FTO电极有机功能化修饰及其高效钙钛矿太阳能电池应用

发布时间：2018-06-22 23:23

本文选题：钙钛矿太阳能电池 + FTO电极　；参考：《西南大学》2017年硕士论文

【摘要】：能源危机是21世纪人类面临最大的问题之一,而太阳能既是国际公认的理想替代能源,也是人类可利用的可再生清洁能源。目前,以硅基为主的无机太阳能电池,其最高效率已经达到了25.6%,正在逐渐接近理论上限值30%。但是由于其生产工艺复杂,生产成本较高,从而制约着硅基太阳能电池的广泛应用。与半导体硅相比,有机/无机杂化钙钛矿材料具有优异的光伏性能,如适宜的禁带宽度、微米级的电子-空穴扩散长度、极高的光吸收系数和很好的载流子迁移率等。得益于此,在短短的几年时间里,研究者通过优化器件结构、材料及制备工艺,使器件的电池效率从9.7%升到了22.1%。但是,电池结构中的电子传输层需要高温煅烧制备,这无疑增加了器件的制备成本,阻碍了其进一步商业化进程。因此,在低温的条件下制备出高性能的钙钛矿太阳能电池器件,这对于钙钛矿太阳能电池的工业化发展有着重要的现实意义。本论文全面回顾了钙钛矿太阳能电池的发展史,简要地介绍了钙钛矿太阳能电池的实验内容,分析了提高钙钛矿太阳能光伏性能的方法,总结了钙钛矿太阳能电池的研究进展。在此基础上,本论文以低温制备高效钙钛矿太阳能电池为目标,探索通过界面修饰电极来提高其器件的性能,进一步分析其内在机理,为器件光伏性能的提升提供有益的借鉴。本文的研究内容包括以下两个部分:1、在100 o C低温下,在一步法基础上采用快速结晶法制备出致密的钙钛矿薄膜,其器件的光电转化效率为9.0%。由于FTO电极从钙钛矿薄膜中提取电子需要跨越很大一个能垒,这十分不利于电子的传输,进而限制了器件的光电转化效率。因此,利用邻二氯苯在UV照射下修饰FTO电极表面来增大其电极的功函数,从而有效降低了电子传输的能垒,进而提高了电池器件的光电转化效率。结果表明,经110 s的UV照射处理后,所制备的器件性能达到最佳,其光电转换效率为13.4%,开路电压接近1.0 V,短路电流密度为20.8 m A cm-2。2、利用PEI聚合物修饰FTO电极作为电子传输材料应用于平面钙钛矿太阳能电池。测试结果表明,PEI溶液的质量分数与电池性能有着密切关系。当PEI溶液的质量分数为0.04%时,所制备的钙钛矿太阳能电池性能最佳,其光电转化效率为10.4%,短路电流密度为20.09 m A cm-2,串联电阻为9.97?。进一步研究和分析证明,PEI作为电子传输材料,改善了FTO与钙钛矿界面的接触特性,有效地降低了器件的串联电阻,更有利于电子传输,从而提高了FTO电极的电子收集能力。综上所述,本论文主要揭示了通过表面有机功能化修饰可以有效改善FTO电极与钙钛矿界面电子传输,以及低温制备过程可简化器件结构,实现了提高钙钛矿太阳能电池性能同时降低了制备成本。
[Abstract]:Energy crisis is one of the biggest problems facing mankind in the 21st century, and solar energy is not only an ideal alternative energy, but also a renewable and clean energy that can be used by human beings. At present, the highest efficiency of inorganic solar cells based on silicon has reached 25.6 and is approaching the theoretical upper limit of 30. However, because of its complex production process and high production cost, it restricts the wide application of silicon-based solar cells. Compared with semiconductor silicon, organic / inorganic hybrid perovskite has excellent photovoltaic properties, such as suitable band gap, micron electron hole diffusion length, extremely high optical absorption coefficient and good carrier mobility. Thanks to this, in a few years, the researchers improved the battery efficiency from 9.7% to 22.1% by optimizing the device structure, materials and fabrication process. However, the electron transport layer in the battery structure needs to be calcined at high temperature, which undoubtedly increases the preparation cost of the device and hinders its further commercialization process. Therefore, high performance perovskite solar cell devices are fabricated at low temperature, which is of great practical significance for the industrial development of perovskite solar cells. This paper reviews the history of the development of perovskite solar cells, briefly introduces the experimental contents of perovskite solar cells, analyzes the methods to improve the photovoltaic performance of perovskite solar cells, and summarizes the research progress of perovskite solar cells. On this basis, the aim of this thesis is to prepare high efficiency perovskite solar cells at low temperature, to explore how to improve the performance of the device by interfacial modification electrode, and to further analyze its intrinsic mechanism, and to provide useful reference for the improvement of photovoltaic performance of the device. The research contents of this paper include the following two parts: 1. The compact perovskite thin films were prepared by rapid crystallization method at 100 o C at low temperature. The optoelectronic conversion efficiency of the device is 9. 0%. Because FTO electrodes need to cross a large barrier to extract electrons from perovskite thin films, this is not conducive to the transmission of electrons, which limits the photoelectric conversion efficiency of the devices. Therefore, by modifying the surface of FTO electrode with o-dichlorobenzene under UV irradiation, the work function of FTO electrode is increased, which can effectively reduce the energy barrier of electron transport and improve the photoelectric conversion efficiency of the battery device. The results show that after 110 s UV irradiation, the device has the best performance. Its photoelectric conversion efficiency is 13.4V, open circuit voltage is close to 1.0 V, short-circuit current density is 20.8 Ma cm-2.2. PEI polymer modified FTO electrode is used as electron transport material for planar perovskite solar cells. The results show that the mass fraction of PEI solution is closely related to the performance of the battery. When the mass fraction of PEI solution is 0.04, the performance of the perovskite solar cell is the best, the photoelectric conversion efficiency is 10.4, the short-circuit current density is 20.09 m / cm ~ (-2) and the series resistance is 9.97m ~ (-1). Further research and analysis show that the PEI as an electron transport material improves the contact characteristics between FTO and perovskite interface, effectively reduces the series resistance of the device, and is more favorable for electron transmission, thus improving the electron collection ability of the FTO electrode. To sum up, this thesis mainly reveals that the surface organic functionalization can effectively improve the electron transport between FTO electrode and perovskite interface, and the fabrication process at low temperature can simplify the device structure. The performance of perovskite solar cells was improved and the preparation cost was reduced.
【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM914.4

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