Air‐stable p‐type SnF2:Cs2SnI6with a bandgap of 1.6 eV has been demonstrated as a promising material for Pb‐free halide perovskite solar cells. Crystalline Cs2SnI6phase is obtained with CsI, SnI2, and SnF2salts in gamma‐butyrolactone solvent, but not with dimethyl sulfoxide and
- Award ID(s):
- 1665086
- NSF-PAR ID:
- 10092177
- Date Published:
- Journal Name:
- MRS Advances
- ISSN:
- 2059-8521
- Page Range / eLocation ID:
- 1 to 8
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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N,N ‐dimethylformamide solvents. Cs2SnI6is found to be stable for at least 1000 h at 100 °C when dark annealed in nitrogen atmosphere. In this study, Cs2SnI6has been used in a superstrate n–i–p planar device structure enabled by a spin‐coated absorber thickness of ≈2 μm on a chemical bath deposited Zn(O,S) electron transport layer. The best device power conversion efficiency reported here is 5.18% withV OCof 0.81 V, 9.28 mA cm−2J SC, and 68% fill factor. The dark saturation current and diode ideality factor are estimated as 1.5 × 10−3 mA cm−2and 2.18, respectively. The devices exhibit a highV OCdeficit and low short‐circuit current density due to high bulk and interface recombination. Device efficiency can be expected to increase with improvement in material and interface quality, charge transport, and device engineering. -
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1557/adv.2019.127
