基于噻吩—苯—噻吩及吡咯并吡咯二酮聚合物的合成及光伏性能研究

发布时间：2018-02-06 00:19

本文关键词： 聚合物太阳能电池噻吩-苯-噻吩吡咯并吡咯二酮能量转换效率　出处：《湘潭大学》2017年硕士论文　论文类型：学位论文

【摘要】：聚合物太阳能电池因其清洁、溶液可加工和低成本等特点成为全世界科学界研究的热点。近年来,在多国科研工作者的共同努力下,聚合物本体异质结聚合物太阳能电池(BHJ PSCs)最高的能量转换效率已经超过12%。但是,离实现商业化应用还有一定的距离。在此背景下,我们分别设计合成了三个A-D-A型,三个D-A-D型,以及一系列基于吡咯并吡咯二酮(DPP)的共轭聚合物给体材料,并对目标聚合物的光物理、电化学等性能进行了系统的研究。同时,我们分别制备了基于目标聚合物的BHJ PSCs,并对其光伏性能进行了测试。本论文主要研究内容如下:1.以噻吩-苯-噻吩(TBT),吡咯并吡咯二酮(DPP)和侧链苯并噻二唑(DTBT)共聚,合成了三个三元无规共轭聚合物GP1,GP2和GP3,不同烷氧基链对聚合物的光物理、电化学及光伏性能的影响进行了系统的研究。基于具有长烷基链的聚合物GP1的PSCs表现出较低的Jsc。具有短烷基链的聚合物GP3和PC61BM共混表现出较明显的微相分离和最大的表面粗糙度。GP2具有最合适的烷基链,所以它有着最有序的π-π堆积,最宽的吸收光谱和最合适的微相分离形态,因此,基于GP2的BHJ PSCs器件获得了3.31%的PCE。2.以吡咯并吡咯二酮(DPP)衍生物与烷基取代的苯并二噻吩(BDTT)和噻吩-苯-噻吩(TBT)共聚合成了三个三元无规共轭聚合物GP4,GP5和GP6。通过调整BDTT和TBT的比例,聚合物的热稳定性、光物理性质、电化学性质、π-π堆积距离、层间距以及光伏性能都得到优化。经过研究发现,随着TBT含量的增加,聚合物的π-π堆积距离变小,但是HOMO能级增加,这导致聚合物器件表现出高的Jsc和低的Voc。基于GP5的BHJ PSCs器件表现出了较高的Jsc和FF及PCE(4.18%)。3.将苯并二噻吩(BDTT)分别和侧链型吡咯并吡咯二酮(TTDPP)及主链型吡咯并吡咯二酮(DPP)共聚合成了一系列新的聚合物,并测试了其光物理、电化学及光伏性能。随着TTDPP含量的增加,聚合物在短波区域的吸收增强,π-π堆积距离减小,HOMO能级降低,这使聚合物器件得到较高的Voc。最后,基于GP10的器件表现出较高的PCE 4.46%,这一研究结果表明设计合成具有两个不同电子受体单元的无规三元共聚物是一种平衡Jsc和Voc从而获得高PCE的有效方法。此外,通过溶剂退火对GP8器件进行优化,由于溶剂退火使共混膜进行重组,得到更好的相分离形态,从而得到更高的Jsc和PCE(4.74%)。
[Abstract]:Polymer solar cells have become the focus of scientific research all over the world due to their characteristics of cleanliness, processability and low cost. In recent years, with the joint efforts of researchers from many countries, polymer solar cells have become the focus of scientific research all over the world. The highest energy conversion efficiency of polymer bulk heterojunction polymer solar cell (BHJ PSCs) has exceeded 12. However, there is still a certain distance from commercial application. We have designed and synthesized three A-D-A, three D-A-D, and a series of conjugated polymer donor materials based on pyrrolidine-pyrrolidinone diketone (DPP), and the photophysics of the target polymer. The electrochemical properties were systematically studied. At the same time, we prepared BHJ PSCs based on the target polymer. The photovoltaic properties were tested. The main contents of this thesis are as follows: 1. Copolymerization of thiophene benzene-thiophene (TBTT), pyrrolidine dione (DPP) and side chain benzothiadiazole (DTBTT) was carried out. Three ternary random conjugated polymers GP1GP2 and GP3 were synthesized. The photophysical properties of different alkoxyl chains on the polymers were investigated. The effects of electrochemical and photovoltaic properties were systematically studied. The PSCs based on the polymer GP1 with long alkyl chain showed a lower JSC. The polymer GP3 and PC61BM with short alkyl chain were studied systematically. The blend shows obvious microphase separation and maximum surface roughness. GP2 has the most suitable alkyl chain. So it has the most ordered 蟺-蟺 stacking, the widest absorption spectrum and the most suitable microphase separation form, so. The BHJ PSCs device based on GP2 has obtained 3.31% PCE.2.The derivatives of pyrrolidine-diketone and alkyl substituted benzodithiophene (BDTT) have been obtained. Three ternary random conjugated polymers (GP4) were synthesized by copolymerization with thiophene benzene-thiophene (TBT). GP5 and GP6. By adjusting the ratio of BDTT and TBT, the thermal stability, photophysical properties, electrochemical properties and 蟺-蟺 packing distance of the polymer were studied. The interlayer spacing and photovoltaic properties are optimized. It is found that with the increase of TBT content, the 蟺-蟺 stacking distance of the polymer decreases, but the HOMO energy level increases. This resulted in high Jsc and low Vocabulary in polymer devices, and high Jsc and FF and 4.18 in BHJ PSCs devices based on GP5. A series of new polymers were synthesized by copolymerization of benzodithiophene (BDTT) with side chain pyrrolidine-pyrrolidone (TTDPP) and main chain type of pyrrolidine-pyrrolidone (DPP) respectively. The photophysical, electrochemical and photovoltaic properties of the polymer were tested. With the increase of TTDPP content, the absorption of the polymer in the shortwave region increased, and the 蟺-蟺 packing distance decreased and the Homo energy level decreased. Finally, the GP10 based devices show a higher PCE 4.46%. The results show that the design and synthesis of random terpolymer with two different electron receptor units is an effective way to balance Jsc and Voc in order to obtain high PCE. The GP8 devices were optimized by solvent annealing. Because of the recombination of the blend films by solvent annealing, a better phase separation morphology was obtained, and a higher Jsc and PCE4.74g were obtained.
【学位授予单位】：湘潭大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O631.3;TM914.4

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