亚三维结构有机光电材料的合成与性能研究

发布时间：2019-05-20 17:57

【摘要】：近些年来,具有亚三维空间结构的有机分子材料在有机发光二极管、有机太阳能电池、有机白光照明等领域有广泛的研究和应用。以单键连接两个共轭链的亚三维结构是其中的代表之一。这种单键连接的亚三维空间结构不需要引入过多的烷基链就可以增加材料的溶解性,并且能够抑制材料的结晶性,促使材料形成无定型的玻璃态结构；分子由单键将两个共轭链连接起来,使得其具有一定的柔性,能够根据周围环境进行分子空间结构的自调整,确保了在溶液法制备有机半导体器件时能够形成致密有序的分子堆积；亚三维空间结构具有光学和电学性质的各向同性,有利于提高半导体器件的载流子迁移率。结合亚三维空间结构分子所具备的独特性质,我们采用联苯并噻唑和联噻吩为中心单元,构筑了一系列具有亚三维空间结构的窄带隙有机分子材料,探索这类亚三维结构有机分子作为电子给体材料在有机太阳能电池中的应用。论文主要分为四个部分： (1)采用5,5’-联-2,1,3-苯并噻唑为核,分别选用芴和咔唑单元为电子给体作为四臂,通过Stille coupling反应制备出具有不同供电子能力的电子给体-受体-给体型有机小分子太阳能电池给体材料(DFTBTF和DCzTBTCz)。通过分子模拟发现分子中心核的两个苯并噻唑所在平面的二面角约为60°,说明分子具有亚三维空间结构。我们将这两个化合物作为电子给体材料,通过与电子受体材料PC71BM共混,采用溶液法制备体异质结有机太阳能电池,均呈现出了一定的光伏性能。其中,DFTBTF的光伏性能为：光电转化效率(PCE)为0.74%,短路电流(Jsc)为2.47mA/cm2,开路电压(Voc)为1.09V,填充因子(FF)为27%。 (2)由于第一章中电子给体材料的分子量较小,成膜性相对较差,限制了其光伏性能。我们通过延长四臂共轭长度来提高分子量,从而改善其成膜性能,提高材料对太阳光的吸收能力,进而达到提高光伏器件性能的目的。我们分别制备出了摩尔分子量为4899g/mol的SFTBT和摩尔分子量为5021g/mol的SCzTBT单分散性大分子有机太阳能电池给体材料,同时制备出了与之相对应的一维线型分子LFTBT和LCzTBT。通过分子模拟计算发现,SFTBT和SCzTBT的中心核的两个苯并噻唑所在平面的二面角已经超过了70°,表明二者具有亚三维空间结构。通过将一维线型分子LFTBT作为电子给体,PC71BM作为电子受体,制备体异质结有机太阳能电池,其光电转化效率为PCE=2.84%, Jsc=2.95mA/cm2, FF=58.3%, Voc=0.94V;而与之对应的亚三维空间结构化合物SFTBT的PCE=3.38%, Voc=1.08V, Jsc=6.75mA/cm2, FF=43%, PCE比一维线型分子LFTBT的光电转化效率提高了19%。亚三维结构的SCzTBT比线型分子LCzTBT的光伏性能也有较大提高。 (3)我们以DHPT-SC为对比样品,采用3,3'-联噻吩为中心核单元,氰基异辛酸酯为拉电子单元,并将其放置于四臂末端,构筑具有亚三维空间结构的受体-给体-受体型窄带隙化合物ST10-CN-1, ST10-CN, ST14-CN和ST18-CN。通过分子模拟计算发现,中心核单元的两个噻吩所在平面的二面角已经超过了80°,表明这些分子具有亚三维空间结构。通过增加给电子基团噻吩的数目来延长共轭链长度,研究不同共轭长度对材料的热力学,光学以及电化学性质的影响。并以DHPT-SC为电子给体材料,PC71BM为电子受体材料,采用溶液法制备体异质结有机太阳能电池,其光伏性能为：PCE=1.70%, Jsc=5.35mA/cm2, Voc=0.92V, FF=34.0%; (4)以3,3'-联噻吩为核,以苯并噻唑为拉电子基团,合成了具有不同烷基链长度的窄带带隙化合物SC6BT, SC8BT, SC14BT。通过分子模拟计算发现,中心核单元的两个噻吩所在平面的二面角也超过了80°,其中SC8BT接近90。,表明这些分子具有亚三维空间结构。三个分子分别以正己基,异辛基和正十四烷基为取代基,通过延长烷基链的长度来改善材料的溶解性和成膜性,并研究了不同烷基长度取代基对材料的热力学,光学以及电化学性质的影响。 (5)采用PdCl2dppf作为催化剂,在没有联硼酸频那醇酯存在的条件下合成了具有光电特性的联芳基化合物2T-CN,4T-CN,6T-CN,并对反应中的溶剂,碱和配体进行了筛选。其中6T-CN展现出了较好的光伏性能：PCE=2.03%, Voc=0.86V, Jsc=6.24mA/cm2, FF=38%。
[Abstract]:In recent years, the organic molecular material with the sub-three-dimensional space structure has extensive research and application in the fields of organic light-emitting diodes, organic solar cells, organic white light illumination and the like. The sub-three-dimensional structure of two common chain is one of the representatives. The three-dimensional space structure of the single-bond connection does not need to introduce an excessive alkyl chain, so that the solubility of the material can be increased, such that the three-dimensional space structure has the isotropy of optical and electrical properties, And the carrier mobility of the semiconductor device can be improved. A series of narrow-band organic molecular materials with a sub-three-dimensional space structure are constructed by using the unique properties of the sub-three-dimensional space structure molecules, The application of such a sub-three-dimensional structure organic molecule as an electron donor material in an organic solar cell is explored. The thesis is divided into four parts: (1)5,5 '-1-2,1,3-benzo-2,1,3-benzene are used as the core, The electron donor-acceptor-donor-to-body organic small-molecule solar cell donor material (DTBTF and DCzTBTCz) with different electron-donating abilities was prepared by the Stille clinking reaction. The two benzene in the center of the molecule and the dihedral angle of the plane were found to be about 60 by molecular simulation. In this paper, the two compounds are used as electron donor materials, and the two compounds are mixed with PC71BM of the electron acceptor material, and a solution method is adopted to prepare the bulk heterojunction organic solar cell, which has certain photovoltaic performance, and the photovoltaic performance of the DFTBTF The photoelectric conversion efficiency (PCE) was 0.74%, the short-circuit current (Jsc) was 2.47 mA/ cm2, the open-circuit voltage (Voc) was 1.09 V, and the filling factor (FF) was 27. %. (2) Since the molecular weight of the electron donor material in the first chapter is small, the film-forming phase By extending the total length of the four arms to improve the molecular weight, the film-forming property of the four-arm is improved, and the absorption of the material on the sunlight is improved. The invention has the purposes of improving the performance of the photovoltaic device, and respectively preparing the SCTBT with the molar mass-weight of 4899g/ mol and the SCzTBT monodispersity macromolecular organic solar cell with the molar mass-weight of 5021g/ mol In the same time, one-dimensional linear molecules LFTBT and LCzTBT corresponding to them were prepared. The two-plane angles of the two benzene and the plane of the central core of SFTBT and SCzTBT have been exceeded by molecular simulation. By using one-dimensional linear molecule LFTBT as electron donor, PC71BM is used as electron acceptor, and PC71BM is used as electron acceptor, and its photoelectric conversion efficiency is PCE = 2.84%, Jsc = 2.95mA/ cm2, FF = 58.3%, and Voc = 0. The PCE = 3.38%, Voc = 1.08 V, Jsc = 6.75mA/ cm2, FF = 43%, and PCE of the three-dimensional three-dimensional structure compound SFTBT are higher than that of the one-dimensional linear molecule LFTBT by 19%. The photovoltaic performance of the SCzTBT of the sub-three-dimensional structure is higher than that of the linear molecule LCzTBT. Large increase. (3) We use the DHPT-SC In order to compare the samples, a 3,3 '-linked tetradecanoate is used as a central nuclear unit, and the cyanogen-isooctanoic acid ester is a tensile electronic unit and is placed at the tail end of the four arms to construct a receptor-donor-body-type narrow-band gap compound ST10-CN-1, ST10-CN, ST14-CN, and ST having a sub-three-dimensional space structure. 18-CN. It is found by molecular simulation that the two corners of the plane of the central nuclear unit have been more than 80 掳, indicating that these molecules have subthree. By increasing the number of the electron-donating groups to extend the length of the common chain, the thermodynamic, optical and electrochemical properties of the materials are studied. The effect of the properties of PC71BM is the electron donor material, PC71BM is the electron acceptor material, the solution method is used to prepare the bulk heterojunction organic solar cell, the photovoltaic performance is: PCE = 1.70%, Jsc = 5.35 mA/ cm2, Voc = 0.92 V, FF = 34.0%; (4)3,3 '-linked, with benzene and benzene The narrow-band band-gap compound SC6BT, SC8BT and SC14BT with different alkyl chain lengths were synthesized by means of molecular simulation. BT is close to 90. It is shown that these molecules have a sub-three-dimensional structure. The three molecules, respectively, are n-hexyl, isooctyl and n-tetradecyl as substituents, and the solubility and film-forming properties of the materials are improved by extending the length of the alkyl chain, and different alkyl-length substituents are also studied. the thermodynamic, optical, and electrical properties of the material (5) PdCl2dppf is used as a catalyst, and a biaryl compound 2T-CN, 4T-CN, 6T-CN, and the solvent, base and ligand in the reaction are screened, wherein the 6T-CN exhibits better photovoltaic performance: PCE = 2.03%, Voc = 0.86V, Jsc = 6.24 mA/ c
【学位授予单位】：华中科技大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：O626;TM914.4

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