Organic Cation Dynamics in the Layered Lead Iodide Perovskites BA₂PbI₄ and PEA₂PbI₄.

ABSTRACT: We report on a quasielastic neutron scattering (QENS) study of the rotational dynamics of organic cations in the optoelectronic layered metal halide perovskites BA₂PbI₄ (BA = butylammonium, CH₃(CH₂)₃NH₃) and PEA₂PbI₄ (PEA = phenethylammonium, C₆H₅(CH₂)₂NH₃). For BA₂PbI₄, the measurements reveal highly temperature dependent dynamics. Between 100 and 260 K, the dynamics are ascribed to rotational dynamics of the -CH₃ and -NH₃ groups of the BA cation, whereas above 300 K we also observe the additional presence of full rotations of the whole BA cation around its long molecular axis. For PEA₂PbI

SUBMITTER: Laven R 

PROVIDER: S-EPMC12516723 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature