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Hybrid perovskite materials have emerged as excellent candidates for next-generation optoelectronic applications. Nevertheless, many vapor deposition techniques face challenges like phase segregation, thermal decomposition, and nonstoichiometric film growth. Resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) addresses these challenges by eliminating thermal stability concerns for precursor materials while maintaining stoichiometry and producing high-quality film growth. Despite its advantages, scaling up RIR-MAPLE remains underexplored compared to conventional techniques. A main challenge is to ensure high throughput with precise control over film properties. RIR-MAPLE films are typically grown under an active vacuum (chamber pressure of ∼10−5 Torr). Film deposition under background gas pressure has not been investigated, leaving questions about how an inert gas environment could influence material properties. Thus, understanding film deposition in a reduced vacuum environment with background inert gas, such as nitrogen gas, is crucial to demonstrate the feasibility of higher throughput to achieve industrial scalability. This study examines the effect of nitrogen background pressure on the deposition of two-dimensional hybrid perovskite films, namely, phenethylammonium lead iodide revealing significant improvements in film crystallinity, optical properties, and defect density with increasing background pressure, thereby highlighting the potential for scaling RIR-MAPLE for the synthesis of high-performance hybrid perovskite films.
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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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