Graphene microsphere

[0020] A graphene microsphere comprises the steps of:

[0021] 1) Pretreatment of graphite:

[0022] Graphite was placed in a mixed solution composed of concentrated sulfuric acid and potassium permanganate, and was treated with ultrasonic stirring at 20°C for 5 hours. The obtained product was washed, filtered, and dried, and then placed in a muffle furnace. Treat at high temperature for 0.1 h to obtain expanded graphite product for later use; the mass (g) of graphite in the step: the volume (L) of concentrated sulfuric acid: the mass (g) of potassium permanganate=1:0.05:0.1.

[0023] 2) Preparation of graphene microspheres:

[0024] Dissolve the expanded graphite product obtained in step 1) in deionized water, add 5wt% surfactant, and after ultrasonic stirring for 0.1h, gradually add an appropriate amount of titanium source in the solution, the mass ratio of the titanium source to the expanded graphite precursor is 20 : 1; After ultrasonic stirring for 4 hours, add ammonia wat

[0027] A graphene microsphere comprises the steps of:

[0028] 1) Pretreatment of graphite:

[0029] Graphite was placed in a mixed solution consisting of concentrated sulfuric acid and potassium permanganate, and treated with ultrasonic stirring at 60°C for 0.5h. The obtained product was washed, filtered, and dried, then placed in a muffle furnace, and heated in a nitrogen atmosphere. Treat at 600°C for 6 hours to obtain expanded graphite product for later use; the mass (g) of graphite in the step: the volume (L) of concentrated sulfuric acid: the mass (g) of potassium permanganate=1:0.1:0.1.

[0030] 2) Preparation of graphene microspheres:

[0031] Dissolve the expanded graphite product obtained in step 1) in deionized water, add 0.1wt% surfactant, and after ultrasonic stirring for 2 hours, gradually add an appropriate amount of titanium source in the solution, the mass ratio of the titanium source to the expanded graphite precursor is 0.1 : 1; add ammonia water after ultras

[0034] A kind of graphene microsphere, comprises the steps:

[0035] 1) Pretreatment of graphite:

[0036] Graphite was placed in a mixed solution consisting of concentrated sulfuric acid and potassium permanganate, and treated with ultrasonic stirring at 40°C for 3.5h. The obtained product was washed, filtered, and dried, then placed in a muffle furnace, and heated in a nitrogen atmosphere. Treat at 800°C for 3 hours to obtain expanded graphite product for later use; the mass (g) of graphite in the step: the volume (L) of concentrated sulfuric acid: the mass (g) of potassium permanganate=1:0.07:0.3.

[0037] 2) Preparation of graphene microspheres:

[0038] Dissolve the expanded graphite obtained in step 1) in deionized water, add 3wt% surfactant, and after ultrasonic stirring for 1 h, gradually add an appropriate amount of titanium source in the solution, the mass ratio of the titanium source to the expanded graphite precursor is 10: 1. Add ammonia water after ultrasonic stir