界面修饰对有机-无机杂化钙钛矿太阳能电池性能的影响

Effect of interface modification on performances of organicinorganic hybrid perovskite solar cells

作为近些年来最耀眼的明星材料之一,钙钛矿以其优异独特的光电特性成功吸引研究人员的广泛关注.自2009年报道了第一篇光电转换效率为3.8%的钙钛矿电池,到现在短短10年期间效率已经突破25.2%,几乎可以与商用多晶硅电池媲美.尽管其制备过程简单,但在薄膜的形成过程中很容易引入大量的缺陷.缺陷的存在会加速载流子的复合,阻碍载流子传输通道,不利于制备高效率的钙钛矿太阳能电池;同时也会影响钙钛矿电池工作的长期稳定性,加速材料的降解,阻碍了钙钛矿太阳能电池进一步商业化发展.因此,理解缺陷的存在机制并有效地抑制缺陷产生,对制备高性能长寿命器件至关重要.而界面修饰作为一种有效的钝化缺陷方法之一,已经被广泛使用.本文讨论了不同结构电池器件的缺陷产生位置及对器件性能的影响.分别从载流子传输层钝化策略和钙钛矿界面修饰策略入手,分析了常用的传输层/钙钛矿界面钝化缺陷的机制,指出了钝化策略发展的巨大优势,并对合适的钝化材料进行分类,希望能够对高重复性、高光电转换效率、长期工作稳定的钙钛矿太阳能电池发展提供有益的指导.

As one of the most dazzling star materials in recent years,perovskite has attracted extensive attention due to its unique photoelectric properties.Since the first report on 3.8%power conversion efficiency of perovskite solar cells(PSCs)was published in 2009,its efficiency has increased to 25.2%in a short period of 10 years,almost comparable to the efficiency of commercial polysilicon cells.However,due to its simple preparation process,it is easy to introduce a large number of defects in the film formation process.The defects accelerate the recombination of carriers and thus hindering the carrier transport channel,which is unfavorable for the preparation of high efficiency perovskite solar cells.Moreover,the existence of defects will affect the stability of PSCs,accelerate the degradation of materials,thereby hindering its further commercial development.Therefore,it is very important to understand the mechanism of defects and effectively suppress the generation of defects for the fabrication of high performance devices.As an effective passivation strategy,the interface modification has been widely used.In this paper,the locations of defects in different structures of devices and their effects on device performance are discussed.Based on the carrier transport layer passivation strategy and perovskite interface modification strategy,the mechanism of the passivation defects at the transport layer/perovskite interface is analyzed.The great advantages of passivation strategy and the classification of appropriate passivation materials are pointed out.It is hoped that this paper can provide useful guidance for developing the perovskite solar cells with high repeatability,high efficiency and long-term stability.