Ahmmed Shamim, He Yulu, Kayesh Md Emrul, Karim Md Abdul, Matsuishi Kiyoto, Islam Ashraful
Photovoltaic Materials Group, Center for Green Research on Energy and Environmental Materials, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba 305-0047, Ibaraki, Japan.
Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8573, Ibaraki, Japan.
ACS Appl Mater Interfaces. 2024 Jun 26;16(25):32282-32290. doi: 10.1021/acsami.4c05180. Epub 2024 Jun 12.
In the planar heterostructure of perovskite-based solar cells (PSCs), tin oxide (SnO) is a material that is often used as the electron transport layer (ETL). SnO ETL exhibits favorable optical and electrical properties in the PSC structures. Nevertheless, the open circuit voltage () depletion occurs in PSCs due to the defects arising from the high oxygen vacancy on the SnO surface and the deeper conduction band (CB) energy level of SnO. In this research, a cerium (Ce) dopant was introduced in SnO (Ce-SnO) to suppress the loss of the PSCs. The CB minimum of SnO was shifted closer to that of the perovskite after the Ce doping. Besides, the Ce doping effectively passivated the surface defects on SnO as well as improved the electron transport velocity by the Ce-SnO. These results enabled the power conversion efficiency (PCE) to increase from 21.1% (SnO) to 23.0% (Ce-SnO) of the PSCs (0.09 cm active area) with around 100 mV of improved and reduced hysteresis. Also, the Ce-SnO ETL-based large area (1.0 cm) PSCs delivered the highest PCE of 22.9%. Furthermore, a of 1.19 V with a PCE of 23.3% was demonstrated by Ce-SnO ETL-based PSCs (0.09 cm active area) that were treated with 2-phenethylamine hydroiodide on the perovskite top surface. Notably, the unencapsulated Ce-SnO ETL-based PSC was able to maintain above 90% of its initial PCE for around 2000 h which was stored under room temperature condition (23-25 °C) with a relative humidity of 40-50%.
在基于钙钛矿的太阳能电池（PSC）的平面异质结构中，氧化锡（SnO）是一种经常用作电子传输层（ETL）的材料。SnO电子传输层在PSC结构中表现出良好的光学和电学性能。然而，由于SnO表面高氧空位产生的缺陷以及SnO较深的导带（CB）能级，PSC中会出现开路电压（）损耗。在本研究中，在SnO（Ce-SnO）中引入铈（Ce）掺杂剂以抑制PSC的 损耗。Ce掺杂后，SnO的CB最小值向钙钛矿的CB最小值靠近。此外，Ce掺杂有效地钝化了SnO表面的缺陷，并通过Ce-SnO提高了电子传输速度。这些结果使功率转换效率（PCE）从PSC（活性面积0.09平方厘米）的21.1%（SnO）提高到23.0%（Ce-SnO），开路电压提高了约100 mV，滞后现象减少。此外，基于Ce-SnO电子传输层的大面积（1.0平方厘米）PSC的最高PCE为22.9%。此外，基于Ce-SnO电子传输层的PSC（活性面积0.09平方厘米）在钙钛矿顶表面用氢碘酸2-苯乙胺处理后，实现了1.19 V的开路电压和23.3%的PCE。值得注意的是，未封装的基于Ce-SnO电子传输层的PSC在室温条件（23-25°C）、相对湿度40-50%下储存约2000小时后，能够保持其初始PCE的90%以上。
