Robust Unencapsulated Perovskite Solar Cells Protected by a Fluorinated Fullerene Electron Transporting Layer
Journal
ACS Energy Letters
Journal Volume
6
Journal Issue
9
Pages
3376-3385
Date Issued
2021
Author(s)
Huang, H.-H. et al.
Tsai, H.
Raja, R.
Lin, S.-L.
Ghosh, D.
Hou, C.-H.
Shyue, J.-J.
Tretiak, S.
Lin, K.-F.
Nie, W.
Abstract
The emergent perovskite photovoltaics technology faces challenges like the long-term durability combining moisture, thermal, and photo stresses that prevents them from competing with established technologies. Here, we introduce a series of new fluorinated fullerenes as an electron-transporting layer (ETL) for robust perovskite photovoltaics that deliver a high power conversion efficiency of 21.27% with substantially improved durability against environmental stressing. The hydrophobic nature of the new fullerene protects the unencapsulated perovskite cell with stability over 1400 h in 85% relative humidity. Notably, the unencapsulated device maintained 80% of their original performance (T80) after being immersed in water for over 10 min. Detailed characterizations suggest that the fluorinated fullerene can immobilize the cations in perovskites and passivate the surface traps. Therefore, the T80 lifetime of the devices under constant illumination reached 1920 h. On the basis of the accelerated test, we estimate a lifetime approaching 10 years with encapsulation. The successful demonstration of the new ETL can stimulate further research and momentum for future photovoltaic technology development. ? 2021 American Chemical Society.
Subjects
Conversion efficiency
Durability
Fullerenes
Perovskite
Accelerated tests
Electron transporting layer
Fluorinated fullerenes
High power conversion
Hydrophobic nature
Long term durability
Photovoltaic technology
Photovoltaics
Perovskite solar cells
SDGs
Type
journal article