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Two-Dimensional Perovskite (PEA)₂PbI₄ Two-Color Blue-Green Photodetector.

ABSTRACT: Perovskite materials have been widely used to fabricate solar cells, laser diodes and other photodevices, owing to the advantage of high absorption coefficient, long carrier life and shallow defect energy levels. However, due to easy hydrolysis, it is difficult to fabricate perovskite micro-nano devices. Herein, we developed a water-free device fabrication technology and fabricated a two-dimensional (C₆H₅C₂H₄NH₃)₂PbI₄ ((PEA)₂PbI₄) two-color blue-green light detector, which exhibits high detection performance under the illumination of two-color lasers (λ = 460 nm, 532 nm). Compared with bulk devices, the dark current of the fabricated devices (10^-11 A) was reduced by 2 orders of magnitude. The peak responsivity and detectivity are about 1 A/W and 10¹¹ Jones, respectively. The photodetection performance of the device is basically the same under the two-color lasers. Our results provide a new process to fabricate perovskite microelectronic devices, and the fabricated photodetector shows great application prospects in underwater detection, owing to the blue-green window existing in water.

SUBMITTER: Dou W

PROVIDER: S-EPMC9331230 | biostudies-literature |

REPOSITORIES: biostudies-literature

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