We report a simple and effective method to realize desirable interfacial property for inverted planar perovskite solar cells (PSCs) by using small molecule ethanediamine for the construction of a novel polyelectrolyte hole transport material (P3CT-ED HTM). It is found that P3CT-ED can not only improve the hole transport property of P3CT-K but also improve the crystallinity of adjacent perovskite film. In addition, the introduction of ethanediamine into P3CT realigns the conduction and valence bands upwards, passivates surface defects and reduces nonradiative recombination. As a consequence, compared to P3CT-K hole transport layer (HTL) based devices, the average power conversion efficiency (PCE) is boosted from 17.2% to 19.6% for the counterparts with P3CT-ED, with simultaneous enhancement in open circuit voltage and fill factor. The resultant device displays a champion PCE of 20.5% with negligible hysteresis.

我们报告了一种简单有效的方法，可通过使用小分子乙二胺构建新型聚电解质空穴传输材料（P3CT-ED HTM）来实现倒置平面钙钛矿太阳能电池（PSC）的理想界面性能。发现P3CT-ED不仅可以改善P3CT-K的空穴传输性能，而且可以改善相邻钙钛矿膜的结晶度。此外，将乙二胺引入P3CT可使导电带和价带向上重新排列，钝化表面缺陷并减少非辐射重组。因此，与基于P3CT-K的空穴传输层（HTL）的设备相比，与P3CT-ED对应的设备相比，平均功率转换效率（PCE）从17.2％提高到19.6％，同时开路电压和填充因子。