Investigation on the Strong Light-Matter Interaction in the Graphene-Perovskite Heterostructure Photodetector

摘要

Two-dimensional perovskite materials have received wide interests due to their highly impressive optoelectronic properties. The combination of single crystalline perovskite as thin as several unit cells with graphene has not been demonstrated, which may have some outstanding performance for its high crystallinity and less defects. Here, high-quality 2D perovskite crystals as thin as several unit cells are synthesized and a broadband photodetector with a high on/off ratio of 4.28x10~3 is demonstrated. Based on this, we further fabricated a novel hybrid photodetector by growing single crystalline 2D CH3NH3PbI3 perovskite directly onto the graphene channel, and the resulting device shows an impressive photoresponsivity of 61.2 A/W that is six orders of magnitude over pristine perovskite photodetector. Also, a much faster response time of 130 ms is observed, which takes only one-tenth the response time of pristine perovskite photodetector. These results show that 2D graphene-perovskite heterostructure can be a promising candidate for highly efficient and low-cost optoelectronic applications.