School of Materials Science and Engineering, State Centre for International Cooperation on Designer Low-Carbon and Environmental Material (SCICDLCEM), Zhengzhou University, Zhengzhou 450001, Henan, People's Republic of China.
Nanotechnology. 2018 Sep 21;29(38):385401. doi: 10.1088/1361-6528/aacf7c. Epub 2018 Jun 27.
As one of the significant electron transporting materials (ETMs) in efficient planar heterojunction perovskite solar cells (PSCs), SnO can collect/transfer photo-generated carriers produced in perovskite active absorbers and suppress the carrier recombination at interfaces. In this study, we demonstrate that a mild solution-processed SnO compact layer can be an eminent ETM for planar heterojunction PSCs. Here, the device based on chemical-bath-deposited SnO electron transporting layer (ETL) exhibits a power conversion efficiency (PCE) of 16.10% and with obvious hysteresis effect (hysteresis index = 19.5%), owing to the accumulation and recombination of charge carriers at the SnO/perovskite interface. In order to improve the carrier dissociation and transport process, an ultrathin TiO film was deposited on the top of the SnO ETL passivating nonradiative recombination center. The corresponding device based on the TiO@SnO electron transporting bi-layer (ETBL) exhibited a high PCE (17.45%) and a negligible hysteresis effect (hysteresis index = 1.5%). These findings indicate that this facile solution-processed TiO@SnO ETBL paves a scalable and inexpensive way for fabricating hysteresis-less and high-performance PSCs.
作为高效平面异质结钙钛矿太阳能电池（PSCs）中重要的电子传输材料（ETM）之一，SnO 可以收集/转移钙钛矿活性吸收体中产生的光生载流子，并抑制界面处的载流子复合。在本研究中，我们证明了经过温和溶液处理的 SnO 致密层可以作为平面异质结 PSCs 的杰出 ETM。基于化学浴沉积 SnO 电子传输层（ETL）的器件表现出 16.10%的功率转换效率（PCE）和明显的滞后效应（滞后指数=19.5%），这是由于在 SnO/钙钛矿界面处电荷载流子的积累和复合。为了改善载流子的解离和输运过程，在 SnO ETL 上沉积了一层超薄的 TiO 薄膜以钝化非辐射复合中心。基于 TiO@SnO 电子传输双层（ETBL）的相应器件表现出高 PCE（17.45%）和可忽略的滞后效应（滞后指数=1.5%）。这些发现表明，这种简便的溶液处理 TiO@SnO ETBL 为制备无滞后和高性能 PSCs 铺平了一条可扩展且经济的途径。
