上海科技大学知识管理系统

2D hybrid perovskites have shown great promise in the photodetection field,
due to their intriguing attributes stemming from unique structural architectures.
However, the great majority of detectors based on this 2D system
possess a relatively low response speed (≈ms), making it extremely urgent to
develop new candidates for superfast photodetection. Here, a new organic–
inorganic hybrid perovskite, (PA)2(FA)Pb2I7 (EFA, where PA is n-pentylaminium
and FA is formamidine), which features the 2D Ruddlesden–Popper
type perovskite framework that is composed of the corner-sharing PbI6 octahedra
is reported. Significantly, photodetectors fabricated on highly oriented
thin films, which exhibit a perfect orientation parallel to 2D inorganic perovskite
layers, exhibit a superfast response time up to ≈2.54 ns. To the best of
the knowledge, this figure-of-merit catches up with that of the top-ranking
commercial materials, and sets a new record for 2D hybrid perovskite photodetectors.
Moreover, extremely high photodetectivity (≈1.73 × 1014 Jones,
under an incident power intensity of ≈46 μW cm−2), considerable switching
ratios (>103), and low dark current (≈10 pA) are also achieved in the detector,
indicating its great potential for high-efficiency photodetection. These results
shed light on the possibilities to explore new 2D candidates for assembling
future high-performance optoelectronic devices.