High-performance broadband flexible photodetector based on Gd3Fe5O12-assisted double van der Waals heterojunctions

Flexible photodetectors are fundamental elements to develop wearable systems, which can be widely used for in medical detection, environmental monitoring and flexible imaging, etc. However, compared with 3D materials, the degraded performance based on low dimensional materials remains a key challenge for current flexible photodetectors. Here, a broadband photoresponse flexible photodetector with high performance has been proposed and fabricated. By combining the high mobility of graphene (Gr) with the strong light–matter interactions of single-walled carbon nanotubes (SWCNT) and molybdenum disulfide (MoS 2 ), the flexible photodetector exhibits a greatly improved photoresponse performance covering visible to near-infrared range. Additionally, the thin layer of gadolinium iron garnet (Gd 3 Fe 5 O 12 , GdlG) films are introduced to improve the interface of the double van der Waals heterojunctions to reduce the dark current. The SWCNT/GdIG/Gr/GdIG/MoS 2 flexible photodetector exhibits a high photoresponsivity of 47.375 A/W and a high detectivity of 1.952×10 12 Jones at 450nm, 109.311 A/W and a high detectivity of 4.504×10 12 Jones at 1080nm, with good mechanical stability at room temperature. This work demonstrates the good capacity of GdIG-assisted double van der Waals heterojunctions on flexible substrates and provides a new solution for preparing high-performance flexible photodetectors.