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排序方式: 共有454条查询结果,搜索用时 46 毫秒
61.
用含金属氧化物的石墨棒作电极 ,在氩气氛中利用弧放电制备碳纳米类物质。用于分析测定的物质是碳纳米类物质 C6 0 、C70 、C76 、C78、C84 以及 La@C82 ,得到其在正离子状态下的分子离子及碎片离子。碳纳米类分子以 C2 -碎片丢失的方式进行特征解离。对不同碳纳米物质的系列碎片峰的强度进行研究结果表明 :碎片[M-C2 n H]+丰度随球形分子的体积的增大而增加 ,而且碎片 [M-C2 n H]+的丰度略大于 [M-C2 n]+。激光飞行时间质谱分析为碳纳米分子结构及其稳定性提供了十分有用的信息 相似文献
62.
Jaehyun Park Se Hun Joo Yoon‐Jeong Kim Ju Hyun Park Sang Kyu Kwak Seokhoon Ahn Seok Ju Kang 《Advanced functional materials》2019,29(32)
In this work, a highly conductive organic cocrystal is investigated as an anode material for conducting agent‐free lithium‐ion battery (LIB) electrodes. A unique morphology of semiconducting fullerene (C60) and contorted hexabenzocoronene (cHBC) is developed as a cocrystal that efficiently enhances the electron transfer during discharge and charge processes due to the formation of a well‐defined junction between C60 and cHBC. In particular, the present study reveals the exact cocrystal phase of orthorhombic Pnnm using grazing incidence X‐ray diffraction characterization and computational methods. The detailed cocrystal structure analysis indicates that the columnar structure of C60/cHBC cocrystal facilitates the reliable vacant sites for Li+ storage, which ultimately enhances the reversible capacity to 330 mAh g–1 at 0.1 A g–1 with long cyclability of 600 cycles in the absence of a conducting agent. Furthermore, the rate performance of the C60/cHBC cocrystal anode is improved compared to that of the graphite anode, indicating that the cocrystal formation between C60 and cHBC enhances the charge transport at a high current density. It demonstrates that the approach of this study can be a promising strategy for preparing conducting agent‐free organic cocrystal anodes, which also provides a viable design rule for high‐performance LIBs electrodes. 相似文献
63.
Shaoqing Zhang Yunpeng Qin Jie Zhu Jianhui Hou 《Advanced materials (Deerfield Beach, Fla.)》2018,30(20)
Fluorine‐contained polymers, which have been widely used in highly efficient polymer solar cells (PSCs), are rather costly due to their complicated synthesis and low yields in the preparation of components. Here, the feasibility of replacing the critical fluorine substituents in high‐performance photovoltaic polymer donors with chlorine is demonstrated, and two polymeric donors, PBDB‐T‐2F and PBDB‐T‐2Cl, are synthesized and compared in parallel. The synthesis of PBDB‐T‐2Cl is much simpler than that of PBDB‐T‐2F. The two polymers have very similar optoelectronic and morphological properties, except the chlorinated polymer possess lower molecular energy levels than the fluorinated one. As a result, the PBDB‐T‐2Cl‐based PSCs exhibit higher open circuit voltage (Voc) than the PBDB‐T‐2F‐based devices, leading to an outstanding power conversion efficiency of over 14%. This work establishes a more economical design paradigm of replacing fluorine with chlorine for preparing highly efficient polymer donors. 相似文献
64.
Ternary System with Controlled Structure: A New Strategy toward Efficient Organic Photovoltaics 下载免费PDF全文
Pei Cheng Rui Wang Jingshuai Zhu Wenchao Huang Sheng‐Yung Chang Lei Meng Pengyu Sun Hao‐Wen Cheng Meng Qin Chenhui Zhu Xiaowei Zhan Yang Yang 《Advanced materials (Deerfield Beach, Fla.)》2018,30(8)
Recently, a new type of active layer with a ternary system has been developed to further enhance the performance of binary system organic photovoltaics (OPV). In the ternary OPV, almost all active layers are formed by simple ternary blend in solution, which eventually leads to the disordered bulk heterojunction (BHJ) structure after a spin‐coating process. There are two main restrictions in this disordered BHJ structure to obtain higher performance OPV. One is the isolated second donor or acceptor domains. The other is the invalid metal–semiconductor contact. Herein, the concept and design of donor/acceptor/acceptor ternary OPV with more controlled structure (C‐ternary) is reported. The C‐ternary OPV is fabricated by a sequential solution process, in which the second acceptor and donor/acceptor binary blend are sequentially spin‐coated. After the device optimization, the power conversion efficiencies (PCEs) of all OPV with C‐ternary are enhanced by 14–21% relative to those with the simple ternary blend; the best PCEs are 10.7 and 11.0% for fullerene‐based and fullerene‐free solar cells, respectively. Moreover, the averaged PCE value of 10.4% for fullerene‐free solar cell measured in this study is in great agreement with the certified one of 10.32% obtained from Newport Corporation. 相似文献
65.
Incorporating Pyrrolic and Pyridinic Nitrogen into a Porous Carbon made from C60 Molecules to Obtain Superior Energy Storage 下载免费PDF全文
66.
Takanori Kobayashi Keiichi Yokoyama 《Journal of Nuclear Science and Technology》2016,53(10):1489-1493
Theoretical investigation for the adsorption of the cesium atom (Cs), the cesium iodide molecule (CsI), the iodine atom (I), the cesium cation (Cs+), and the iodide anion (I?) onto the surface of a single fullerene molecule (C60) are reported. A hybrid exchange–correlation functional using the Coulomb-attenuating method (CAM-B3LYP) is employed. The adsorption energies, i.e., the opposite of enthalpy change through adsorption, are calculated to be 143, 12, 9, 46, and 49 kJ mol?1 for Cs, CsI, I, Cs+, and I?, respectively. The equilibrium constant for Cs is calculated to be 7×103 atm?1 at the temperature of 1000 K and is seven orders of magnitude higher than that for CsI, indicating that the C60 molecule adsorb the Cs atom highly selectively against the CsI molecule. 相似文献
67.
本文介绍了用交流碳弧法制备富勒烯材料的工艺。对材料的紫外光谱和红外光谱进行了测量和分析,讨论了氦气压以及电流电压对材料产率的影响,指出氦气压在24×103~33×103Pa之间,电流100A,电压18V时,C60的产率较高。 相似文献
68.
69.
Marcella Bonchio Mauro Carraro Gianfranco Scorrano Alessandro Bagno 《Advanced Synthesis \u0026amp; Catalysis》2004,346(6):648-654
Hybrid compounds consisting of an organic sensitizer and a polyoxometalate unit were synthesized following two strategies: a) the covalent functionalization of lacunary decatungstosilicate with organosilylfulleropyrrolidines; b) the charge interaction between cationic sensitizers and the polyoxoanions, yielding electrostatic aggregates. These hybrid complexes effect catalytic photooxygenation in water under heterogeneous conditions, 25 °C and O2 (1 atm), using visible light irradiation (λ>375 nm). As representative target substrates, phenol (4 mM) is oxidized in 150 min with a COD loss up to 30% (TON up to 50), while L ‐methionine methyl ester (15 mM) undergoes selective photooxygenation to the corresponding sulfoxide in 90 min (TON up to 200). The photocatalyst stability has been evaluated on the basis of system recycling along three oxidation runs. The inhibition exerted by sodium azide, a typical 1O2 quencher, suggests the occurrence of a Type II photooxidation mechanism. 相似文献
70.
采用分子动力学(MD)与量子力学(QM)相结合的方法,模拟了Cn(n=20、60、80、180)富勒稀分子,以及M@C60(M=Na、Fe、Al)内嵌金属原子富勒稀分子的对径压缩过程,获得了各种富勒稀分子的系统能量-变形曲线、载荷-变形曲线、最大承受载荷、失效应变以及压缩刚度等压缩力学性能数据.根据模拟的结果,分析了具有不同幻数n、不同内嵌金属原子的富勒稀分子压缩力学特性的差异.研究表明,碳富勒稀分子具有出色的压缩力学性能;幻数n较大的富勒稀分子的最大承受载荷和压缩刚度较大,但失效应变较小;与未填充碳富勒稀分子相比,内嵌金属原子富勒稀分子具有更好的承载能力. 相似文献