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Formamidinium Lead Bromide (FAPbBr₃) Perovskite Microcrystals for Sensitive and Fast Photodetectors.

ABSTRACT: Because of the good thermal stability and superior carrier transport characteristics of formamidinium lead trihalide perovskite HC(NH₂)₂PbX₃ (FAPbX₃), it has been considered to be a better optoelectronic material than conventional CH₃NH₃PbX₃ (MAPbX₃). Herein, we fabricated a FAPbBr₃ microcrystal-based photodetector that exhibited a good responsivity of 4000 A W^-1 and external quantum efficiency up to 10⁶% under one-photon excitation, corresponding to the detectivity greater than 10¹⁴ Jones. The responsivity is two orders of magnitude higher than that of previously reported formamidinium perovskite photodetectors. Furthermore, the FAPbBr₃ photodetector's responsivity to two-photon absorption with an 800-nm excitation source can reach 0.07 A W^-1, which is four orders of magnitude higher than that of its MAPbBr₃ counterparts. The response time of this photodetector is less than 1 ms. This study provides solid evidence that FAPbBr₃ can be an excellent candidate for highly sensitive and fast photodetectors.

SUBMITTER: Zhang F

PROVIDER: S-EPMC6199088 | biostudies-literature |

REPOSITORIES: biostudies-literature

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