Direct Growth of van der Waals Graphene/MAPbI₃ Heterojunction for Wide Spectral Photodetection

Here, we demonstrate a high-performance photodetector for wide spectral detection (405 nm-808 nm). The device is based on 2D/3D van der Waals heterojunction (vHJ) by directly integrating MAPbI3 single crystal (SC) onto monolayer graphene with a developed inverse temperature crystallization method (DITC). The proposed photodetector exhibits a high responsivity of 1.45 A/W, an excellent detectivity of
${6}.{67} \times {10} ^{{12}}$
Jones, an impressive on/off ratio of nearly
$10^{{4}}$
. Moreover, the fabricated device also shows an excellent self-powered behavior with a high 3-dB bandwidth of 3.5 kHz, and a fast rise/fall time of
$69 \, \mu \text{s}/138 \, \mu \text{s}$
. Our work provides a novel insight for the design of high-performance photodetector based on 2D/3D vHJ.