Ternary ZnXCd1-XS particles were directly immobilized on graphene sheets by a facile solvothermal route with zinc acetate, cadmium acetate and thiourea as precursors, ethylene glycol as reaction solvent and graphene oxide as support. The value of x could be adjusted by controlling the molar ratio of Zn and Cd precursors. The products were characterized by X-ray diffraction, scanning electron microscope and ultraviolet-visible absorption. The photoelectric properties of the graphene-ZnXCd1-XS composites were investigated by transient photocurrent responses and electrochemical impedance spectra, and the results show that the obvious increase in the photocurrent density and decrease in electron-transfer resistance can be seen for graphene-Zn0.8Cd0.2S composites as compared to graphene-ZnXCd1-XS composites with other Zn/Cd ratios. (C) 2015 Elsevier B.V. All rights reserved.