High-performance photodetectors require efficient photogeneration and charge transport. Perovskite quantum dots (PQDs) have received enormous interest for applications in optoelectronics due to their high photogeneration efficiency. However, they offer meager carrier transport. Reduced graphene oxide (RGO) exhibits inferior photoresponse compared to materials such as quantum dots. An effective synthesis protocol to grow PQDs from the RGO lattice may facilitate direct charge transfers from PQDs to RGO, which could not be accomplished by mixing individual PQDs with RGO or making a bilayer. At ambient condition, the photodetector fabricated with the PQD-RGO superstructure showed high responsivity of 1.07 × 103 A/W, detectivity of 1 × 1013 Jones as well as sharp switching in the visible wavelength. After 3 months in an unencapsulated sample, the photocurrent was decreased ∼10% of its initial value while preserving speed and cycle stability at ambient condition.
Keywords: charge transfer; fast photoresponse; graphene; perovskite; perovskite quantum dot; photodetector; reduced graphene oxide; superstructure.