▎ 摘　　要

NOVELTY - Preparing cobalt diselenide on selenium-modified reduced graphene oxide comprises e.g. uniformly dispersing graphene oxide in distilled water under ultrasonic action to form graphene oxide aqueous solution, adding selenium dioxide into the graphene oxide aqueous solution, and reacting, adding hydrazine hydrate to mixed solution, continuing to react, cooling to room temperature, filtering black solid with suction, washing with distilled water, freeze-drying, adding selenium-modified reduced graphene oxide and cobalt chloride tetrahydrate into a beaker, adding distilled water to prepare solution A, providing predetermined amount of sodium selenite in diethylene triamine to obtain solution B, dispersing the A and B solutions separately by ultrasonic, mixing the A and B solutions into the reaction kettle, reacting, and cooling to room temperature to obtain selenium modified reduced graphene oxide supported cobalt diselenide composite material after suction filtration, cleaning and drying. USE - The preparing cobalt diselenide on selenium-modified reduced graphene oxide is useful for catalyst in the field of electrocatalysis (claimed). ADVANTAGE - The method: improves the conductivity and stability of the chalcogen compound by uniformly loading the cobalt diselenide particles of the cubic crystal system and the hexagonal crystal system in the graphene sheet layer; improves the comprehensive performance of transition metal chalcogenides; and enhances the ORR performance of the electrocatalyst. DETAILED DESCRIPTION - Preparing cobalt diselenide on selenium-modified reduced graphene oxide comprises (1) uniformly dispersing graphene oxide in distilled water under ultrasonic action to form graphene oxide aqueous solution, adding selenium dioxide into the graphene oxide aqueous solution, and reacting at a temperature of 100-150 degrees C for 2-3 hours, adding hydrazine hydrate to the mixed solution, continuing to react for 0.5-2 hours, cooling to room temperature, filtering the black solid with suction, washing with distilled water, freeze-drying, (2) adding the selenium-modified reduced graphene oxide and cobalt chloride tetrahydrate into a beaker, adding distilled water to prepare solution A, providing predetermined amount of sodium selenite in diethylene triamine to obtain solution B, dispersing the A and B solutions separately by ultrasonic, mixing the A and B solutions into the reaction kettle, reacting at 160-200 degrees C for 12-20 hours, and cooling to room temperature to obtain selenium modified reduced graphene oxide supported cobalt diselenide composite material after suction filtration, cleaning and drying. AN INDEPENDENT CLAIM is also included for composite material obtained based on the preparation method of selenium-modified reduced graphene oxide supported cobalt diselenide is composed of cobalt diselenide particles and grapheme, where the cobalt diselenide particles coexisting in the cubic and hexagonal systems are uniformly supported in the graphene sheets.