High-Performance Near-Infrared Photodetector by Integration of PbS Quantum Dots With 3D-Graphene

Achieving breakthroughs in high-performance near-infrared (NIR) photodetectors (PDs) relies on selecting materials and designing device structures. This work shows the synergistic effect between three-dimensional graphene (3D-graphene) and PbS quantum dots (PbS QDs) in the PD structure design, achieved by in-situ growth of 3D-graphene on the silicon (Si) substrate, followed by PbS QDs modification on the 3D-graphene surface. The high-performance NIR PD based on PbS QDs/3D-graphene/Si heterojunction is realized. The synergistic effect of 3D-graphene with strong light absorption and the effective built-in potential modulation by PbS QDs lead to the high detectivity ( $1\times 10^{{11}}$ Jones) and responsivity (13.7 A/W) of the as-fabricated PD at 1550 nm.