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31.
本文以低比例的磷光材料作为给体,制备了基于MoOx/C60:x%Ir(ppy)3的有机太阳能电池(OPV)器件.其中,C60为高比例的受体材料,金属配合物Ir(ppy)3为低比例的给体材料,MoOx为阳极缓冲层.通过一系列不同Ir(ppy)3比例的OPV器件对比研究,得出了最优器件结构.研究发现,当Ir(ppy)3比例足够小时,器件表现为肖特基势垒,开路电压(VOC)较大,短路电流(JSC)较小;随着Ir(ppy)3比例的增加,VOC逐渐减少,而JSC逐渐增大;当进一步增加Ir(ppy)3比例时,VOC趋于稳定,JSC开始减小.结果显示,5%Ir(ppy)3比例的器件性能最佳,效率达1.7%.为了使器件效率得到进一步提升,本研究组采用吸收光谱范围比C60更宽的C70作为受体材料,使光电转换效率进一步提升至3.0%. 相似文献
32.
33.
Inese Sarcevica Liana Orola Mikelis V. Veidis Sergey Belyakov 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(4):392-395
A new polymorph of the cinnamic acid–isoniazid cocrystal has been prepared by slow evaporation, namely cinnamic acid–pyridine‐4‐carbohydrazide (1/1), C9H8O2·C6H7N3O. The crystal structure is characterized by a hydrogen‐bonded tetrameric arrangement of two molecules of isoniazid and two of cinnamic acid. Possible modification of the hydrogen bonding was investigated by changing the hydrazide group of isoniazid via an in situ reaction with acetone and cocrystallization with cinnamic acid. In the structure of cinnamic acid–N′‐(propan‐2‐ylidene)isonicotinohydrazide (1/1), C9H8O2·C9H11N3O, carboxylic acid–pyridine O—H...N and hydrazide–hydrazide N—H...O hydrogen bonds are formed. 相似文献
34.
利用B3LYP/6-311+G(2d,p)方法对一种新型含能增塑剂双(2,2-二硝基丙基)甲缩醛进行几何优化,计算了其红外光谱、生成焓和爆轰特性. 分析了最弱键的键离解能和键级并预测了目标化合物的热稳定性. 结果表明双(2,2-二硝基丙基)甲缩醛中的四个N-NO2键的键离解能都为164.38 kJ/mol. 表明目标化合物是一个热力学性能稳定的化合物. 以凝聚相生成焓和分子密度为基础,采用Kamlet-Jacobs方法预测其爆速和爆压. 目标化合物的晶体结构属于P21空间群. 相似文献
35.
20世纪60年代,美国密执安州立大学Rosenberg发现了顺铂具有抗癌活性,开辟了金属类抗肿瘤药物研究的新领域.经过40余年的研究,已相继成功开发了卡铂、奈达铂、奥沙利铂、舒铂、洛铂和双环铂等铂类抗肿瘤药物.虽然对于铂类抗肿瘤药物研究取得了一定的成绩,但在临床使用过程中也存在一些问题,如其毒副作用和抗药性,限制了其在临床上的进一步广泛应用.为了解决这些问题,科研工作者开始寻找新的金属类抗肿瘤药物以弥补现有铂类抗肿瘤药物的不足.在金属元素中,唯有钯(II)与铂(II)配合物具有相似或相同的结构特征,进而表现出相近或相似的化学性质.因此,继铂类抗肿瘤配合物后,钯(II)配合物作为潜在抗肿瘤药物成为一个诱人的领域.本文综述了近年来钯(II)类抗肿瘤药物的研究进展,并探讨了其构效关系,这对于指导新型钯(II)类抗肿瘤药物的合成具有重要的参考价值. 相似文献
36.
FarzinMarandi 《结构化学》2014,(8):1184-1190
[Pb(TPT)(μ-I)2PbI2(μ-I)2Pb(TPT)] 1(TPT is the abbreviation of 3,5,6-tris(2-pyridyl)-1,2,4-triazine ligand) has been synthesized and characterized by elemental analysis, IR, 1HNMR spectroscopy and studied by thermal and electrochemical properties as well as X-ray crystallography. The single-crystal X-ray data show two different kinds of Pb2+ ions in 1 with coordination numbers of six, Pb1 = PbI6, and five, Pb2 = PbN3I2, with holodirected and hemidirected coordination spheres, respectively. The supramolecular features in 1 are negotiated through the weak but directional Pb···I, C–H···N and C–H···I interactions and aromatic π-π stacking interactions. 相似文献
37.
A new Cd(II) coordination polymer, namely, [Cd3(1,2,3-BTC)2(L)2]·2.25H2O (1, L = 2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-A][1,10]phenanthroline and 1,2,3-BTC = 1,2,3-ben- zenetricarboxylate), has been synthesized under hydrothermal conditions. The compound was characterized by single-crystal X-ray diffraction. It crystallizes in triclinic, space group Pī with α = 11.650(2), b = 12.240(2), c = 19.760(4) A, α = 72.01(3), β = 77.11(3), γ = 83.48(3)°, V = 2609.4(9) A3, Z = 2, C56H31Cd3Cl2F2N8O14.25, Mr = 1489.99, Dc = 1.896 g/cm3, F(000) = 1466, μ(MoKa) = 1.401 mm^-1, R = 0.0401 and wR = 0.1104. Compound 1 shows a 1D chain structure, and the neigh- boring 1D chains of 1 are joined together by π···π interactions to result in a 2D supramolecular layer. In addition, the luminescent property of 1 has been studied in the solid state at room temperature. 相似文献
38.
A new coordination compound with formula [Tb(2-TC)3(DMF)]n (1, 2-TC = 2-thio- phenecarboxylic ligand and DMF = dimethylformamide) was synthesized by solvothermal method. The structure of compound 1 was determined by single-crystal X-ray diffraction analyses, and characterized by elemental analyses, IR and powder X-ray diffraction. Structure analysis reveals compound 1, exhibiting a one-dimensional chain structure, crystallizes in triclinic space group P21/c, with a = 9.2751(19), b = 16.490(3), c = 15.865(5) A, β = 118.98(2)°, V= 2122.7(9)A3, D,. = 1.916 g/cm3, Mr= 612.45 (C18H15NO7S3Tb), F(000) = 1196,μ(MoKa) = 3.67 mm-1, Z = 4, R = 0.0616 and wR = 0.0962 for 3865 observed reflections (I 〉 2o(I)), and R = 0.1092 for all data. Meanwhile, the photoluminescent properties of compound 1 were also investigated in the solid state at room temperature. 相似文献
39.
Atom transfer radical polymerization of styrene(St) and methyl methacrylate(MMA) in bulk and in different solvents using activators generated by electron transfer(AGET ATRP) were investigated in the presence of a limited amount of air using FeCl3·6H2O as the catalyst, ascorbic acid sodium salt(AsAc-Na) as the reducing agent, and a cheap and commercially available tetrabutylammonium bromide(TBABr) as the ligand. It was found that polymerization in THF resulted in shorter induction period than that in bulk and in toluene for AGET ATRP of St, while referring to AGET ATRP of MMA, polymerization in THF showed three advantages compared with that in bulk and toluene: 1) shortening the induction period, 2) enhancing the polymerization rate and 3) having better controllability. The living features of the obtained polymers were verified by chain end analysis and chain-extension experiments. 相似文献
40.
A series of the copolymers of ethylene with 1-hexene(M1–M9) synthesized by metallocene catalyst Et[Ind]2ZrCl2/MAO was studied by differential scanning calorimetry and successive self-nucleation and annealing(SSA) thermal fractionation. The distribution of methylene sequence length(MSL) in the different copolymers was determined using the SSA method. The comonomer contents of samples M4 and M5 are 2.04 mol% and 2.78 mol%, respectively. Both M4 and M5 have low comonomer content and their MSL distribution profiles exhibit a monotonous increase trend with their MSL. The longest MSL of M5 is 167, and its corresponding molar percent is 43.95%, which is higher than that of M4. Moreover, the melting temperature(Tm) of M5 is also higher than that of M4. The comonomer contents of samples M7, M8, and M9 are 8.73 mol%, 14.18 mol% and 15.05 mol%, respectively. M7, M8, and M9 have high comonomer contents, and their MSL distribution profiles display unimodality. M7 has a lower peak value of 33 and a narrow MSL distribution, resulting in a Tm lower than that of M8 and M9. The MSL and its distribution are also key points that influence the melting behavior of copolymers. Sometimes, MSL and its distribution of copolymers have a greater impact on it than the total comonomer contents, which is different from traditional views. 相似文献