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Title: Two-dimensional perovskite templates for durable, efficient formamidinium perovskite solar cells
We present a design strategy for fabricating ultrastable phase-pure films of formamidinium lead iodide (FAPbI3) by lattice templating using specific two-dimensional (2D) perovskites with FA as the cage cation. When a pure FAPbI3precursor solution is brought in contact with the 2D perovskite, the black phase forms preferentially at 100°C, much lower than the standard FAPbI3annealing temperature of 150°C. X-ray diffraction and optical spectroscopy suggest that the resulting FAPbI3film compresses slightly to acquire the (011) interplanar distances of the 2D perovskite seed. The 2D-templated bulk FAPbI3films exhibited an efficiency of 24.1% in a p-i-n architecture with 0.5–square centimeter active area and an exceptional durability, retaining 97% of their initial efficiency after 1000 hours under 85°C and maximum power point tracking.  more » « less
Award ID(s):
1848371
PAR ID:
10643120
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  more » ;  ;  ;  ;  ;   « less
Publisher / Repository:
Science
Date Published:
Journal Name:
Science
Volume:
384
Issue:
6701
ISSN:
0036-8075
Page Range / eLocation ID:
1227 to 1235
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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