High-performance near-infrared photodetectors based on C3N quantum dots integrated with single-crystal graphene

Abstract

Quantum dots (QDs) integrated with two-dimensional (2D) nanomaterials hold potential use in photodetector devices due to the unique light absorption of QDs and excellent carrier transport properties of 2D nanomaterials. A simple strategy to fabricate hybrid graphene and QD photodetectors using a single-crystal monolayer graphene film as a carrier channel at the top and perfectly wrapping it to be in contact with the bottom layer of C₃N QDs is developed. This strategy can lead to a tight contact between C₃N QDs and the graphene interface, thus facilitating an efficient collection of all photo-generated carriers. Photodetectors, employing C₃N QDs integrated with single-crystal graphene, exhibited distinct photocurrent response with high responsivity and detectivity at 1550 nm. The photocurrent map and simulated electric field distribution reveal the fast response and recovery, indicating that C₃N QDs enhanced the local electric field near graphene. The present research indicates the strategy of combining hybrid architectures for optoelectronic devices to improve their performance thereof.