Lv Zheng, He Li, Jiang Haipeng, Ma Xiaojun, Wang Fengyou, Fan Lin, Wei Maobin, Yang Jinghai, Yang Lili, Yang Nannan
Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education, Jilin Normal University, Changchun 130013, China.
College of Mechanical Engineering, JiLin Engineering Normal University, Changchun 130052, PR China.
ACS Appl Mater Interfaces. 2021 Apr 14;13(14):16326-16335. doi: 10.1021/acsami.1c00896. Epub 2021 Mar 31.
An electron transport layer (ETL) with excellent conductivity and suitable band alignment plays a key role in accelerating charge extraction and transfer for achieving highly efficient planar perovskite solar cells (PSCs). Herein, a novel diluted-cadmium sulfide quantum dot (CdS QD)-assisted SnO ETL has been developed with a low-temperature fabrication process. The slight addition of CdS QDs first enhances the crystallinity and flatness of SnO ETLs so that it provides a promising workstation to obtain high-quality perovskite absorption layers. It also amazingly increases the conductivity of the SnO ETL by an order of magnitude and regulates the energy level matching between the SnO ETL and perovskite. These outstanding properties greatly accelerate the charge extraction and transfer. Thus, the MAPbI-based PSCs with such a diluted-CdSQD-assisted SnO ETL achieve a maximum power conversion efficiency of 20.78% and obtain a better stability of devices in air. These findings testify the importance and potential of semiconductor QD modification on ETLs, which may pave the way for developing such composite ETLs for further enhancing photovoltaic performance of planar PSCs.
具有优异导电性和合适能带排列的电子传输层（ETL）在加速电荷提取和转移以实现高效平面钙钛矿太阳能电池（PSC）方面起着关键作用。在此，通过低温制备工艺开发了一种新型的稀释硫化镉量子点（CdS QD）辅助的SnO ETL。少量添加CdS QDs首先提高了SnO ETL的结晶度和平整度，从而为获得高质量的钙钛矿吸收层提供了一个有前景的工作平台。它还令人惊讶地将SnO ETL的电导率提高了一个数量级，并调节了SnO ETL与钙钛矿之间的能级匹配。这些优异的性能极大地加速了电荷提取和转移。因此，具有这种稀释CdS QD辅助SnO ETL的基于MAPbI的PSC实现了20.78%的最大功率转换效率，并在空气中获得了更好的器件稳定性。这些发现证明了半导体量子点对ETL进行修饰的重要性和潜力，这可能为开发这种复合ETL以进一步提高平面PSC的光伏性能铺平道路。
