2024-10-11 ノースカロライナ州立大学(NCState)
＜関連情報＞
- https://news.ncsu.edu/2024/10/engineering-layered-hybrid-perovskites/
- https://www.cell.com/matter/abstract/S2590-2385(24)00489-2
カチオンライゲーションが層状ハイブリッドペロブスカイトの量子井戸形成を導く Cationic ligation guides quantum-well formation in layered hybrid perovskites
Kasra Darabi∙ Mihirsinh Chauhan∙ Boyu Guo∙ … ∙ Milad Abolhasani∙ Kenan Gundogdu∙ Aram Amassian
Matter Published:October 11, 2024
DOI:https://doi.org/10.1016/j.matt.2024.09.010
Graphical abstract
Progress and potential
Layered hybrid perovskites require size-tunable and oriented quantum wells (QWs) to achieve energy funneling for light emission applications, such as LEDs and lasers. We have discovered that nanoplatelets (NPLs) that spontaneously form during synthesis are photoactive and form intermediate size QWs. We also show that the size and orientation of NPLs can be controlled through anti-solvent processing, which helps engineer QW energy cascades. NPLs undergo ripening that is detectable in situ by optical diagnostics, thereby enabling process monitoring and control. We time the antisolvent drip with the NPL ripening to control QW size distribution. This enables energy cascade engineering essential for demonstration of amplified emission with low threshold, high reproducibility, and ambient photostability. We also leverage NPLs to control the facet orientation of 3D perovskites and enhance efficiency and stability of wide-bandgap solar cells.
Highlights
•Nanoplatelets (NPLs) form early by bulky cations acting like crystal-terminating ligands
•Photoactive NPLs ripen, forming 3D-like textured skin and tuning QW size distribution
•QW size distribution, orientation, and energy cascades controlled by antisolvent drip
•Amplified emission with reduced threshold, reproducibility, and stability demonstrated
Summary
Layered hybrid perovskites (LHPs) have emerged as promising reduced-dimensional semiconductors for next-generation photonic and energy applications, wherein controlling the size, orientation, and distribution of quantum wells (QWs) is of paramount importance. Here, we reveal that bulky molecular spacers act as crystal-terminating ligands to form colloidal nanoplatelets (NPLs) during early stages of LHP formation. NPLs template the crystallization of LHPs. Using multi-modal diagnostics, we prove that NPLs ripen and grow, playing a decisive role in the time evolution of QW size, population distribution, and orientation. We demonstrate antisolvent drip interrupts NPL ripening and thereby controls QW orientation, population, and energy cascades within LHP films. Using this approach, we achieve low-threshold amplified emission (AE) with remarkable reproducibility. We further introduce synthesized NPLs in the antisolvent step of 3D perovskites to control facet orientation and achieve enhanced efficiency and stability in wide-bandgap solar-cell devices compared to untextured controls.
