Exciton Properties and Broadband Emission in Two-Dimensional Ruddlesden–Popper Perovskites

Tan J., Jiang X., Liu D., Tang Z., Chulkov E., Vasenko A. S.

Journal of Physical Chemistry Letters, vol.16, no.30, pp.7659-7665, 2025 (SCI-Expanded, Scopus) identifier identifier

  • Nəşrin Növü: Article / Article
  • Cild: 16 Say: 30
  • Nəşr tarixi: 2025
  • Doi nömrəsi: 10.1021/acs.jpclett.5c01958
  • jurnalın adı: Journal of Physical Chemistry Letters
  • Jurnalın baxıldığı indekslər: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Compendex, MEDLINE, Nature Index
  • Səhifə sayı: pp.7659-7665
  • Açıq Arxiv Kolleksiyası: Məqalə
  • Adres: Bəli

Qısa məlumat

Two-dimensional (2D) Ruddlesden–Popper (RP) perovskites are considered as promising optoelectronic materials due to their intriguing broadband emission properties. However, the origin of the broadband emission in RP perovskites remains a controversial issue. Herein, we have systematically analyzed the exciton behavior and luminescence properties of 2D (PEA)2PbI4. Our calculations demonstrate that 2D (PEA)2PbI4exhibits significant quantum confinement effects, which provide a prerequisite for the formation of self-trapped excitons (STEs). However, the intrinsic STEs are absent in pristine lattices. In contrast, the iodine vacancy (VI1) is energetically favorable and exhibits a shallow charge transition level above the valence band maximum at ∼2.17 eV, which further induces large lattice deformation around the defect to accommodate STEs. Further excited-state electronic structure calculations strongly suggest that the VI1-associated extrinsic STEs are responsible for the broadband emission in 2D (PEA)2PbI4. This mechanistic understanding of exciton properties provides fundamental design principles for high-efficiency light-emitting diodes.