Electrochemically Exfoliated Platinum Dichalcogenide Atomic Layers for High-Performance Air-Stable Infrared Photodetectors

摘要

Platinum dichalcogenide (PtX_(2)), an emergent group-10 transition metal dichalcogenide (TMD) has shown great potential in infrared photonic and optoelectronic applications due to its layer-dependent electronic structure with potentially suitable bandgap. However, a scalable synthesis of PtSe_(2) and PtTe_(2) atomic layers with controlled thickness still represents a major challenge in this field because of the strong interlayer interactions. Herein, we develop a facile cathodic exfoliation approach for the synthesis of solution-processable high-quality PtSe_(2) and PtTe_(2) atomic layers for high-performance infrared (IR) photodetection. As-exfoliated PtSe_(2) and PtTe_(2) bilayer exhibit an excellent photoresponsivity of 72 and 1620 mA W~(–1) at zero gate voltage under a 1540 nm laser illumination, respectively, approximately several orders of magnitude higher than that of the majority of IR photodetectors based on graphene, TMDs, and black phosphorus. In addition, our PtSe_(2) and PtTe_(2) bilayer device also shows a decent specific detectivity of beyond 10~(9) Jones with remarkable air-stability (>several months), outperforming the mechanically exfoliated counterparts under the laser illumination with a similar wavelength. Moreover, a high yield of PtSe_(2) and PtTe_(2) atomic layers dispersed in solution also allows for a facile fabrication of air-stable wafer-scale IR photodetector. This work demonstrates a new route for the synthesis of solution-processable layered materials with the narrow bandgap for the infrared optoelectronic applications.