Wide Bandgap Semiconductor Technology Disciplines State Key Laboratory, School of Microelectronics, Xidian University , Xi'an 710071, P. R. China.
ACS Appl Mater Interfaces. 2017 Nov 22;9(46):40378-40385. doi: 10.1021/acsami.7b14254. Epub 2017 Nov 7.
The solvent-engineered one-step spin-coating method has been widely used to produce full-coverage CHNHPbI films for perovskite solar cells by forming an intermediate phase. However, the resultant CHNHPbI films usually contain numerous structural and compositional defects mainly resulting from the fast crystallization of the intermediate phase as well as the escape of CHNHI species induced by the inevitably thermal annealing recipe. Herein, a facile room-temperature intermolecular exchange route is proposed to enable conversion of the intermediate phase into uniform and ultra-flat CHNHPbI films. It can effectively inhibit the formation of structural and compositional defects in the resultant films, and even repair their inherent defects. As a result, the efficiency of perovskite solar cells can be boosted to 19.45% with a stabilized value of 18.55%, which is much higher than that from the ones fabricated by thermal annealing. This study suggests a facile and low-cost route to room-temperature fabrication of highly efficient perovskite solar cells including flexible ones.
溶剂工程一步旋涂法通过形成中间相被广泛用于制备全覆盖的 CHNHPbI 钙钛矿太阳能电池薄膜。然而，所得的 CHNHPbI 薄膜通常含有大量的结构和组成缺陷，主要是由于中间相的快速结晶以及不可避免的热退火工艺诱导的 CHNHI 物种的逃逸引起的。在此，提出了一种简便的室温分子间交换途径，使中间相转化为均匀和超平整的 CHNHPbI 薄膜。它可以有效地抑制所得薄膜中结构和组成缺陷的形成，甚至修复其固有缺陷。结果，钙钛矿太阳能电池的效率可以提高到 19.45%，稳定值为 18.55%，远高于热退火制备的钙钛矿太阳能电池的效率。本研究为在室温下制备高效的钙钛矿太阳能电池（包括柔性太阳能电池）提供了一种简便且低成本的途径。
