We have fabricated a novel sunlight photo-detector based on a MoS ₂ /graphene heterostructure. The MoS ₂ /graphene heterostructure was prepared by a facile hydrothermal method along with a subsequent annealing process followed by a substrate-induced high selective nucleation and growth mechanism. The microstructures and morphologies of the two-dimensional MoS ₂ /graphene heterostructure can be experimentally confirmed by x-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and a UV–vis absorption spectrometer. Photoresponse investigations performed by a photoelectrochemical (PEC) measurement system indicate that the synthesized MoS ₂ /graphene heterostructure shows superior photoresponse activities under the illumination of sunlight in contrast with bare MoS ₂ and graphene. The improved photoresponsivity can be attributed to the enhanced light absorption, strong light–matter interaction and the extremely efficient charge separation of the heterostructure. The structure and performances of the MoS ₂ /graphene heterostructure suggest promising applications in the field of photonics and optoelectronics.

Schematic illustration of the basis for the excellent electrochemical performance of the NiMoO₄@CoMoO₄nanospheres measured in an alkaline electrolyte.