无机半导体纳米材料在聚合物太阳能电池中的应用

发布时间：2018-06-17 02:48

本文选题：聚合物太阳能电池 + Cu2ZnSnSe4纳米粒子　；参考：《南昌大学》2015年硕士论文

【摘要】：近年来,聚合物太阳能电池因其制备成本较低、质量轻和可溶液制备等优点,克服了传统无机太阳能电池的成本高、机械性能差等缺点,而引起了人们的广泛关注。目前报道的基于富勒烯衍生物和共轭聚合物的有机太阳能电池的光电转换效率虽然已经超过10%,但无论是富勒烯衍生物还是聚合物,它们的吸光系数都较低,故对太阳光谱的捕获有限的弊端也逐渐显现出来。而且在体相异质结太阳能电池中,活性层的能级偏移和与电极接触的界面问题也是限制其发展的重要因素。吸光层与电极之间几毫伏的能垒就会导致电荷的累积与复合,因此建立有效的电荷抽取和良好的欧姆接触不仅可以增强器件的稳定性,也是提高光伏器件的重要策略。利用无机半导体纳米晶解决界面问题,首先要除去纳米粒子表面的多余绝缘配体,并保证其良好的分散。因为纳米粒子如果因高温配体交换而产生团聚现象,发生宏观相分离的话,就会使活性层和电极的界面之间相容性变差,接触不良,从而不利于激子的分离与自由电荷的传输。其次还要求抽取电子的界面材料可以形成连续不断的互穿网络结构,给电荷的抽取和载流子的传输提供良好的通道。本文采用平面性良好的氧化石墨烯(GO)提高配体交换的纳米晶的分散性和使用3D结构的半导体纳米晶修饰电极界面的方法解决了这两个问题。具体方法如下:第一,本文使用热注入的方法制备了四方晶型的Cu2ZnSnSe4纳米粒子作为正向器件的空穴传输层,取代了聚(3,4-亚乙二氧基噻吩)-聚(苯乙烯磺酸)(PEDOT:PSS),并用配体吡啶交换的方法去除纳米晶表面的绝缘有机物,来提高半导体纳米晶的电荷传输能力。但是交换后的纳米粒子容易聚集的现象会导致电池漏电。为了解决纳米粒子聚集的问题,加入少量氧化石墨烯(GO)作为负载和分散团聚半导体的纳米模板,不仅使纳米晶与氧化石墨烯上的官能团通过静电作用相互吸引,提高了纳米粒子的分散性,制备的纳米复合物还有助于调控阳极缓冲层的功函,从而使器件效率升高一倍。第二,本文通过制备CdSe四足体(TPs)纳米晶修饰反向器件中缓冲层Zn O的表面,形成3D网络结构的电子传输与抽取通道,有效的增加了短路电流,降低了ZnO的表面缺陷。导致整个电池的串联电阻降低,从而使填充因子从52.9%提高到61.3%;另外通过优化CdSe的浓度,使短路电流从7.39 mA·cm-2提高到8.03 mA·cm-2。
[Abstract]:In recent years, due to the advantages of low preparation cost, light quality and solution preparation, polymer solar cells have overcome the disadvantages of high cost and poor mechanical properties of traditional inorganic solar cells, which have aroused widespread concern. The photoelectric conversion of organic solar cells based on fullerene derivatives and conjugated polymers is reported. Although the exchange efficiency has exceeded 10%, the absorption coefficient of the fullerenes and polymers is low, so the limitation of the limited absorption of the solar spectrum is gradually apparent. In the bulk heterojunction solar cell, the energy level migration of the active layer and the interface problem with the electrode are also limited to its development. Factors. The energy barrier of a few milli V between the absorption layer and the electrode leads to the accumulation and recombination of the charge. Therefore, the establishment of effective charge extraction and good ohmic contact can not only enhance the stability of the devices, but also be an important strategy for improving the photovoltaic devices. The superfluous insulating ligand on the surface ensures its good dispersion, because if the nanoparticles are agglomerated because of the exchange of high temperature ligands, the compatibility between the interfaces of the active layer and the electrode will be worse and the contact is poor, which is not conducive to the separation of the exciton and the free charge transmission. Secondly, the extraction of the particles is also required to be extracted. The electronic interface materials can form a continuous interpenetrating network structure, providing a good channel for charge extraction and carrier transmission. In this paper, a good planar graphene oxide (GO) is used to improve the dispersibility of nanocrystals exchanged by ligand and the method of using the interface of semiconductor nanocrystalline modified electrode with 3D structure to solve this two The specific methods are as follows: first, we use the method of heat injection to prepare the tetragonal crystalline Cu2ZnSnSe4 nanoparticles as the cavity transport layer of the positive device, replacing the poly (3,4- B two oxygen thiophene) poly (PEDOT:PSS), and using the ligand pyridine exchange method to remove the insulating organic matter on the nanocrystalline surface. In order to solve the problem of nanoparticle aggregation, a small amount of graphene oxide (GO) can be used as a load and nano template to disperse the aggregate semiconductor, not only the nanocrystalline and the functional groups on the graphene oxide are not only passed. The electrostatic interaction attracts each other and improves the dispersion of the nanoparticles. The prepared nanocomposites can also help to control the work function of the anode buffer layer. Thus, the efficiency of the device is doubled. Second. By preparing the surface of the buffer layer Zn O in the CdSe tetrapod (TPs) nanocrystalline modified reverse device, the electronic transmission and pumping of the 3D network structure is formed. When the channel is taken, the short circuit current is effectively increased and the surface defect of ZnO is reduced. The series resistance of the whole battery is reduced, and the filling factor is increased from 52.9% to 61.3%, and the short circuit current is increased from 7.39 mA. Cm-2 to 8.03 mA. Cm-2. by optimizing the concentration of the battery.
【学位授予单位】：南昌大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;TM914.4

【共引文献】