Revealing Excitonic Phonon Coupling in (PEA)2(MA)n−1PbnI3n+1 2D Layered Perovskites

• DOI: 10.1021/acs.jpclett.0c01714
• Publication Date: 2020-06-29T05:48:52Z
• Authors: Joanna M. Urban; Gabriel Chehade; Mateusz Dyksik; Matan Menahem; Alessandro Surrente; Gaëlle Trippé-Allard; Duncan K. Maude; Damien Garrot; Omer Yaffe; Emmanuelle Deleporte; Paulina Plochocka; Michal Baranowski
• Keywords: [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry; 500; Metal halide perovskites, exciton-phonon coupling, magneto optical spectroscopy; [CHIM.MATE]Chemical Sciences/Material chemistry; 530; 01 natural sciences; 0104 chemical sciences

The family of 2D Ruddlesden–Popper perovskites is currently attracting great interest the scientific community as highly promising materials for energy harvesting and light emission applications. Despite fact that these are known decades, only recently has it become apparent their optical properties driven by exciton–phonon coupling, which controlled organic spacers. However, detailed mechanism this gives rise to complex absorption spectra, subject ongoing controversy. In work we show particularly rich, spectra (PEA)2(CH3NH3)n−1PbnI3n+1 (where PEA stands phenylethylammonium n = 1, 2, 3), related a vibronic progression excitonic transition. contrast other two-dimensional perovskites, observe coupling high-energy (40 meV) phonon mode probably torsional motion NH3+ head spacer.