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Optical and Structural Property Tuning in Physical Vapor Deposited Bismuth Halides Cs₃Bi₂(I_1-xBr_x)₉ (0 ≤ x ≤ 1).

ABSTRACT: Crystalline films of lead-free all-inorganic Cs₃Bi₂X₉ (X = Br, I) perovskites have been deposited by radio frequency (RF)-magnetron sputtering providing high-quality, single-phase films as confirmed by structural, morphological, and optical property characterization. Progressive tuning of crystal structure characteristics and optical absorbance has been achieved in mixed Br/I phases Cs₃Bi₂(I_1-xBr_x)₉ (0 ≤ x ≤ 1), highlighting a shift of the band gap from about 2.0 eV for Cs₃Bi₂I₉ to 2.64 eV for Cs₃Bi₂Br₉. X-ray diffraction and Raman scattering allowed defining the range of alloyed compositions where single-phase compositions are found. Finally, preliminary photocatalytic activity tests on the degradation of methylene blue provided solid data indicating the future possible exploitation of Bi-based perovskite derivative materials as active photocatalysts.

SUBMITTER: Bonomi S

PROVIDER: S-EPMC8456412 | biostudies-literature |

REPOSITORIES: biostudies-literature

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