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Colloidal Organometal Halide Perovskite (MAPbBr_xI_3-x, 0≤x≤3) Quantum Dots: Controllable Synthesis and Tunable Photoluminescence.

ABSTRACT: Organic-inorganic perovskite materials, typically methylammonium lead trihalide (MAPbX₃: MA = methylammonium; X = Br, I), are recently attract enormous attention for their distinguished photo-electronic properties. The control of morphology, composition and dispersability of MAPbX₃ perovskite nanocrystals is crucial for the property tailoring and still a major challenge. Here we report the synthesis of colloidal MAPbBr_xI_3-x(0 ≤ x ≤ 3) nanocrystals at room temperature by using alkyl carboxylate as capping ligands. These nanocrystals exhibit continuously tunable UV-vis absorption and photoluminescence (PL) across the visible spectrum, which is attributed to the quantum confinement effect with certain stoichiometry. Their unique exciton recombination dynamics was investigated and discussed.

SUBMITTER: Zhao Y

PROVIDER: S-EPMC5075927 | biostudies-literature |

REPOSITORIES: biostudies-literature

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