▎ 摘　　要

Molybdenum disulfide (MoS2) is considered as a promising 2D material for optoelectronic applications due to its excellent electrical and optical properties. A semimetal material with zero bandgap, like graphene, can extend response range of MoS2-based photodetectors to wider spectral region. Here, a graphene/MoS2/graphene vertical heterostructure is demonstrated, where Schottky barriers are formed between MoS2 and graphenes. The introduction of graphene can effectively widen the working wavelength of the device from visible to IR range. Simultaneously, the shortened transmit distance for the photogenerated carriers between the source and drain electrodes in the vertical heterostructure leads to faster response speed compared with MoS2-based photodetectors. Besides, the graphene/MoS2/graphene photodetector shows excellent performance with an enhanced responsivity of 414 A W-1 at 532 nm and 376 A W-1 at 2000 nm, and a broad working wavelength ranging from 405 to 2000 nm. These excellent performances prove that the design of graphene based vertical heterostructure can provide new ideas for the development of high-performance photodetectors in future.