate and 1‐butyl‐3‐methylimidazolium hexafluorophosphate, and these fluorinated oligomers were able to reduce the surface tension of these ionic liquids. Interestingly, these fluorinated oligomers were able to solubilize fullerene into ionic liquids effectively. Fluoroalkyl end‐capped fullerene co‐oligomers, which were prepared by the oligomerizations of fluoroalkanoyl peroxides with radical polymerizable monomers such as acryloylmorpholine in the presence of fullerene, were more effective in solubilizing fullerene into ionic liquids compared to the corresponding fluoroalkyl end‐capped homo‐oligomers possessing no fullerene units. Fluoroalkyl end‐capped fullerene co‐oligomers/fullerene/ionic liquid complexes thus obtained were applied to the arrangements of fullerenes above the poly(methyl methacrylate) (PMMA) surface, and the higher fluorescent intensity of fullerene was obtained in the modified PMMA surface, although the reverse side of this modified film surface afforded an extremely weak fluorescent intensity. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
17.
Ginzburg B. M. Shibaev L. A. Kireenko O. F. Shepelevskii A. A. Baidakova M. V. Sitnikova A. A. 《Russian Journal of Applied Chemistry》2002,75(8):1330-1335
The protective film (1000 Å thick) formed on the copper foil surface upon friction of a steel roller lubricated with industrial oil containing 5% fullerene C6
0 was studied by optical and electron microscopy, X-ray diffraction (XRD) analysis, hardness measurements, and mass spectrometry. This protective film is probably a fullerene-polymer network formed by fullerene C6
0 and covalently bound fragments of hydrocarbon chains released in the course of mechanochemical degradation of the lubricating oil. The film exhibits elevated hardness and antiwear properties, and increases the load-carrying power of the tribotechnical unit. Chemical mechanisms of tribopolymerization were analyzed. 相似文献
18.
Emilia Grodzka Joanna Grabowska Monika Wysocka-Żołopa Krzysztof Winkler 《Journal of Solid State Electrochemistry》2008,12(10):1267-1278
The electrochemically active polymers have been formed during electro-reduction carried out in solution containing fullerenes,
C60 or C70, and transition metal complexes of Pd(II), Pt(II), Rh(III), and Ir(I). In these films, fullerene moieties are covalently
bounded to transition metal atoms (Pd and Pt) or their complexes (Rh and Ir) to form a polymeric network. All films exhibit
electrochemical activity at negative potentials due to the fullerene cages reduction process. For all studied metal complexes,
yields of formation of films containing C70 are higher than yields of electrodeposition of their C60 analogs. C70
/M films also exhibit higher porosity in comparison to C60/M layers. The differences in film morphology and efficiency of polymer formation are responsible for differences in electrochemical
responses of these films in acetonitrile containing supporting electrolyte only. C70/M films shows more reversible voltammeric behavior in negative potential range. They also show higher potential range of electrochemical
stability. Processes of film formation and electrochemical properties of polymers depend on the transition metal ions or atoms
bonding fullerene cages into polymeric network. The highest efficiency of polymerization was observed for fullerene/Pd and
fullerene/Rh films. In the case of fullerene/Pd films, the charge transfer processes related to the fullerene moieties reduction
in negative potential range exhibit the best reversibility among all of the studied systems. Capacitance performances of C60/Pd and C70/Pd films deposited on the porous Au/quartz electrode were also compared. Capacitance properties of both films are significantly
affected by the conditions of electropolymerization. Only a fraction of the film having a direct contact with solution contributes
to pseudocapacitance. Capacitance properties of these films also depend on the size of cations of supporting electrolyte.
The C70/Pd film exhibits much better capacitance performance comparison to C60/Pd polymer. 相似文献
19.
Stupavska M Jerigova M Michalka M Hasko D Szoecs V Velic D 《Journal of the American Society for Mass Spectrometry》2011,22(12):2179-2187
A technique for improving the sensitivity of high mass molecular analysis is described. Three carbon species, fullerenes,
single walled carbon nanotubes, and highly ordered pyrolytic graphite are introduced as matrices for the secondary ion mass
spectrometry analysis of cyclodextrin (C42H70O35, 1134 u). The fullerene and nanotubes are deposited as single deposition, and 10, 20, or 30 deposition films and cyclodextrin
is deposited on top. The cyclodextrin parent-like ions and two fragments were analyzed. A 30 deposition fullerene film enhanced
the intensity of cationized cyclodextrin with Na by a factor of 37. While the C6H11O5 fragment, corresponding to one glucopyranose unit, increased by a factor of 16. Although fragmentation on fullerene is not
suppressed, the intensity is twice as low as the parent-like ion. Deprotonated cyclodextrin increases by 100× and its C8H7O fragment by 10×. While the fullerene matrix enhances secondary ion emission, the nanotubes matrix film generates a basically
constant yield. Graphite gives rise to lower intensity peaks than either fullerene or nanotubes. Scanning electron microscopy
and atomic force microscopy provide images of the fullerene and nanotubes deposition films revealing flat and web structured
surfaces, respectively. A “colliding ball” model is presented to provide a plausible physical mechanism of parent-like ion
enhancement using the fullerene matrix. 相似文献
20.
《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1467-1487
Abstract The fixation of film morphology is essential for the long‐term stability of heterojunction polymer photovoltaic (PV) cells. An epoxy‐functionalized fullerene C60 derivative was synthesized for this purpose. This material can be polymerized at acidic conditions and was found to stabilize the phase‐separated morphologies within blended polythiophene–fullerene heterojunction films. The phase stability of the films was characterized by UV‐VIS spectroscopy and optical microscope. Crosslinkable polythiophene derivatives were also prepared but these materials were much less effective in stabilizing film morphology when mixed into PCBM (C61‐butyric acid methyl ester). Heterojunction polymer PV cells were prepared from these materials and their performance was compared with cells made from conventional materials. 相似文献