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CsPbBr₃ Perovskite Powder, a Robust and Mass-Producible Single-Source Precursor: Synthesis, Characterization, and Optoelectronic Applications.

ABSTRACT: A facile synthesis method is proposed for the mass production of high-quality CsPbBr₃ perovskite powder. It is shown that the proposed synthesis protocol is capable of producing polycrystalline CsPbBr₃ powder in quantities greater than 10 g. The derived thin films by thermal evaporation and spin-coating are of compact morphologies (root-mean-square roughness < 4 nm) without voids and pinholes. Moreover, the thin films show obvious photoluminescence (PL) with a narrow (bandwidth < 19 nm) peak centered at ∼520 nm, which is blue-shifted compared with the PL emission of the powder at 542 nm. The powder and the spin-coated film exhibit superior PL stability under long-term ambient conditions and in thermal cycling experiments performed at temperatures up to ∼120 °C. Accordingly, optoelectronic applications including the fabrication and characteristics of the electroluminescence device, the organic-inorganic powder doped with methylammonium and formamidinium ions, and fluorescent greenish-blue quantum dots are also demonstrated. On the basis of these demonstrations, the synthesized CsPbBr₃ perovskite powder can be expected to empower the advances in perovskite-related optoelectronics in the future.

SUBMITTER: Huang CY

PROVIDER: S-EPMC6647985 | biostudies-literature |

REPOSITORIES: biostudies-literature

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