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Dielectric Confinement and Exciton Fine Structure in Lead Halide Perovskite Nanoplatelets.

ABSTRACT: Owing to their flexible chemical synthesis and the ability to shape nanostructures, lead halide perovskites have emerged as high potential materials for optoelectronic devices. Here, we investigate the excitonic band edge states and their energies levels in colloidal inorganic lead halide nanoplatelets, particularly the influence of dielectric effects, in a thin quasi-2D system. We use a model including band offset and dielectric confinements in the presence of Coulomb interaction. Short- and long-range contributions, modified by dielectric effects, are also derived, leading to a full modelization of the exciton fine structure, in cubic, tetragonal and orthorhombic phases. The fine splitting structure, including dark and bright excitonic states, is discussed and compared to recent experimental results, showing the importance of both confinement and dielectric contributions.

SUBMITTER: Ghribi A

PROVIDER: S-EPMC8621522 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Dielectric Confinement and Exciton Fine Structure in Lead Halide Perovskite Nanoplatelets.

Ghribi Amal A Ben Aich Rim R Boujdaria Kaïs K Barisien Thierry T Legrand Laurent L Chamarro Maria M Testelin Christophe C

Nanomaterials (Basel, Switzerland) 20211113 11

Owing to their flexible chemical synthesis and the ability to shape nanostructures, lead halide perovskites have emerged as high potential materials for optoelectronic devices. Here, we investigate the excitonic band edge states and their energies levels in colloidal inorganic lead halide nanoplatelets, particularly the influence of dielectric effects, in a thin quasi-2D system. We use a model including band offset and dielectric confinements in the presence of Coulomb interaction. Short- and lo ...[more]

PMID: 34835818

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