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Title: SnF 2 ‐Doped Cs 2 SnI 6 Ordered Vacancy Double Perovskite for Photovoltaic Applications
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 andN,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% withVOCof 0.81 V, 9.28 mA cm−2JSC, 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 highVOCdeficit 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.  more » « less
Award ID(s):
2046944
PAR ID:
10558932
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Solar RRL
Volume:
7
Issue:
19
ISSN:
2367-198X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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