▎ 摘　　要

NOVELTY - Preparation of graphene quantum dot-doped carbon-coated sulfur micro material involves heating citric acid, adding deionized water, adding sodium hydroxide solution to adjust pH, adding graphene oxide, ultrasonically dispersing, obtaining black solution, dissolving solid sodium thiosulfate and polyethylene glycol 4000 in deionized water, heating, adding concentrated hydrochloric acid and black solution, reacting, obtaining black solid, dissolving sucrose in deionized water, adding black solid, ultrasonically dispersing, adding concentrated sulfuric acid, stirring, and centrifuging. USE - Preparation of graphene quantum dot-doped carbon-coated sulfur micro material (claimed). ADVANTAGE - The method enables economical preparation of graphene quantum dot-doped carbon-coated sulfur micro material by simple process. DETAILED DESCRIPTION - Preparation of graphene quantum dot-doped carbon-coated sulfur micro material involves heating citric acid at 150-250 degrees C for 1-10 minutes, adding deionized water in an amount of 1-5 times of citric acid solution, adding 0.5-2 mol/L sodium hydroxide solution to adjust pH to 5-9, adding graphene oxide to obtained clear orange solution of graphene quantum dots, ultrasonically dispersing, obtaining black solution, dissolving solid sodium thiosulfate and polyethylene glycol 4000 in deionized water, heating to 50-100 degrees C, adding concentrated hydrochloric acid and black solution, stirring for 2-10 minutes, reacting for 5-15 minutes, cooling reaction mixture to room temperature, centrifuging at 5000-10000 rpm for 60-180 seconds, obtaining a black solid, dissolving sucrose in deionized water, adding the black solid, ultrasonically dispersing at 10-60 degrees C in a water bath, adding concentrated sulfuric acid into obtained solution, stirring for 1-5 hours, washing resultant mixture with deionized water, centrifuging and vacuum-drying. The content ratio of graphene oxide and clear orange solution of graphene quantum dot is 20-40 mg:10-30 mL. The content ratio of solid sodium thiosulfate and deionized water is 1-3 g:150-500 mL. The content ratio of polyethylene glycol 4000 and deionized water is 0.1-0.5 g:150-500 mL. The volume ratio of concentrated hydrochloric acid and deionized water is 10-20 mL:150-500 mL. The volume ratio of black solution and deionized water is 1:15-25. The content ratio of sucrose and deionized water is 0.1-1 g:1-5 mL. The content ratio of black solid and deionized water is 0.01-0.1 g:1-5 mL. The volume ratio of concentrated sulfuric acid and deionized water is 3-10 mL:1-5 mL. The graphene oxide is prepared by dispersing flaky graphite and sodium nitrate in concentrated sulfuric acid, slowly adding potassium permanganate for 5-15 minutes, heating obtained mixture at 5-10 degrees C for 1-5 hours, further heating at 20-80 degrees C for 1-24 hours, adding deionized water in an amount of 0.5-3 times of the resultant mixture under an ice-water bath condition, heating at 60-150 degrees C for 1-5 hours, cooling resultant mixture to room temperature, adding deionized water in an amount of 1-4 times of the resultant mixture, stirring for 10-30 minutes, aging for 1-5 hours, filtering, washing, centrifuging, and vacuum-drying obtained precipitate. The mass ratio of flaky graphite and sodium nitrate is 1:1. The content ratio of flaky graphite and concentrated sulfuric acid is 0.5-5 g:30-100 mL. The content ratio of potassium permanganate and concentrated sulfuric acid is 6-12 g:30-100 mL.