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Title: Engineering ligand reactivity enables high-temperature operation of stable perovskite solar cells
Perovskite solar cells (PSCs) consisting of interfacial two- and three-dimensional heterostructures that incorporate ammonium ligand intercalation have enabled rapid progress toward the goal of uniting performance with stability. However, as the field continues to seek ever-higher durability, additional tools that avoid progressive ligand intercalation are needed to minimize degradation at high temperatures. We used ammonium ligands that are nonreactive with the bulk of perovskites and investigated a library that varies ligand molecular structure systematically. We found that fluorinated aniliniums offer interfacial passivation and simultaneously minimize reactivity with perovskites. Using this approach, we report a certified quasi–steady-state power-conversion efficiency of 24.09% for inverted-structure PSCs. In an encapsulated device operating at 85°C and 50% relative humidity, we document a 1560-hourT85at maximum power point under 1-sun illumination.  more » « less
Award ID(s):
1936527
NSF-PAR ID:
10491520
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; « less
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science
Volume:
381
Issue:
6654
ISSN:
0036-8075
Page Range / eLocation ID:
209 to 215
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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