▎ 摘　　要

NOVELTY - Cobalt sulfide/multilayer graphene composite material comprises cobalt sulfide uniformly distributed on the surface of the multilayer graphene, where cobalt sulfide has a nanosheet structure and the nanosheets cross each other into small clusters and grow on the surface of the multilayer graphene. USE - As cobalt sulfide/multilayer graphene composite material. ADVANTAGE - The composite material adopts simple preparation method which can prepare the metal sulfide on the surface of the multilayer graphene without active functional groups in one step and is suitable for large-scale production. DETAILED DESCRIPTION - Cobalt sulfide/multilayer graphene composite material comprises cobalt sulfide of formula: Co3S4 uniformly distributed on the surface of the multilayer graphene, where cobalt sulfide has a nanosheet structure and the nanosheets cross each other into small clusters and grow on the surface of the multilayer graphene. An INDEPENDENT CLAIM is included for a method for preparing the composite material involving (i) using dimethylformamide (DMF) and distilled water in a volume ratio of 8:2, mixing as a mixed solvent, where the both volume is used as the volume of the mixed solvent for calculation, (ii) adding expanded graphite and performing ultrasonic oscillation to obtain a multilayer graphene solution, (iii) adding cobalt acetate tetrahydrate and thiourea to the multilayer graphene solution, where the addition amount of cobalt acetate tetrahydrate is 8-12 mg/ml, the addition amount of thiourea is 2.44-3.66 mg/ml and the molar concentration ratio of cobalt ions and sulfur ions is 1:0.8-1:1, pouring into a hydrothermal reaction kettle, maintaining the temperature at 150-170 degrees C for 12 hours and cooling to room temperature and (iv) taking out a reaction product, centrifugally washing with alcohol and water and drying in a drying oven at 60 degrees C for 24 hours to obtain the dried composite material.