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Mechanical failure and chemical degradation of device heterointerfaces can strongly influence the long-term stability of perovskite solar cells (PSCs) under thermal cycling and damp heat conditions. We report chirality-mediated interfaces based onR-/S-methylbenzyl-ammonium between the perovskite absorber and electron-transport layer to create an elastic yet strong heterointerface with increased mechanical reliability. This interface harnesses enantiomer-controlled entropy to enhance tolerance to thermal cycling–induced fatigue and material degradation, and a heterochiral arrangement of organic cations leads to closer packing of benzene rings, which enhances chemical stability and charge transfer. The encapsulated PSCs showed retentions of 92% of power-conversion efficiency under a thermal cycling test (−40°C to 85°C; 200 cycles over 1200 hours) and 92% under a damp heat test (85% relative humidity; 85°C; 600 hours).
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This content will become publicly available on June 11, 2026
Ability of strained C atoms to act as an electron donor
Strong negative charge on the tetravalent apical C of propellane can attract an electrophile, which can then extract charge from the prominent lobe of its C–C bonding orbital, to form a strong noncovalent bond with C as an electron donor.
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- Award ID(s):
- 1954310
- PAR ID:
- 10624165
- Publisher / Repository:
- ce
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 16
- Issue:
- 23
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 10572 to 10584
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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