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Abstract The combined effects of compact TiO2(c‐TiO2) electron‐transport layer (ETL) are investigated without and with mesoscopic TiO2(m‐TiO2) on top, and without and with an iodine‐terminated silane self‐assembled monolayer (SAM), on the mechanical behavior, opto–electronic properties, photovoltaic (PV) performance, and operational‐stability of solar cells based on metal‐halide perovskites (MHPs). The interfacial toughness increases almost threefold in going from c‐TiO2without SAM to m‐TiO2with SAM. This is attributed to the synergistic effect of the m‐TiO2/MHP nanocomposite at the interface and the enhanced adhesion afforded by the iodine‐terminated silane SAM. The combination of m‐TiO2and SAM also offers a significant beneficial effect on the photocarriers extraction at the ETL/MHP interface, resulting in perovskite solar cells (PSCs) with power‐conversion efficiency (PCE) of over 24% and 20% for 0.1 and 1 cm2active areas, respectively. These PSCs also have exceptionally long operational‐stability lives: extrapolatedT80 (duration at 80% initial PCE retained) is ≈18 000 and 10 000 h for 0.1 and 1 cm2active areas, respectively.Postmortemcharacterization and analyses of the operational‐stability‐tested PSCs are performed to elucidate the possible mechanisms responsible for the long operational‐stability.
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This content will become publicly available on April 17, 2026
C 60 -based ionic salt electron shuttle for high-performance inverted perovskite solar modules
Although C60is usually the electron transport layer (ETL) in inverted perovskite solar cells, its molecular nature of C60leads to weak interfaces that lead to non-ideal interfacial electronic and mechanical degradation. Here, we synthesized an ionic salt from C60, 4-(1',5′-dihydro-1'-methyl-2'H-[5,6] fullereno-C60-Ih-[1,9-c]pyrrol-2'-yl) phenylmethanaminium chloride (CPMAC), and used it as the electron shuttle in inverted PSCs. The CH2-NH3+head group in the CPMA cation improved the ETL interface and the ionic nature enhanced the packing, leading to ~3-fold increase in the interfacial toughness compared to C60. Using CPMAC, we obtained ~26% power conversion efficiencies (PCEs) with ~2% degradation after 2,100 hours of 1-sun operation at 65°C. For minimodules (four subcells, 6 centimeters square), we achieved the PCE of ~23% with <9% degradation after 2,200 hours of operation at 55°C.
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- Award ID(s):
- 2339233
- PAR ID:
- 10592220
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Science
- Date Published:
- Journal Name:
- Science
- ISSN:
- 0036-8075
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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