▎ 摘　　要

NOVELTY - Pre-oxidized graphite is added to concentrated sulfuric acid, stirred, and potassium permanganate is added and dissolved. The resultant mixture is reacted for 0.5-20 hours, and water is added and continuously stirred. Obtained mixed solution is diluted, and hydrogen peroxide solution is added and stirred. The resultant mixture is left to stand and supernatant liquid is collected and removed. The remaining suspension is treated with hydrochloric acid solution, cleaned, diluted, and dialyzed to obtain highly-dispersible graphene oxide hydrogel. USE - Preparation of highly-dispersible graphene oxide hydrogel used in functional materials, energy storage device and biosensor. ADVANTAGE - The method efficiently provides highly-dispersible graphene oxide hydrogel having excellent film-forming performance and high conductivity. DETAILED DESCRIPTION - A mixed oxidant containing phosphorus pentoxide and manganese(III)oxide, is added to concentrated sulfuric acid at 60-180 degrees C, stirred until completely dissolved, and the temperature is reduced to 40-160 degrees C. Graphite is added to the resultant mixture, reacted for 1-10 hours, washed using water until the filtrate is neutral, and dried to obtain pre-oxidized graphite. In 0-50 degrees C water bath, the pre-oxidized graphite is added to concentrated sulfuric acid, stirred, and potassium permanganate is added and dissolved. At 10-100 degrees C, the resultant mixture is reacted for 0.5-20 hours, and water is added and continuously stirred at 10-100 degrees C for 1-10 hours. The obtained mixed solution is diluted using water, and hydrogen peroxide solution is added and stirred. The resultant mixture is left to stand and the supernatant liquid is collected and removed. The remaining suspension is treated with hydrochloric acid solution, and cleaned several times. The obtained product is then diluted using water, and the supernatant is removed. The suspension is dialyzed until the dialyzate does not contain free state sulfate ion, to obtain highly-dispersible graphene oxide hydrogel.