Photovoltaic molecules based on vinylene-bridged oligothiophene applied for bulk-heterojunction organic solar cells

We have synthesized two photovoltaic molecules（HEX-3TVT-ID and EH-3TVT-ID） based on vinylenebridged oligothiophene applied as donor for the solution-processable bulk-heterojunction organic solar cells（OSCs）. Vinylene unit was introduced as π-bridge in the oligothiophenes with 1,3-indenedione as end group and 4,4’-dihexyl-2,2’：5’,2’-terthiophene or 3’,4’-di（octan-3-yl）-2,2’：5’,2’-terthiophene as core,respectively. Due to the different substituent positions of the alkyl group relative to the vinylene unit in the terthiophene, HEX-3TVT-ID and EH-3TVT-ID show different optical and electrochemical properties, corresponding to the photovoltaic performance of the OSCs devices. The power conversion efficiency（PCE） of the OSCs based on a blend of HEX-3TVT-ID and PC71BM（1：0.8, weight ratio, 0.5% CN） reached 2.3%. In comparison, the OSCs based on the blend of EH-3TVT-ID and PC71BM in the weight ratio of 1：1 without the additive show a higher PCE of 2.7%, with a typically high VOC of 0.93 V, under the illumination of AM 1.5, 100 mW cm-2.

Theoretical Study on Electronic Transport Properties of Oligothiophene Molecular Devices

Based on the first-principles computational method and the elastic scattering Green＇s function theory, we have investigated the electronic transport properties of different oligothiophene molecular junctions theoretically. The numerical results show that the difference of geometric symmetries of the oligothiophene molecules leads to the difference of the contact configurations between the molecule and the electrodes, which results in the difference of the coupling parameters between the molecules and electrodes as well as the delocalization properties of the molecular orbitals. Hence, the series of oligothiophene molecular junctions display unusual conductive properties on the length dependence.

Theoretical study of structural and electronic properties of oligo(thiophene-phenylene)s in comparison with oligothiophenes and oligophenylenes

In this work, a quantum-chemical investigation on the structural and opto-electronic properties of oligo（thiophene-phenylene） （4TP） is carried out. The results are discussed in comparison with the properties of corresponding oligothiophene （8T） and oligophenylene （8P）. As the opto-electronic properties of this type of conducting polymers are governed by their electronic band gap, we shall also present a comparison among HOMO, LUMO and band gap energies of these three materials.

Organic Photovoltaic Properties Based on Oligothiophenes

The ITO/5T/PCH/Al1 device has a short circuit current of 3.4 mA/cm^2, an open circuit voltage of 2.1 V, fill fact of 27.5 % and photoelectric conversion efficiency of 2.5 %.

Luminescence Properties of Europium and Terbium Complexes with Pyridine or Bipyridine Linked Oligothiophene Ligand

With an aim to develop novel luminescence materials, europium and terbium complexes of 2, 5-(2-thiophene)-pyridine (TPY), 5, 5′-bis(5-(2, 2′-bithiophene))-2, 5-pyridine (B2TPY) and 5, 5′-bis(5-(2, 2′-bithiophene))-2, 2′-bipyridine (B2TBPY) were synthesized, and their luminescence properties were studied. The complexes exhibited ligand-sensitized emission, which was typical of Eu(Ⅲ) and Tb(Ⅲ) ions. The excitation spectra of Eu(Ⅲ) and Tb(Ⅲ) complexes with TPY (or B2TPY or B2TBPY) show similar bands as these with the ligands. It suggests that, the excitation energy is absorbed by TPY or B2TPY or B2TBPY, the energy transfers from its excited single state to its triplet state, and finally transfers from the ligands to Eu(Ⅲ) and Tb(Ⅲ) ions. The luminescence of Eu(Ⅲ) and Tb(Ⅲ) ions in the TPY or B2TPY or B2TBPY complexes indicates that the metal ions are efficiently excited by the absorbed energy from excitation of the ligands.

A Rapid Solid-phase Synthesis to Soluble Oligothiophene Molecular Wires

A novel method for the preparation of oligothiophene molecular wires is described via a bi-directional solid-phase synthesis. Using an alternating sequence of bromination and Stille coupling reactions, oligomers were obtained up to the heptamer in excellent yield and purity.

Organic photovoltaic devices with high open-circuit voltage based on oligothiophene derivatives

For the purpose of developing organic photovoltaic devices with good performance characteristics, we have fabricated two devices using 4T-CHO, 5T-CHO and PTCDA. The ITO/4T-CHO/PTCDA/Al device has a Voc of 2.45 V and photoelectric conversion efficiency of 2.76%. The ITO/ST-CHO/PTCDA/Al device has a Voc of 2.1 3V and photoelectric conversion efficiency of 2.90%. The two devices have higher Voc （2.45 and 2.13 V）. It is possible that intennolecular hydrogen bonding between -CHO group of nT-CHO and carboxylic dianhydride of PTCDA contribute to enhance the efficiency by promoting interracial electron transfer and eliminating the subconducting band trap sites.

Flexible organic photovoltaic devices based on oligothiophene derivatives

For the purpose of developing flexible organic photovoltaic devices, we have fabricated two flexible devices using 5-formyl- 2,2′：5′,2″：5″,2′″-quaterthiophene （4T-CHO）, 5-formyl-2,2′：5′, 2″：5″,2′″：5′″,2″″-quinquethiophene （5T-CHO） and 3,4,9,10-perylenetertracarboxylic dianhydride （PTCDA）. The PET-ITO/4T-CHO/PTCDA/A1 device has an open circuit voltage （Voc） of 1.56 V, photoelectric conversion efficiency of 0.77%. The PET-ITO/5T-CHO/PTCDA/A1 device has a Voc of 1.70 V, photoelectric conversion efficiency of 0.84%. The two flexible devices have high Voc （1.56 and 1.70 V）. It is possible that intermolecular hydrogen bonding between -CHO group of nT-CHO and carboxylic dianhydride of PTCDA contributes to enhancing the efficiency by promoting interfacial electron transfer and eliminating the subconducting band trap sites.

pFTAA: a high affinity oligothiophene probe that detects filamentous tau in vivo and in cultured neurons

Tauopathies describe a group of neurodegenerative diseases in which the protein tau,encoded by the gene MAPT,is aberrantly misfolded,leading to tau aggregation,neural dysfunction,and cell death（Spillantini and Goedert,2013）.In Alzheimer＇s disease（AD）,tau forms the characteristic intracellular neurofibrillary tangles（NFTs）,which are thought to be the major cause of neurodegeneration（Bloom,2014）.In other tauopathies,including frontotemporal dementia with Parkinsonism linked to chromo- some 17 （FTDP-17T）, corticobasal degeneration and progressive supranuclear palsy, there are specific forms of tau aggregates and filaments without any amyloid pathology, demonstrating tau＇s po- tent disease-causing potential （Spillantini and Goedert, 2013）. Tau is a microtubule （MT） binding protein, which becomes abnormally hyperphosphorylated on several residues prior/during the process of aggregation, thereby causing loss of its MT binding activity （Mandelkow and Mandelkow, 2012）.

Alzheimer’s Disease Aβ-Amyloid Plaque Morphology Varies According to APOE Isotype

Background: The apolipoprotein E (APOE, gene;apoE, protein) ε4 allele is the most commonly identified genetic risk factor for typical late-onset sporadic Alzheimer’s disease (AD). Each APOE ε4 allele roughly triples the relative risk for AD compared to that of the reference allele, APOE ε3. Methods: We have employed hyperspectral fluorescence imaging with an amyloid-specific, conformation-sensing probe, p-FTAA, to elucidate protein aggregate structure and morphology in fresh frozen prefrontal cortex samples from human postmortem AD brain tissue samples from patients homozygous for either APOE ε3 or APOE ε4. Results: As expected APOE ε4/ε4 tissues had a significantly larger load of CAA than APOE ε3/ε3. APOE isoform-dependent morphological differences in amyloid plaques were also observed. Amyloid plaques in APOE ε3/ε3 tissue had small spherical cores and large coronas while amyloid plaques in APOE ε4/ε4 tissues had large irregular and multi-lobulated plaques with relatively smaller coronas. Despite the different morphologies of their cores, the p-FTAA stained APOE ε3/ε3 amyloid plaque cores had spectral properties identical to those of APOE ε4/ε4 plaque cores. Conclusions: These data support the hypothesis that one mechanism by which the APOE ε4 allele affects AD is by modulating the macrostructure of pathological protein deposits in the brain. APOE ε4 is associated with a higher density of amyloid plaques (as compared to APOE ε3). We speculate that multilobulated APOE ε4-associated plaques arise from multiple initiation foci that coalesce as the plaques grow.

Self-assembled nanostructures of a series of linear oligothiophene derivatives adsorbed on surfaces

Many previous studies have shown that the molecular structures of oligothiophene derivatives including molecular skeleton and alkyl chains have a significant effect on their self-assemblies on the surface.In this work, a series of linear oligothiophene derivatives(DCV-n T-Hex, n = 3~11) modified with terminal dicyanovinyls and alkyl chains were adopted to further investigate the different assembly behaviors at liquid-solid interface by scanning tunneling microscopy(STM). Interestingly, via the hydrogen bonding and van der Waals interactions, DCV-3T-Hex formed zigzag and flower structures while DCV-n T-Hex(n = 4~11) formed lamellar structures. Density functional theory(DFT) calculations show that for the most energetically favorable configurations of DCV-n T-Hex, the different distribution of alkyl chains affected intermolecular interactions, and ultimately led to the different assembled structures. The zigzag and flower structures of DCV-3T-Hex had preferential thermodynamic stability compared to other structures of DCV-n T-Hex(n = 4~11). In addition, self-assembled nanostructures of DCV-n T-Hex molecules with even numbers(n = 4, 6, 8, 10) were overall more stable than those with odd numbers(n = 5, 7, 9,11), and the stability of the self-assembled structure was weakened with the extension of the molecular backbone, individually. The orientation of molecular alkyl chains was found to greatly affect the intermolecular interactions and thus leading to various self-assembly structures of DCV-n T-Hex(n = 3~11).

低聚噻吩/富勒烯混合液中富勒烯吸收对荧光猝灭效率影响的校正方法

借助荧光猝灭可以观测和研究导电高聚物与富勒烯之间的电子转移效率及机理.但对链长较短的低聚噻吩(2T^7T)来说,由于不能避开富勒烯的吸收范围而仅对低聚噻吩进行选择性激发,从而导致获取的猝灭率失实.给出了富勒烯吸收作用对荧光猝灭效率影响的校正方法、物理模型和数学推导过程.校正后,在低聚噻吩/富勒烯混合液中荧光光谱波形轮廓与低聚噻吩溶液中荧光光谱波形轮廓的一致性,证实了该校正方法的可行性.

新型低聚噻吩衍生物的设计、合成及其液晶性能的研究

设计、合成了一系列新型低聚噻吩衍生物N ,N′ 双烷烃基 5 ,5″ 二溴基 2 ,2′ :5′ ,2″ 三噻吩 4,4″ 二酰胺 [N ,N′ dialkyl 5 ,5″ dibromo 2 ,2′ :5′ ,2″ terthiophene 4,4″ dicarboxamide] (DNCnDBr3T ,n =5 ,8,16,18) .示差扫描量热法 (DSC)测定的结果及偏光光学显微镜观察的结果显示 ,DNC18DBr3T ,DNC16DBr3T ,DNC8DBr3T具有近晶A形液晶性质 ,DNC5DBr3T不具有液晶性质 .为了探讨分子间氢键对液晶形成的影响 ,设计、合成了新型低聚噻吩衍生物 4,4″ 双烷烃酯 5 ,5″ 二溴基 2 ,2′ :5′ ,2″ 三噻吩 [4,4″ bis(alkyloxycarbonyl) 5 ,5″ dibromo 2 ,2′ :5′ ,2″ terthiophene] (DOCnDBr3T ,n =5 ,8,16,18) .测定和观察的结果发现 ,DOCnDBr3T (n =5 ,8,16,18)不具有液晶的性质 .这个结果表明 ,酰胺基的存在对于液晶的形成起着重要的作用 .测定DNC18DBr3T在结晶状态和液晶状态下的红外光谱 。

低聚噻吩衍生物的合成及液晶性能

设计合成了一系列新型低聚噻吩衍生物N ,N’ 双烷烃基 5 ,5” 二溴基 2 ,2’ :5’ ,2” 三噻吩 4 ,4” 二酰胺 (DNCnDBr3T ,n=5 ,8,1 6 ,1 8) .示差扫描量热法测定及偏光光学显微镜观察的结果显示 ,DNC18DBr3T、DNC16 DBr3T、DNC8DBr3T具有近晶A相液晶性质 .研究结果表明 ,烷基链的长度以及分子间氢键对于液晶的形成起着重要作用 .另外 ,还考察了DNCnDBr3T(n =8,1 6 ,1 8)的光。

吸电子基团修饰的三联噻吩及其对纳晶TiO2电极的敏化

设计合成了吸电子基团(2氰-基-2-羧基乙烯基)修饰的三联噻吩3T-CCV,研究了它的光物理和光电化学性质.密度泛函计算证明,3T-CCV受光激发可有效地发生分子内电荷分离.研究表明,在模拟太阳光AM1.5(70 mW/cm2)照射下,以3T-CCV作为光敏剂的纳晶TiO2太阳电池的光电转换效率达到3.25%.

一系列单硅烷-寡聚噻吩共聚高分子膜中电荷传导研究

研究了一系列由单硅烷和寡聚噻吩组成的共聚高分子膜(PSnT,n表示寡聚噻吩单元中噻吩环的个数)在较宽掺杂率范围内载流子的迁移率变化规律.结果表明,掺杂率极低(<0·2%)时各膜中的载流子迁移率接近,几乎不受n的影响;随着膜的掺杂率的增加,各PSnT膜中的迁移率相继增大,n增大,迁移率在更低的掺杂率处开始增大,其增幅随着n的增加而增大.PS14T迁移率的增幅超过4个数量级,已与电化学合成的聚噻吩膜中观察到的迁移率增幅相当,表明此共聚物中的π-共轭长度已足以再现聚噻吩传导性能.

一种新型十元噻吩大环化合物的合成及晶体结构

以2,2′-二溴-5,5′-二(三甲硅基)-[3,3′]联噻吩为原料,在无水无氧低温条件下制备出一种新的十元大环低聚噻吩化合物,并用核磁共振、红外光谱以及高分辨质谱对其结构进行了表征.X射线单晶衍射分析确定了其晶体属于单斜晶系,C2/c空间群,分子中心为十元大环结构呈"扭船型"构象,平均内径约为0.3970 nm.

结构规整有序的寡聚噻吩修饰9,9′-螺二芴衍生物的光物理性质及其电化学聚合(英文)

研究了结构规整有序的寡聚噻吩修饰的9,9′-螺二芴衍生物在溶液中和在固体膜状态下的光物理性质,发现在四氢呋喃的稀溶液中,随着有效共轭长度的增加这些化合物的最大吸收峰和发射峰发生了明显的红移.实验结果表明,9,9′-螺二芴骨架中的9位螺碳原子明显地阻断了二个共轭片段的共轭效应,使它们成为了二个独立的共轭链节.此外,还进一步研究了这些化合物的电化学聚合性质.

以三苯胺为核的星形齐聚噻吩衍生物的光学、电化学和光伏性能

合成了两种以三苯胺为核的星形齐聚噻吩衍生物,三[4-(2-噻吩)苯]胺(TTPA)和三[4-(5′-氰基-2′-噻吩)苯]胺(TCTPA),应用紫外-可见吸收光谱、荧光光谱和循环伏安法研究了它们的光物理和电化学性能,计算了它们的HOMO、LUMO能级和电化学带隙,并讨论了分子结构与光电性能之间的关系。研究结果表明,TCTPA中氰基的引入使最大吸收峰和发射峰与TTPA相比均发生了红移,TCTPA的起始氧化电位和还原电位均向阳极移动。分别以TTPA和TCTPA为电子给体材料,3,4,9,10-二萘嵌苯四甲酸二酐(PTCDA)为电子受体材料,采用真空蒸镀方法制备了两种p-n异质结有机光伏器件:(a)ITO/TTPA/PTCDA/Al和(b)ITO/TCTPA/PTCDA/Al,研究了它们的光伏性能。两种器件的光电转换效率分别为0.55%和1.23%,TCTPA结构中引入氰基后使其光伏性能显著提高。原子力显微镜观察膜表面形态发现,TCTPA具有更好的有序性,更易发生取向,这可能是其光伏性能较好的主要原因。