聚3-己基噻吩：非富勒烯太阳能电池中的量子效率损失和电压损失

聚3-己基噻吩(P3HT)以其合成工艺简单、成本低廉的优势,成为有机光伏领域中最具吸引力的电子给体材料之一。然而,目前P3HT: 非富勒烯太阳能电池的光伏性能仍然较差。在本工作中,我们证明了与P3HT: 富勒烯太阳能电池相比,较快的电荷转移态的非辐射衰减速率(K_nr)是导致P3HT: 非富勒烯太阳能电池中较低的量子效率和较高的电压损失的原因。然后,我们研究了基于非富勒烯受体ZY-4Cl的太阳能电池的工作机理。研究结果表明与P3HT: 非富勒烯体系相比,P3HT: ZY-4Cl中K_nr的降低改善了器件的量子效率,同时降低了电压损失。K_nr降低的原因可以部分归因于电荷转移态能量的增加。此外,给体分子和受体分子之间的距离(DA间距)的增大也是K_nr减少的重要原因。因此,我们得出结论：为了提高P3HT太阳能电池的性能,需进一步降低器件的K_nr,这可通过增加活性层中的DA间距来实现。     

非富勒烯聚合物太阳电池研究进展

综述了以p-型共轭聚合物为给体、n-型有机半导体为受体的非富勒烯聚合物太阳电池光伏材料最新研究进展,包括n-型共轭聚合物和可溶液加工小分子n-型有机半导体(n-OS)受体光伏材料,以及与之匹配的p-型共轭聚合物给体光伏材料.介绍的n-型共轭聚合物受体光伏材料包括基于苝酰亚胺(BDI)、萘酰亚胺(NDI)以及新型硼氮键连受体单元的D-A共聚物受体光伏材料,目前基于聚合物给体(J51)和聚合物受体(N2200)的全聚合物太阳电池的能量转换效率最高达到8.26%.n-OS小分子受体光伏材料包括基于BDI和NDI单元的有机分子、基于稠环中心给体单元的A-D-A型窄带隙有机小分子受体材料等.给体光伏材料包括基于齐聚噻吩和苯并二噻吩(BDT)给体单元的D-A共聚物,重点介绍与窄带隙A-D-A结构小分子受体吸收互补的、基于噻吩取代BDT单元的中间带隙二维共轭聚合物给体光伏材料.使用中间带隙的p-型共轭聚合物为给体、窄带隙A-D-A结构有机小分子为受体的非富勒烯聚合物太阳电池能量转换效率已经突破12%,展示了光明的前景.最后对非富勒烯聚合物太阳电池将来的发展进行了展望.     

A-D-A型小分子电子给体中的端基优化和高效率光伏器件

<正>相较于传统的无机太阳能电池,有机太阳能电池(OSCs)具备成本低、重量轻、可通过溶液加工方式制备柔性器件等诸多优点,已经成为具有重要应用前景的太阳能利用方式之一~(1,2)。自1995年俞刚等发明了具有本体异质结结构(BHJ)的OSC以来~3,采用共轭聚合物电子给体和小分子电子受体材料构建BHJ光伏活性层的电池能量转换效率     

利用非共价构象锁定设计小分子受体材料

<正>聚合物太阳能电池(PSC)具有质轻,成本低,可通过溶液加工的方法大面积制备柔性器件等优点,受到广泛关注~(1–3)。目前,体异质结(BHJ)结构的PSC主要采用共轭高分子给体材料和受体材料共混制备光电活性层。2015年,占肖卫课题组首先报道了一类非富勒烯的高效率的稠环电子受体(FREAs)~(4,5)。这类受体具有化学结构易修饰,能级易调控以及跟给体聚合物吸收互补等显著优点,受到研究者们的青睐。近3年来,基于FREAs构建     

面向非富勒烯型有机光伏电池的聚合物给体材料设计

可溶液加工的有机光伏电池(OPV)是一种具有重要应用潜力的新型光伏技术。在OPV技术的发展过程中,富勒烯衍生物作为电子受体材料占据了相当长时间的统治地位,因此聚合物给体材料设计中对如何与富勒烯受体材料相互匹配考虑较多。最近几年来,基于聚合物给体和非富勒烯有机受体的OPV电池,简称为非富勒烯型NF-OPV,得到了十分快速的发展。在此类电池中,聚合物电子给体和非富勒烯型电子受体材料均起到了十分重要的作用。相比于较为经典的富勒烯型OPV,NF-OPV对聚合物给体的光电特性和聚集态结构提出了新的要求。因此,本文针对NF-OPV的特点,重点介绍NF-OPV对聚合物给体材料的吸收光谱、分子能级以及聚集态结构等特征的新要求,总结最近几年来的相关进展,并在此基础上进一步讨论聚合物电子给体材料面临的挑战和展望。     

聚合物太阳电池光伏材料

聚合物太阳电池由共轭聚合物给体和可溶性富勒烯衍生物受体的共混膜夹在ITO透光电极和金属电极之间所组成,具有结构简单、成本低、重量轻和可制成柔性器件等突出优点,近年来受到广泛关注。聚合物太阳电池中的给体和受体光伏材料是决定器件性能的关键。本文综述了共轭聚合物给体和富勒烯受体光伏材料的最新研究进展,对共轭聚合物受体材料和给体-受体双缆型共轭聚合物光伏材料的研究进展也进行了简要介绍。在共轭聚合物给体材料中对聚噻吩衍生物以及含有苯并噻二唑的窄带隙D-A共聚物进行了重点介绍。     

理性调控聚合物给体-非富勒烯受体的混溶性制备高效率有机太阳能电池※

除了非富勒烯受体的设计与合成, 聚合物给体的选择对非富勒烯太阳能电池的光伏性能同样重要. 本工作设计并合成一种共轭骨架无sp³杂化碳原子的新型非富勒受体(命名为MDB), 并将其作为模型化合物研究给受体混溶性和分子有序堆积对太阳能电池性能的影响. 本工作选择三种宽带隙聚合物给体(PM6、J71和P3HT)与MDB共混来制备太阳能电池. 得益于MDB和PM6之间适度的混溶性, 由二者组成的混合膜表现出合适的相分离, “face-on”的分子取向和更紧密有序的分子堆积, 从而促进了载流子传输, 并抑制了电荷复合. 因此基于PM6:MDB的器件实现了13.26%的优异光电转换效率, 远高于基于J71:MDB (8.16%)和P3HT:MDB (0.45%)的器件. 该工作证明了给体-受体之间合适的混溶性是实现高效率有机太阳能电池的关键因素之一, 这对有机光伏材料的设计与合成具有重要指导意义.     

非富勒烯型聚合物太阳电池取得超过11%的光伏效率

非富勒烯型聚合物太阳电池,由于其非富勒烯类受体材料可易于通过分子设计获得与聚合物给体材料互补的光吸收、匹配的电子能级从而有可能获得更高的效率,而受到了越来越多的关注.最近的研究发现,采用非富勒烯型受体材料与一种新型中等带隙聚合物给体材料可实现创纪录的11.2%的能量转换效率.这一成果预示非富勒烯受体将成为聚合物太阳电池研究下一波的新热点,并有可能成为这一类太阳电池新的突破口.     

基于苝酸酯受体光伏器件的性能表征

近十几年来,基于有机聚合物半导体材料的太阳能电池,由于具有价格低廉,易于加工,不受材料种类限制和易于制备大面积柔性器件等优点,而受到极大关注．自从1992年发现从共轭聚合物的基态到富勒烯存在光诱导电子转移现象以来,有机聚合物太阳能电池的研究取得了较大进展,研究较多的是共轭聚合物为给体(D),富勒烯为受体(A)的体系,能量转换效率可达3．3％,苝酸酯是一类液晶材料,其结构高度有序且含有4个吸电子的酰基,使得它们适合电子传输,且在普通有机溶剂中具有良好的溶解性,与共轭聚合物有较好的相容性,因此可制成薄膜,本文的研究表明,苝酸酯也是一类良好的电子受体,与共轭聚合物给体匹配,可用于制备光伏器件——太阳能电池。     

通过调节共轭聚合物侧链实现可绿色溶剂加工的非富勒烯太阳能电池

有机太阳能电池(OSC)经过长期的发展,其能量转换效率(PCE)已快速推进至14%–16%,基本接近可商业化应用的范围,但在目前所见报道的高效率OSC器件的制备过程中,活性层薄膜的加工大多采用氯苯、二氯苯、氯仿等毒性较高的含卤/芳香性试剂,此类试剂对环境及人类健康的危害非常高。在本工作中,我们基于已报道的高效率给体共轭聚合物PBDB-T,通过扩大共轭侧链结构与增长柔性烷基侧链的方式,合成了新型给体聚合物PBDB-DT。PBDB-DT中较长的柔性烷基侧链保证了其在低毒性溶剂四氢呋喃(THF)溶液中良好的溶解度,同时,扩大的共轭侧链也有效增强了其在THF中的溶液聚集作用,这一特性对于在非富勒烯型OSC器件中获得较好的光伏性能尤其重要。当采用非富勒烯小分子IT-M作为电子受体材料时,以THF为主溶剂加工的基于PBDB-DT:IT-M的OSC器件可以获得10.2%的能量转换效率。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.