咔唑衍生物DiPICz载流子传输性能的理论研究

依据Marcus理论, 在密度泛函理论水平下对咔唑衍生物Dibenzo[2,3: 5,6]pyrrolizino[1,7-bc]indolo-[1,2,3-lm]carbazole(DiPICz)的电子结构和传输性质进行系统研究. 计算结果表明, DiPICz的电子迁移率(5.81×10^-2 cm²·V^-1·s^-1)反常地高出空穴迁移率(6.02×10^-4 cm²·V^-1·s^-1)2个数量级, 表明稠合修饰可能是一种潜在的转变传输材料极性的手段. 分析发现, 导致DiPICz具有较好电子传输性质的原因在于相对较小的电子重组能和较好的晶体堆积方式. 在其鱼骨型堆积的晶体中, 存在着滑移的π-π及边对面的 CH…N和CH…π相互作用. 这些相互作用由于形成二维的电荷传输通道, 从而在电子传输中起着重要作用.     

含有酰亚胺结构单元的氮杂和硫杂稠五环分子的合成与性能研究

设计合成了含有酰亚胺结构单元的氮杂和硫杂稠五环共轭分子1和2, 并对它们的物理化学性质进行了研究. 实验结果显示酰亚胺基团的引入不仅使得分子具有良好的溶解性, 而且有效地降低分子的HOMO和LUMO能级. 化合物1的单晶结构显示其共轭核具有良好的平面性. 单晶中, 化合物1通过强的π-π相互作用形成二聚体, 二聚体之间存在强的氢键相互作用. 基于化合物2的薄膜场效应晶体管表现出p-型场效应晶体管行为, 其最高迁移率为2.75×10^-3 cm²·V^-1·s^-1.     

含杂原子的并五苯类似物合成及场效应性能研究

以N,N'-二苯基-1,4-苯二胺为原料, 合成了含硫和氮杂原子的并五苯类似物, 用可见-紫外吸收光谱和电化学测试对这类化合物进行表征, 确定了其光学带隙及轨道能级, 与并五苯相比它们具有低的最高占用分子轨道能级. 得到了三苯并二噻嗪的单晶结构, 分子具有平面结构, 分子间具有强的π…π相互作用和N…S相互作用. 首次将该类并五苯类似物应用于有机薄膜场效应晶体管中, 器件显示好的场效应特性, 迁移率为0.01 cm²·V^-1·s^-1.     

印刷半导体碳纳米管薄膜晶体管光电性能研究

本文研究了聚[(2,7-9,9-二辛基芴基)-4,7-双(噻吩-2-基)苯并-2,1,3-噻二唑]（PFO-DBT）分离的半导体碳纳米管薄膜晶体管的光电性能。在超声和高速离心辅助下,PFO-DBT能够从商业化单壁碳纳米管中选择性分离出高纯的半导体碳纳米管。用得到的半导体碳纳米管溶液通过气溶胶喷墨印刷方法构建出高性能印刷薄膜晶体管器件。印刷碳纳米管薄膜晶体管表现出高的开关比（10⁷）和高迁移率（15.6 cm²·V^-1·s^-1）。并且所有制备的印刷薄膜晶体管具有很好的光敏感特性和很好的稳定性。     

二邻苯二胺合镍(Ⅱ)载流子传输性能的理论研究

利用密度泛函理论UB3LYP方法, 对二邻苯二胺合镍(Ⅱ)(PHDANI)的基态和离子态几何结构进行全优化, 模拟其双自由基特性. 运用势能面曲线法计算了PHDANI的空穴和电子重组能. 从晶体结构中选出所有可能最近的载流子传输路径, 计算相应的传输积分, 结合Marcus电荷转移理论探讨PHDANI的载流子传输性质. 计算结果表明, 在单重态双自由基特性下, 空穴和电子的迁移率分别达到0.253和0.135 cm²·V^-1·s^-1, 空穴和电子传输迁移率都很高且能达到平衡, 从理论层面上阐明了PHDANI可以作为很好的双极性传输材料.     

十字交叉型π共轭分子3,6-二苯-1,2,4,5-(2′,2″-二苯基)-苯并二噁唑的电子结构和电荷传输性质的理论研究

采用密度泛函理论的B3LYP方法, 在6-31G(d)基组水平下研究了以三联苯和二苯基苯并噁唑构成的十字交叉型共轭分子3,6-二苯基-1,2,4,5-(2′,2″-二苯基)-苯并二噁唑的电子结构和电荷传输性质. 通过对分子的重组能和晶体中分子间电荷传输积分的计算得到该分子的空穴迁移率为0.31 cm²·V^-1·s^-1, 电子迁移率为0.11 cm²/(V·s). 计算结果表明, 空穴的传输主要是通过三联苯方向上两端苯环的“边对面”的相互作用以及分子中心π体系的错位重叠相互作用来实现的. 而电子的传输路径主要是通过苯并噁唑方向的π-π重叠相互作用来实现. 通过分析分子正负离子态的Mulliken电荷发现, 正电荷较多分布在三联苯方向上, 而负电荷较多分布在苯并噁唑方向上. 计算结果表明, 电子和空穴的传输分别在分子相互交叉的不同方向上, 有利于电子和空穴的平衡传输.     

全印刷碳纳米管薄膜晶体管构建及电性能研究

利用纳米压印和电刷镀技术在PET基体上制作出大面积金源、漏电极阵列。分别采用钛酸钡复合材料为介电层,印刷银电极为顶电极,聚芴-二噻吩基吡咯并吡咯二酮(PF8DPP)分离的半导体碳纳米管为有源层,在柔性基体上构建出全印刷碳纳米管薄膜晶体管器件和反相器。全印刷碳纳米管薄膜晶体管的开关比和迁移率分别达到4×10⁴和6 cm²·V^-1·s^-1,且器件表现出零回滞特性。构建的反相器在V_dd =8 V时,其增益可以达到12。     

基于荧蒽酰亚胺的立构规整共轭高分子的合成与场效应晶体管性能

荧蒽是一种典型的具有高度平面结构的稠环芳烃，中心独特的五元环赋予了它缺电子特性，因此非常适合用于构筑稠环酰亚胺类受体砌块。然而，由于功能化位置受限，荧蒽酰亚胺砌块还未能成功用于共轭高分子的构建。本工作基于一种具有不对称结构的2,3-酰亚胺荧蒽砌块，成功构建了两个新型给受体(D-A)型共轭高分子，即无规结构的PF1以及立构规整结构的PF2,并详细表征了它们的光物理性质以及场效应晶体管器件性能。研究发现，PF2由于立构规整结构形成了相对有序的分子聚集以及更加优异的薄膜形貌，所制备的场效应晶体管器件表现出1.72×10^-5 cm²·V^-1·s^-1的空穴迁移率，而基于无规PF1制备的场效应晶体管则未能测出器件性能。本工作不仅表明2,3-酰亚胺荧蒽作为受体砌块在构建新型D-A型高分子半导体上具有一定的发展潜力，且进一步证实了分子规整性对分子堆积行为和光电性能的关键影响。     

基于多层二硒化钨的高性能场效应晶体管的实验优化和理论模拟

采用微机械剥离法制备了基于不同厚度的高质量WSe₂纳米片的场效应晶体管(WSe₂-FETs), 研究了其性能的影响因素. 通过调控WSe₂纳米片及介电层的厚度、 测试温度及退火处理等, 结合理论模拟分析, 获得了WSe₂-FETs的最佳电学性能. 最终, 基于7层WSe₂纳米片的场效应晶体管表现出最优异的电学性能, 室温下载流子迁移率可达93.17 cm²·V^?1·s^?1; 在78 K低温下, 载流子迁移率高达482.78 cm²·V^?1·s^?1.     

聚(茚并芴-三苯胺)的合成及性能

设计并合成了一类新的可用于有机场效应晶体管(OFET)的聚合物半导体材料聚(茚并芴-三苯胺)(pIFTPA1~4), 通过核磁共振谱和凝胶渗透色谱等对聚合物进行了表征, 同时对其场效应薄膜晶体管性能进行了测试. 结果表明, 这些聚合物形成了无定形半导体膜, 在空气中稳定, 其载流子迁移率远高于聚三苯胺(pTPA)类材料, 其中pIFTPA1载流子迁移率高达4×10^-2 cm²/(V·s), 开关比为10⁶.     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Copper catalyzed/mediated synthetic methodology for ebselen and related isoselenazolones

Scope of the copper catalyzed/mediated selenium-nitrogen coupling reaction has been studied for the synthesis of isoselenazolones. It is noticed that the 2-chloro, 2-bromo-, and 2-iodo-aryl amides substrates can be exploited in the selenium-nitrogen coupling reaction by employing 25-100 mol % of CuI/1,10-phenanthroline (L) and potassium carbonate as a base in DMF. Furthermore, electron rich 2-chloro-arylamides also underwent selenium-nitrogen coupling reaction to give biologically important selenium-nitrogen heterocycles. Also, copper-catalyzed selenium-nitrogen coupling reaction has been meticulously applied for the synthesis of diaryl diselenides having methoxy, amine, and amide functionality from respective aryl iodides in the presence of stoichiometric amount of succinimide as an external Se-N coupling partner.     

Knoevenagel condensation catalyzed by novel Nmm-based ionic liquids in water

A series of novel N-methyl morpholine (Nmm) based ionic liquids with 1,2-propanediol group were synthesized and used as catalysts for Knoevenagel condensation at room temperature in water. Under the effect of the catalyst, various aldehydes or aliphatic ketones could react with a wide range of activated methylene compounds well, including malononitrile, alkyl cyanoacetate, cyanoacetamide, β-diketone, barbituric acid, 2-arylacetonitrile and thiazolidinedione. Furthermore, most of the products could be separated just by filtrating and washing with water. Additionally, the catalyst is recyclable and applicable for the large-scale synthesis.     

Construction of polyheterocyclic spirotetrahydrothiophene derivatives via sulfa-Michael/aldol cascade reaction

A series of polyheterocyclic spirotetrahydrothiophene derivatives were obtained in moderate to excellent yields via a catalyst-free sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 under mild conditions. We also present the first asymmetric sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 with moderate to good enantioselectivities catalyzed by readily available chiral phase-transfer catalysts (PTCs).     

Suzuki-Miyaura reactions of the soluble guanylate cyclase inhibitor NS2028: a non-product specific route to C-8 substituted analogues

Both soluble guanylate cyclase (sGC) inhibitors ODQ 1 and NS2028 2 are synthesized via improved protocols. In the former case treating 3,4-dihydroquinoxalin-2(1H)-one oxime 8, which can be prepared in two steps from 1,2-benzenediamine, with 1,1′-carbonyldiimidazole (CDI) gives the dihydro-ODQ 10 that in the presence of KMnO₄ oxidises to give ODQ 1 in an overall yield of 46% starting from 1,2-benzenediamine. In the latter case, the synthesis affords NS2028 2 from 2-amino-4-bromophenol 3 in three steps with an overall yield of 85% and avoids the need for chromatography. Furthermore, Suzuki-Miyaura reaction conditions are described that enable the preparation of 8-aryl and 8-heteroaryl derivatives of NS2028 directly from NS2028 2. Finally, demethylation of the 8-(methoxyphenyl) substituted analogues afforded the 8-(hydroxyphenyl) derivatives 40-42. All new products are fully characterised.