Enabling Fast\nPhotoresponse in Hybrid Perovskite/MoS<sub>2</sub> Photodetectors\nby Separating Local Photocharge Generation\nand Recombination

Interfacing CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub> (MAPbI<sub>3</sub>) with 2D van der Waals materials in lateral photodetectors\ncan suppress the dark current and driving voltage, while the interlayer\ncharge separation also renders slower charge dynamics. In this work,\nwe show that more than one order of magnitude faster photoresponse\ntime can be achieved in MAPbI<sub>3</sub>/MoS<sub>2</sub> lateral\nphotodetectors by locally separating the photocharge generation and\nrecombination through a parallel channel of single-layer MAPbI<sub>3</sub>. Photocurrent (<i>I</i><sub>ph</sub>) mapping reveals\nelectron diffusion lengths of about 20 μm in single-layer MAPbI<sub>3</sub> and 4 μm in the MAPbI<sub>3</sub>/MoS<sub>2</sub> heterostructure.\nThe illumination-power scaling of <i>I</i><sub>ph</sub> and\ntime-resolved photoluminescence studies point to the dominant roles\nof the heterostructure region in photogeneration and single-layer\nMAPbI<sub>3</sub> in charge recombination. Our results shed new light\non the material design that can concurrently enhance photoresponsivity,\nreduce driving voltage, and sustain high operation speed, paving the\npath for developing high-performance lateral photodetectors based\non hybrid perovskites.