【作者】 武慧；

【导师】 邓振波；

【作者基本信息】 北京交通大学 ， 材料物理与化学， 2011， 硕士

【摘要】 近年来,有机太阳能电池取得了很大的进展。聚(3,4-乙撑二氧噻吩)：聚苯乙烯磺酸盐(PEDOT:PSS)作为一种新型的导电聚合物,因其在空气中结构稳定和电导率高,引起了研究人员的广泛关注。近期更有很多报道,通过加引入高沸点极性有机溶剂,如：二甲亚砜、山梨醇、丙三醇等,能够进一步改善PEDOT:PSS薄膜的导电特性。这种经过改良的导电聚合物材料,因具有相当高的电导率,已经被广泛应用于有机电致发光、有机太阳能电池等有机半导体器件的各个领域。大量的研究表明加入高沸点极性有机溶剂能提高PEDOT:PSS的电导率,但其物理本质、改性机理目前还缺乏系统的论述。本论文主要针对PEDOT:PSS的掺杂改性进行了一些工作：首先,通过引入二甲亚砜,采用控制变量法制备掺杂二甲亚砜的PEDOT:PSS薄膜并研究掺杂二甲亚砜对PEDOT:PSS导电性的影响及其本质。实验结果表明,当掺杂二甲亚砜为4%(体积分数)时,PEDOT:PSS薄膜的电导率最高,从8.84×10-2S/cm增加到89.69S/cm。同时通过研究紫外-可见吸收光谱、红外光谱分析、原子力显微镜(AFM)图表明二甲亚砜的加入未改变PEDOT:PSS的分子结构。接下来分别研究了未改性和改性后的PEDOT:PSS作为阳极缓冲层对有机太阳能电池器件性能的影响。结果表明：用未改性的PEDOT:PSS作阳极缓冲层所制备的电池器件短路电流和开路电压比没有阳极缓冲层的器件都有很大提高,短路电流密度(ISC)从1.04 mA/cm2提高到9.77 mA/cm2,开路电压(Voc)从0.03V提高到0.59V,填充因子(FF)由24.7%提高到48.01%,导致能量转换效率(PCE)从0.0079%提高到2.77%,提高了3个数量级。而改性后的PEDOT:PSS作为阳极缓冲层与未改性的PEDOT:PSS作阳极缓冲层的器件相比,器件的性能又有明显的提高。当掺杂4%二甲亚砜的PEDOT:PSS作阳极缓冲层时,器件的短路电流密度(Isc)从9.94 mA/cm2提高到14.56 mA/cm2。能量转换效率(PCE)从2.73%提高到3.34%。最后尝试用掺杂的PEDOT:PSS作有机太阳能电池的阳极。用PEDOT:PSS作有机太阳能电池的电极有望实现全溶液法制备有机太阳能电池,其制作成本低,制备方法简单。实验所制备的电池是反转有机太阳能电池,器件结构为ITO/Cs2CO3/P3HT:PCBM/PEDOT:PSS。主要研究了不同温度的退火对反转有机太阳能电池器件的影响。得出退火温度为120℃的电池器件性能好,器件的能量转换效率(PCE)为0.65%。虽然器件的能量转换效率只达到0.65%,但可以通过对器件不同方面的改进,如加入阳极缓冲层,改变整个器件的退火温度等方式进一步提高器件性能。更多还原

【Abstract】 In recent years, organic solar cells have made great progress. Poly (3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as a new type of conductive polymer, have caused widespread concern of researchers. Because it has the advantages:structure stability and high conductivity in the air. It is reported that adding high boiling point polar organic solvents can further improve the conductivity of PEDOT:PSS films, such as:dimethyl sulfoxide, sorbitol, glycerol, etc. The improved PEDOT:PSS as a conductive polymer material with high conductivity, has been widely used in various fields such as:electroluminescence, organic solar cells and other organic semiconductor devices, etc.Numerous studies show that adding high boiling point polar organic solvents can increase the conductivity of PEDOT:PSS,but there is a lack of systematic exposition in its physical nature and modification mechanism. The main works of this paper are listed as following:Firstly, high conductivity PEDOT:PSS films have been fabricated using controlling variables by adding dimethyl sulfoxide(DMSO). We make research of the effect of DMSO content on conductivity of PEDOT:PSS films and its modification mechanism. The experimental results show that the conductivity of PEDOT:PSS film mixed with 4% DMSO (volume ratio) is the highest, with the increase of conductivity from 8.84×10-2S/cm to 89.69S/cm. At the same time the absorption spectrum, the FTIR spectra and AFM images show that the addition of DMSO does not change PEDOT: PSS molecular structure.Secondly, we study that the effect of unmodified and modified PEDOT:PSS as anode buffer layer on the performance of organic solar cell device. The results show that: the device with PEDOT:PSS as anode buffer layer has the better performance, with the increase of short-circuit current density (Isc) from 1.04 mA/cm2 to 9.77 mA/cm2, the increase of open circuit voltage (Voc) from 0.03V to 0.59V, the increase of fill factor (FF) from 24.7% to 48.01% and the increase of photovoltaic energy conversion efficiency (PCE) from 0.0079% to 2.77%. When the wt% of DMSO is 4%, the performance of modified PEDOT:PSS as anode buffer layer achieved the best one:the short-circuit current density is 14.56 mA/cm2, the Open circuit voltage is 0.57V, the energy conversion efficiency is 3.34%. Finally, we try to fabricate organic solar cells using full-solution method with doped PEDOT:PSS as a transparent anode. It has the advantages of low cost and having simple preparation method. The structure of the organic solar cell device is ITO/Cs2CO3/P3HT:PCBM/PEDOT:PSS. It is studied that the effect of annealing on the performance of the organic solar cell devices at different temperatures. We find that when the annealing temperature is 120℃, the performance of the device shows a better one. The photoelectric conversion efficiency of the device is 0.65%. Although the energy conversion efficiency (PCE) of the device only reached 0.65%, we can improve the performance of devices by different aspects such as joining the anode buffer layer or changing the annealing temperature.更多还原