Boosting Optoelectronic Properties in Mixed 2D/3D Metal Halide Perovskite Films for Light-Emitting Diodes
발표자
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초록
내용
Although numerous successful empirical results have been obtained for mixed two-dimensional (2D)/three-dimensional (3D) perovskite films, the nature of charge carriers in correlation with the crystallographic properties and composition of the films remains elusive. Herein, we investigated the nature of charge carriers and its impact on the luminescence and transport behaviors in a mixed 2D/3D perovskite system containing 2D butylammonium lead bromide (BA2PbBr4) and 3D formamidinium lead bromide (FAPbBr3). Ultrafast transient absorption and temperature-dependent photoluminescence measurements revealed distinct changes in both the electron–hole and electron–phonon coupling behaviors, which critically determined nonemissive decay processes of the excited states, including the hot carriers. These behaviors could then be closely correlated with the crystallographic evolution of the perovskite films.