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Plurality of excitons in Ruddlesden-Popper metal halides and the role of the B-site metal cation.

ABSTRACT: We investigate the effect of metal cation substition on the excitonic structure and dynamics in a prototypical Ruddlesden-Popper metal halide. Through an in-depth spectroscopic and theoretical analysis, we identify the presence of multiple resonances in the optical spectra of a phenethyl ammonium tin iodide, a tin-based RPMH. Based on ab initio calculations, we assign these resonances to distinct exciton series that originate from the splitting of the conduction band due to spin-orbit coupling. While the splitting energy in the tin based system is low enough to enable the observation of the higher lying exciton in the visible-range spectrum of the material, the higher splitting energy in the lead counterpart prevents the emergence of such a feature. We elucidate the critical role played by the higher lying excitonic state in the ultrafast carrier thermalization dynamics.

SUBMITTER: Folpini G

PROVIDER: S-EPMC10068426 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Plurality of excitons in Ruddlesden-Popper metal halides and the role of the B-site metal cation.

Folpini Giulia G Palummo Maurizia M Cortecchia Daniele D Moretti Luca L Cerullo Giulio G Petrozza Annamaria A Giorgi Giacomo G Srimath Kandada Ajay Ram AR

Materials advances 20230307 7

We investigate the effect of metal cation substition on the excitonic structure and dynamics in a prototypical Ruddlesden-Popper metal halide. Through an in-depth spectroscopic and theoretical analysis, we identify the presence of multiple resonances in the optical spectra of a phenethyl ammonium tin iodide, a tin-based RPMH. Based on <i>ab initio</i> calculations, we assign these resonances to distinct exciton series that originate from the splitting of the conduction band due to spin-orbit cou ...[more]

PMID: 37026040

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