Ag nanoparticles enhanced PbS QDs/graphene/Si near-infrared photodetector

This paper introduces a PbS quantum dots (QDs)/graphene/Si near-infrared (NIR) photodetector. The excellent infrared sensitivity of PbS QDs enables the device to work in the near-infrared band. At the same time, the high mobility of graphene to carriers also improves the performance of the device. The local electric field is enhanced by spin-coating a layer of silver nanoparticles (Ag NPs) on the surface of the device, thereby increasing the photocurrent of the device. The addition of silver nanoparticles improves the performance of PbS QDs/graphene/Si near-infrared photodetectors, and the photodetector has a high responsivity of 0.15 A/W for 1550 nm incident light. Under high-frequency illumination, there is still a good response time. This high-performance PbS QDs/graphene/Si structure photodetector can be widely used in near-infrared photodetection.