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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 March 1, 2026
Pressure Engineering to Enable Improved Stability and Performance of Metal Halide Perovskite Photovoltaics
In this work, we demonstrate that an external pressure of 15–30 kPa can significantly improve metal halide perovskite (MHP) film thermal stability. We demonstrate this through the application of weight on top of an MHP film during thermal aging in preserving the perovskite phase and the mobile ion concentration, an effect which we hypothesize reduces the extent to which volatile species can escape from the MHP lattice. This method is shown to be effective for a more scalable approach by only applying the weight to a cover glass during the lamination of an epoxy-based resin, after which the weight is removed. The amount of pressure applied during lamination is shown to correlate with stability in both 1 sun illumination and damp heat testing. Lastly, the performance of MHP photovoltaic devices is improved using pressure during lamination, an effect which is attributed to improved interfacial contact between the MHP and the adjacent charge transport layers and healing of any voids or defects that may exist at the buried interface after processing. As such, there are implications for tuning the amount of pressure that is applied during lamination to enable the durability of MHP solar modules toward manufacturing-scale deployment.
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- Award ID(s):
- 2339233
- PAR ID:
- 10592221
- Publisher / Repository:
- Molecules
- Date Published:
- Journal Name:
- Molecules
- Volume:
- 30
- Issue:
- 6
- ISSN:
- 1420-3049
- Page Range / eLocation ID:
- 1292
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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