▎ 摘　　要

NOVELTY - A graphite oxide is added into water and dispersed ultrasonically for 1-2 hours, to form graphene oxide colloid. A p-phenylenediamine is dissolved in N,N-dimethylformamide, to obtain p-phenylenediamine solution. The graphene oxide colloid and p-phenylenediamine solution are mixed, and the resulting mixture is poured into a three-neck round flask, boiled and stirred. The resulting colloid is filtered and washed using acetone, to obtain wet powder of graphene. The wet powder of graphene is then added into ethanol, to obtain black graphene colloid. USE - Preparation of graphene colloid and graphene poly-p-phenylenediamine composite material. ADVANTAGE - The graphene colloid having excellent dispersibility is prepared. DETAILED DESCRIPTION - A graphite oxide is added into water and dispersed ultrasonically for 1-2 hours, to form graphene oxide colloid having a mass concentration of 0.1-1 mg/ml. A p-phenylenediamine is dissolved in N,N-dimethylformamide, to obtain p-phenylenediamine solution having mass concentration of 9-18 mg/ml. The graphene oxide colloid and p-phenylenediamine solution are mixed in a volume ratio of (1-2):1, and the resulting mixture is poured into a three-neck round flask, boiled at an oil bath temperature of 80-120 degrees C, refluxed and stirred for 12-24 hours, to obtain red graphene colloid. The red graphene colloid is filtered and washed using acetone, to obtain wet powder of graphene. The wet powder of graphene is then added into ethanol for ultrasonic dispersion, to obtain black graphene colloid having mass concentration of 0.05-0.5 mg/ml. Potassium persulfate aqueous solution containing potassium persulfate and water in a mass ratio of 1:(27-45), and concentrated hydrochloric acid are added into the red graphene colloid that is not filtered and washed, and reacted in an ice bath for 6-24 hours. The resulting product is sequentially washed with acetone, 0.1 mol/L hydrochloric acid and water, and dried, to obtain graphene poly-p-phenylenediamine composite material. The mass ratio of water and graphite oxide is (1000-10000):1. The ratio of p-phenylenediamine to N,N-dimethylformamide is (52-104):1. The volume ratio of red graphene colloid, water and concentrated hydrochloric acid is (50-100):(15-30):1.