▎ 摘　　要

NOVELTY - Preparing ferric oxide/graphene composite material comprises e.g. (i) ultrasonic dispersing graphite oxide in water to obtain graphene oxide solution, adding sulfuric acid, ultrasonic dispersing to obtain mixed liquid, adding mixed liquid into reactor, heating, then washing to obtain three dimensional columnar reduced graphene oxide, (ii) adding precipitant to aqueous iron salt solution to obtain soaking solution, and soaking three-dimensional columnar reduced graphene oxide, and transferring into hydrothermal reactor, reacting, washing and drying to obtain precursor, roasting, and cooling. USE - The ferric oxide/graphene composite material is useful in production of lithium ion battery and lithium-ion battery cathode material (all claimed). ADVANTAGE - The method is useful in large-scale industrial production, and has low production cost. DETAILED DESCRIPTION - Preparing ferric oxide/graphene composite material comprises (i) ultrasonic dispersing graphite oxide in water to obtain graphene oxide solution, adding sulfuric acid, ultrasonic dispersing to obtain mixed liquid, adding mixed liquid into reactor, heating to 160-260 degrees C for 18-30 hours, preferably at 190-220 degrees C for 20-24 hours then washing to obtain three dimensional columnar reduced graphene oxide, (ii) adding precipitant to aqueous iron salt solution to obtain soaking solution, and soaking three-dimensional columnar reduced graphene oxide at 3-60 degrees C for more than 1 day, preferably 10-30 degrees C for 1-3 days, and transferring into hydrothermal reactor, reacting at 160-260 degrees C for 18-48 hours, preferably 180-220 degrees C for 20-28 hours, washing and drying to obtain precursor, and (iii) roasting precursor at 250-550 degrees C for 0.5-6 hours, preferably at 300-450 degrees C for 1-3 hours, and cooling to room temperature naturally to obtain final product.