Abstract Two key interfaces in flexible perovskite solar cells (f‐PSCs) are mechanically reinforced simultaneously: one between the electron‐transport layer (ETL) and the 3D metal‐halide perovskite (MHP) thin film using self‐assembled monolayer (SAM), and the other between the 3D‐MHP thin film and the hole‐transport layer (HTL) using an in situ grown low‐dimensional (LD) MHP capping layer. The interfacial mechanical properties are measured and modeled. This rational interface engineering results in the enhancement of not only the mechanical properties of both interfaces but also their optoelectronic properties holistically. As a result, the new class of dual‐interface‐reinforced f‐PSCs has an unprecedented combination of the following three important performance parameters: high power‐conversion efficiency (PCE) of 21.03% (with reduced hysteresis), improved operational stability of 1000 hT90(duration at 90% initial PCE retained), and enhanced mechanical reliability of 10 000 cyclesn88(number of bending cycles at 88% initial PCE retained). The scientific underpinnings of these synergistic enhancements are elucidated.
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This content will become publicly available on August 14, 2026
Multifunction Hydrophobic Ligand Engineered Cd(S, Se)/ZnS Quantum Dots for Stabilizing Highly Efficient Carbon‐Based Perovskite Solar Cells
Abstract The long‐term operational stability of perovskite solar cells (PSCs) remains a key challenge impeding their commercialization, particularly due to ambient environments (e.g., moisture, oxygen, heat)‐induced degradation. Carbon electrode‐based PSCs have emerged as cost‐effective and relatively stable alternatives to metal electrode‐based devices due to carbon materials' hydrophobic behavior, yet they still lag in both long‐term durability and power conversion efficiency (PCE). In this work, an ultrathin hydrophobic ligand‐modified core–shell Cd(S,Se)/ZnS quantum dots (QDs) capping layer is introduced as a multifunctional interfacial modifier for carbon‐electrode‐based PSCs. This oleic acid ligand‐modified QDs capping layer exhibits inherent hydrophobicity, effectively serving as a moisture barrier to retard perovskite degradation under ambient conditions. Furthermore, the strong interfacial bonding between the QDs and perovskite halide surfaces leads to efficient trap state passivation, reducing trap density and creating a more uniform electrical contact. The modified QDs/perovskite interface also features an elevated conduction band edge, promoting improved charge extraction. As a result, devices incorporating this quantum dot capping layer retain 98% of their initial PCE after 450 h of ambient aging and achieve a champion efficiency of 20.74%. This strategy highlights the potential of hydrophobic ligand‐modified chalcogenide QDs as surface modifiers to enhance both the stability and performance of carbon‐based PSCs, offering a promising route toward scalable fabrication of durable perovskite solar modules.
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- Award ID(s):
- 2330738
- PAR ID:
- 10640281
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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