▎ 摘　　要

NOVELTY - A graphene-based cadmium sulfide composite material preparing method involves preparing graphene oxide solution, dissolving cadmium chloride in super-pure water, adding graphene oxide solution to mixture, stirring mixture to make cadmium dications adsorb on graphene oxide surface, adding sodium thiosulfate pentahydrate to mixture, and stirring the mixture, where the positively charged cadmium cations attract negatively charged thiosulfate anions. The mixture is reacted in a hydrothermal reaction kettle and cooled followed by filtering mixture, washing mixture and vacuum-drying mixture. USE - Method for preparing a graphene-based cadmium sulfide composite material that is utilized in electrochemical detection of trace hydrogen peroxide-free enzyme assay material. ADVANTAGE - The method enables preparing the graphene-based cadmium sulfide composite material in an inexpensive and simple manner with high stability. DETAILED DESCRIPTION - A graphene-based cadmium sulfide composite material preparing method involves preparing graphene oxide solution, dissolving 0.1142 g cadmium chloride in 75 ml super-pure water, adding 15 ml graphene oxide solution to the mixture, stirring the mixture magnetically for 30 minutes to make cadmium dications adsorb on graphene oxide surface, adding 0.1241 g sodium thiosulfate pentahydrate to the mixture and stirring the mixture continuously for 15 minutes, where the positively charged cadmium cations attract negatively charged thiosulfate anions. The obtained mixture is mixed in a hydrothermal reaction kettle and reacted at 160 degrees C at constant temperature. The kettle is cooled naturally followed by filtering the mixture, washing the mixture for 3 times and vacuum-drying the mixture to obtain reduced graphene oxide-cadmium sulfide (RGO-CdS) composite material.