Photoconductivity of [60]fullerene derivatives

Two [60]fullerene derivatives (compounds 1 and 2) have been synthesized. Their redox properties have been measured by cyclic voltammetry. The photoconductivities of poly(N-vinylcarbazole) (PVK) doped with [60] fullerene and with their derivatives have been studied to explore the possible relationship between the reductibility of fullerenes and the photoconductivity of fullerenes-doped PVK. The charge generation efficiencies of PVK doped with [60]fullerene and with its derivatives have changed remarkably: the diversity of charge generation efficiency is obvious in different doping systems. The result indicates that there is charge transfer between fullerenes and PVK.     

Controlled fabrication of fullerene derivative one-dimensional nanostructures via electrophoretic deposition of its clusters

Well-defined and controllable one-dimensional(ID) nanostructures of fullerene derivative have been prepared by an electrophoretic template synthesis method. The clusters of fullerene derivative formed in mixed solvents are introduced into the channels of porous alumina templates through a dc electric field. Four types of ID nanostructures(solid nanowires, solid-wall nanotubes, porous nanowires and porous-wall nanotubes) have been obtained by changing the deposition parameters. This,approach opens a new avenue to assemble fullerene derivatives, endohedral fullerenes, as well as other functional organic compounds, which can form clusters in ID nanostructure arrays for applications in chemical sensors, light energy conversion devices and nanoscale electronic and optoelectronic devices.     

Fullerenes from aromatic precursors by surface-catalysed cyclodehydrogenation

Graphite vaporization provides an uncontrolled yet efficient means of producing fullerene molecules. However, some fullerene derivatives or unusual fullerene species might only be accessible through rational and controlled synthesis methods. Recently, such an approach has been used to produce isolable amounts of the fullerene C(60) from commercially available starting materials. But the overall process required 11 steps to generate a suitable polycyclic aromatic precursor molecule, which was then dehydrogenated in the gas phase with a yield of only about one per cent. Here we report the formation of C(60) and the triazafullerene C(57)N(3) from aromatic precursors using a highly efficient surface-catalysed cyclodehydrogenation process. We find that after deposition onto a platinum (111) surface and heating to 750 K, the precursors are transformed into the corresponding fullerene and triazafullerene molecules with about 100 per cent yield. We expect that this approach will allow the production of a range of other fullerenes and heterofullerenes, once suitable precursors are available. Also, if the process is carried out in an atmosphere containing guest species, it might even allow the encapsulation of atoms or small molecules to form endohedral fullerenes.     

掺杂C60的聚乙烯基咔唑光导光膜的光电子能谱

采用Ｘ－射线光电子能谱表面分析技术并通过变温手段研究了聚乙烯基咔唑（ＰＶＫ）与Ｃ６０的作用形态，结果表明，ＰＶＫ与Ｃ６０可以形成电荷转移络合物，并且它的形成和解离随着温度的变化是可逆的。ＰＶＫ与Ｃ６０的电荷转移络合物的形成可能是改善ＰＶＫ光电性能的关键所在。     

Superconductivity in single crystals of the fullerene C70.

The observation of superconductivity in doped C60 has attracted much attention, as these materials represent an entirely new class of superconductors. A maximum transition temperature (Tc) of 40 K has been reported for electron-doped C60 crystals, while a Tc of 52 K has been seen in hole-doped crystals; only the copper oxide superconductors have higher transition temperatures. The results for C60 raise the intriguing questions of whether conventional electron-phonon coupling alone can produce such high transition temperatures, and whether even higher transition temperatures might be observed in other fullerenes. There have, however, been no confirmed reports of superconductivity in other fullerenes, though it has recently been observed in carbon nanotubes. Here we report the observation of superconductivity in single crystals of electric-field-doped C70. The maximum transition temperature of about 7 K is achieved when the sample is doped to approximately four electrons per C70 molecule, which corresponds to a half-filled conduction band. We anticipate superconductivity in smaller fullerenes at temperatures even higher than in C60 if the right charge density can be induced.     

富勒烯科学的若干研究进展

富勒烯的三维空间构型和众多的双键为富勒烯科学的发展提供了广阔的空间，内嵌富勒烯则可以通过控制笼内包合的原子来调节富勒烯的电子结构和还原性质。目前，富勒烯的研究主要集中在富勒烯和金属富勒烯基新型功能材料的合成表征以及应用，其中以设计新的富勒烯／金属富勒烯材料用于化学传感器、太阳能电池及其它器件为主要研究焦点。旨在对目前富勒烯科学的发展与应用研究作一综述介绍。     

掺杂聚合物对有机电致发光二极管的影响

利用甩胶方法在导电玻璃上分别制得单一的聚烷基噻吩并在其中掺杂不同量的聚乙烯咔唑的有机发光层，再用真空蒸发方法将铝沉积在这些有机层上作为发光二极管的负极。选择合适的掺杂比，电致发光二极管在电压为５Ｖ、电流密度为３０ｍＡ／ｃｍ＾２时就有光输出。这一结果表明，掺杂具有空穴特性的聚乙烯咔唑对增强短烷基侧链的聚烷基噻吩电致发光强度是一种有效的方法。     

Solvothermal synthesis of CdS nanorods and photovoltaic characteristics of CdS/PVK composite system

Large quantities of CdS nanorods are successfully synthesized through Cd（CH3COO）2·2H2o reacting with Na2S·9H2O and EDA in aqueous solution. XRD result shows that the sample is of hexagonal structure. And TEM result shows that the morphologies of the resulting CdS are mainly in three-armed rod-like structure with a diameter of 10--15 nm and a length of 100 nm. The nanocomposites of CdS/PVK with different molar ratios are prepared by spin coating method on tin-doped indium oxide （ITO） substrate. A notable decrease of photoluminescence （PL） efficiency and a significant enhancement of surface photovoltage signal have been observed in CdS/PVK composites when the molar fraction of CdS increases. We interpret these results as the energy level matching between CdS and PVK in nanocomposites. This energy level matching facilitates fast interfacial charge transfer then increases the separation efficiency of electron-hole pairs and the carrier generation efficiency. The detailed charge transfer process has also been demonstrated.     

富勒烯新结构的研究进展

富勒烯Cn是一类由12个五元环和若干六元环组成的笼状全碳分子.根据碳笼表面是否含相邻分布的五元环,富勒烯可分为IPR富勒烯和非IPR富勒烯.25年来,人们在发展富勒烯合成新方法和寻找富勒烯新结构方面做了大量的工作,富勒烯家族得到了很大的扩充,越来越多的富勒烯新结构被陆续发现和分离出来.迄今为止,已分离、表征了C20~C104的60余种富勒烯新结构,包括40余种IPR富勒烯结构,以及通过笼外化学修饰或内嵌原子(或原子簇)的稳定化策略合成的20余种违反IPR规则的富勒烯.详细总结了这些迄今为止已报道的各种富勒烯新结构,并对今后富勒烯研究的重点和内容进行了预测.     

煤基富勒烯的制备研究

以 1 4种国产煤为原料 ,用电弧等离子体蒸发法制备富勒烯 .富勒烯产品的表征采用质谱、紫外光谱、红外光谱及高压液相色谱技术 .考察了煤样的基础性质对富勒烯产率的影响 .结果表明 ,由实验所用煤种均可制得富勒烯 ;原料煤本身的化学结构和组成影响富勒烯的产率和分布 ;由某些煤得到的富勒烯中 ,C70 的含量较之以石墨电极为原料时的含量要高得多 .     

硼富勒烯及其相关结构研究进展

本文对硼富勒烯等硼纳米结构及其相关材料的研究进展进行了简要评述. 首先对硼和碳元素及其成键性质的区别与联系进行了讨论, 并简要介绍了碳富勒烯、纳米管和石墨烯的发现及其结构与性质. 接下来系统回顾了过去几十年来人们对硼团簇、硼纳米管和硼纳米线等纳米结构在理论和实验研究方面取得的进展.特别是最近几年来, 针对硼富勒烯、硼纳米管、硼单层平面、硼富勒烯固体等结构的研究取得了一些重要进展, 本文在结合我们自己研究工作的基础上, 对上述研究进展做了系统地介绍. 最后对硼富勒烯及其相关材料的研究前景进行了展望.     

掺杂B4C对电弧法制备的富勒烯的影响

以高纯石墨棒为阴极,以掺有Ｂ４Ｃ的石墨棒为阳极,用直流电弧法制备富勒烯,对掺杂Ｂ４Ｃ对富勒烯的影响进行了研究。结果表明：（１）掺杂Ｂ４Ｃ使富勒烯的总产率显著下降,且Ｂ４Ｃ的量越大,总产率越低;（２）当孔中掺入Ｂ４Ｃ与石墨的混合物时,产物为纯碳富勒烯,其中大分子富勒烯的相对含量较不掺杂时显著提高;当孔中掺入纯Ｂ４Ｃ时,生成的富勒烯中含有骨架掺硼富勒烯。     

掺杂C60的PVK及其共聚物的光电导性能

通过自由基共聚合的方法制备了一系列乙烯基咔唑／丙烯酸丁酯（ＮＶＣ／ＢＡ）的共聚物,发现ＮＶＣ能和ＢＡ进行较好的共聚合反就投料比和共聚产物中的各单元组成比接近。通过ＴＥＭ观察。加入的共聚单体ＢＡ可以大大改善了聚乙烯基咔唑（ＰＶＫ）的成膜性能。也对掺有Ｃ６０的ＰＶＫ的均聚和共取物的光电导性能进行了研究。实验结果表明Ｃ５０的加入可以大大增进ＰＶＫ的光电导性能,并且随着Ｃ６０的增加光电导性能增强;共聚体系     

掺杂碳化钨对电弧法制备的富勒烯的影响

以掺碳化钨的石墨棒为阳级，以高纯石墨棒为阴极，用直流电弧法合成富勒烯，并对碳化钨对富勒 烯的影响进行了研究。     

低聚噻吩/富勒烯混合液中分子大小相关的电子转移效率(英文)

为了洞悉有机太阳能电池中的光致电子转移机制,利用荧光光谱方法研究低聚噻吩(分别包含2个,4个和6个噻吩)与富勒烯(碳60,70和碳84)混合液中的荧光猝灭.研究结果表明低聚噻吩/富勒烯混合液中的电子转移效率依赖于低聚噻吩的链长及富勒烯的电子亲和力,并与基于Weller方程计算获得的结果是一致的.     

Inhibition of M-MuLV reverse transcriptase activity by fullerene derivatives

The biological properties and biomedical application of fullerene (C60) and its derivatives are currently very active subjects concerning fullerene research. The bio logical effects of fullerene and its derivatives include enzyme inhibition, sites-selective DNA cleavage, antibacterial and antiviral activities, photocytotoxicity and antiapoptosis[1―4]. Especially, enzymes inhibited by fullerene derivatives mainly consist of oxidation-reduc- tion related enzymes such as glutathione transferase…     

富勒烯[ 60] 与电子给体电荷转移络合物的特性

通过毫微秒激光光解作用研究了富勒烯[60]电荷转移络合物的特性，在苯腈溶液中，从电子给体(TTF)到富勒烯[60]激发三线态的电子转移反应已被观察到，富勒烯[60]激发三线态的消失和富勒烯[60]阴离子自由基的出现，通过瞬态吸收光谱得到证实。     

富勒烯(C60/C70)与 N,N,N′,N′-四-(对甲基苯)-4,4′-二胺-1,1′-二苯碲醚电荷转移复合物的特征

用激光光解方法研究了富勒烯(C60 / C70)与N,N,N′,N′-四-(对甲基苯)-4,4′-二胺-1,1′-二苯碲醚电荷转移复合物的特征. 通过观察在近红外区瞬间吸收带,富勒烯(C60 / C70)激发三线态,富勒烯(C60 / C70)阴离子自由基和N,N,N′,N′-四-(对甲基苯)-4,4′-二胺-1,1′-二苯碲醚阳离子自由基的出现,测定了在苯腈溶液中从N,N,N′,N′-四-(对甲基苯)-4,4′-二胺-1,1′-二苯碲醚到富勒烯(C60 / C70)激发三线态的量子转化产率和电子转移常数.     

富勒烯[4,6]-(C24)n(n=1,2,4,8)及相应的BN团簇的理论研究

用AM1半经验量子化学方法,对富勒烯[4,6]-(C₂₄)_n(n=1,2,4,8)及相应的BN完全取代物进行几何构型优化和频率分析.计算结果表明,BN团簇及相应的全碳富勒烯的稳定性均随对称性的变化而呈现相似的递变规律;BN取代增强了体系的稳定性,使得BN团簇有望在实验室中得到;各分子的净电荷分布为实验室寻找分子反应的活性部位提供了理论依据.[     

Pure and stable white organic light-emitting device with an ultra-thin layer

Due to high brightness, low viewing angle, low driving voltage and short response time, organic light-emitting display is appraised as one of the most promising flat displays in the near future. Full-color technology is the bottle neck for industrializati…