可溶液加工D-A型有机小分子太阳能电池给体材料合成及其光伏性能研究

发布时间：2018-05-26 22:26

本文选题：小分子 + 有机太阳能电池　；参考：《中国海洋大学》2014年硕士论文

【摘要】：随着煤、石油等传统能源的日益消耗，寻找新型、无污染的环境友好型的可再生能源已成为一个世界性的课题，太阳能由于具有无污染，取之不尽等自身的优点而受到人类的关注和开发利用。有机太阳能电池由于制备工艺简单、廉价、易于大面积制备及柔性等优点，而成为世界范围内的研究热点。有机体异质结太阳能电池根据活性层中给体材料的不同又可分为聚合物太阳能电池和小分子太阳能电池。文献报道的聚合物体异质结太阳能电池的最高光电转换效率已达9.2%，有机小分子体异质结太阳能电池的最高光电转换效率亦已达到8.12%。小分子太阳能电池与聚合物太阳电池相比：具有分子易于设计修饰、提纯方便、分子结构明确、合成重复性好、分子量确定等优点，而备受关注。本文是根据给体-受体（D-A）的设计思路，合成了一系列有机小分子给体材料并对其光伏性能进行了研究。在第二章中，我们将硫靛引入到小分子体系中。硫靛是用噻吩取代异靛外侧的苯环。噻吩环比苯环显示更强的给电子性，而且基于硫靛的共轭聚合物的光吸收可以延伸到更长波长，我们合成了含硫靛的小分子TIDO2T在薄膜中的吸收可拓宽至871nm。结果表明，与异靛相比，基于硫靛的小分子吸收光谱可以扩展到近红外（NIR）。TIDO2T的光学带隙为1.42eV，HOMO能级为-4.87eV，LUMO能级为-3.45eV。基于TIDO2T的有机太阳能电池显示出1.14％的光电转换效率（PCE），0.44V的开路电压（Voc），7.76mA/cm2的短路电流（Jsc）和33％的填充因子（FF）。这是首次将硫靛成功地应用到可溶液加工的有机太阳能电池中。在第三章中，我们将并噻唑和苯并噻二唑两种受体通过噻吩π-电桥连接，合成了含双受体的小分子DTTz-DTBTT。该小分子具有良好的热稳定性，优良的溶解性和成膜性。DTTz-DTBTT的光学带隙为1.65eV，HOMO能级为-5.05eV，LUMO能级为-3.07eV。基于DTTz-DTBTT和PC61BM的有机太阳能电池得到0.66V的Voc，5.11mA/cm2的Jsc，和48%的FF，1.64％的PCE。测试结果表明，基于两种不同受体的小分子对于给体材料的设计是一种有效的策略。在第四章中，通过引入二维苯并二噻吩单元，进一步降低了小分子的带宽，有利于获得高的短路电流和开路电压。引入强吸电子的氰基乙酸辛酯和电子受体苯并三氮唑单元，有效地调节了分子的HOMO和LUMO能级，相应的HOMO和LUMO能级分别为-5.13eV和-3.31eV，使得小分子与PC61BM的能级匹配更理想。采用简单旋涂法制造工艺，基于D(CATBTzT)BDT:PC61BM的有机太阳能电池得到3.61％的PCE与0.93V的高开路电压；该太阳能电池也可以显示高达72％的FF。在第五章中，我们通过Stille偶合反应合成了两种窄带隙的有机小分子DRTBTTBDT和DRTBTTBDTT，其光学带隙的分别是1.80eV和1.81eV。相应的HOMO能级分别为-5.09eV和-5.13eV， LUMO能级分别为-3.28eV和-3.33eV。二维苯并二噻吩的引入，有效地调节了HOMO、LUMO能级，降低了材料的能级，获得了比较高的开路电压。通过对材料体系的微调，，可以改善电流或是电压，但获得的小分子在与PC61BM共混的器件整体的光电转换效率偏低。DRTBTTBDT最优化光电转换效率PCE为1.01%，开路电压（Voc）为0.70V，短路电流为4.15mA/cm2（Jsc）和填充因子（FF）35％。退火温度100℃时，DRTBTTBDT和DRTBTTBDTT得到最大的迁移率值分别为0.004和0.016cm2/Vs，二维的小分子表现出了比较高的迁移率。
[Abstract]:With the increasing consumption of traditional energy such as coal and oil, it has become a worldwide topic to find new and pollution-free environmental friendly renewable energy. Solar energy has been paid attention to and exploited by mankind because of its pollution free and inexhaustible advantages. With the advantages of large area preparation and flexibility, it has become a hot topic in the world. The solar cells of organism heterojunction can be divided into polymer solar cells and small molecular solar cells according to the different material in the active layer. The highest photoelectric conversion efficiency of the solar energy cell of the polymeric heterojunction heterojunction has reached 9.2%, The maximum photoelectric conversion efficiency of organic small molecular heterojunction solar cells has reached 8.12%. small molecular solar cells compared with polymer solar cells, which have the advantages of easy molecular design, easy purification, clear molecular structure, good reproducibility, and molecular weight determination.
Based on the design idea of donor acceptor (D-A), a series of organic small molecule donor materials have been synthesized and their photovoltaic properties have been studied.
In the second chapter, thiophene is introduced into a small molecular system. Thiophene is a substituted phenyl ring with thiophene to replace the lateral indigo. The thiophene ring specific benzene ring shows a stronger electron property, and the optical absorption of the conjugated polymer based on the indigo can extend to longer wavelengths. We have synthesized the absorption of the small molecule TIDO2T containing Indigo in the film. The results of 871nm. show that, compared with isoindigo, the small molecular absorption spectrum based on indigo can extend to the near infrared (NIR).TIDO2T optical band gap is 1.42eV, HOMO energy level is -4.87eV, LUMO energy level is -3.45eV. based on TIDO2T based organic solar cells showing 1.14% photoelectric conversion efficiency (PCE), 0.44V open circuit voltage (Voc), shorter. Jsc and 33% fill factor (FF). This is the first time that sulfur indigo has been successfully applied to solable organic solar cells.
In the third chapter, we combine the thiophene and benzothiazole two azole two receptors through the thiophene pion bridge to synthesize a small molecule DTTz-DTBTT. containing two receptors. The small molecule has good thermal stability. The excellent solubility and the optical band gap of the membranous.DTTz-DTBTT are 1.65eV, the HOMO level is -5.05eV, and the LUMO level is -3.07eV. based on DTTz-DTBT. T and PC61BM organic solar cells get 0.66V Voc, 5.11mA/cm2 Jsc, and 48% FF, and 1.64% PCE. test results show that small molecules based on two different receptors are an effective strategy for the design of donor materials.
In the fourth chapter, by introducing the two-dimensional benzo two thiophene unit, the bandwidth of the small molecules is further reduced and the short circuit current and the open circuit voltage are obtained. The HOMO and the LUMO energy levels of the molecules are effectively regulated by the introduction of the strong absorption electron cyanoacetate Octyl and the electron acceptor benzo three azazole unit, and the corresponding HOMO and LUMO levels are respectively - 5.13eV and -3.31eV make the small molecules match the energy level of PC61BM more ideally. Using a simple spin coating process, a high open circuit voltage of 3.61% PCE and 0.93V is obtained based on D (CATBTzT) BDT:PC61BM organic solar cells; the solar cell can also show up to 72% FF.
In the fifth chapter, we synthesized two narrow band gap organic small molecules DRTBTTBDT and DRTBTTBDTT through the Stille coupling reaction, and the corresponding HOMO energy levels of 1.80eV and 1.81eV. respectively are -5.09eV and -5.13eV, and LUMO levels are -3.28eV and -3.33eV. two-dimensional benzo two thiophene respectively. By reducing the energy level of the material, the higher open circuit voltage is obtained. By the fine tuning of the material system, the current or voltage can be improved, but the obtained small molecules are low in the overall photoelectric conversion efficiency of the whole PC61BM blends.DRTBTTBDT, PCE is 1.01%, the open circuit voltage (Voc) is 0.70V, and the short circuit current is 4.1. When the annealing temperature of 5mA/cm2 (Jsc) and filling factor (FF) 35%. is 100 C, the maximum mobility values of DRTBTTBDT and DRTBTTBDTT are 0.004 and 0.016cm2/Vs respectively, and the two-dimensional small molecules show higher mobility.
【学位授予单位】：中国海洋大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM914.4

【共引文献】