▎ 摘　　要

NOVELTY - A composite material comprises 85-95 wt.% graphene oxide and 5-15 wt.% phosphoramide radical integrated by covalent bond, where phosphoramide radicals are distributed on surface of graphene oxide. USE - Composite material. ADVANTAGE - The composite material solves the problem about insufficient adsorption capacity of uranium oxide and difficult water phase separation. The method has simple operation, low production cost and high yield, and is suitable for large-scale industrial production. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of composite material comprising: (A) adding graphite powder into reactor containing concentrated sulfuric acid, stirring for 20-60 minutes, placing reactor in ice water bath, slowly adding potassium permanganate solution, stirring at 33-36 degrees C for 1.5-2.5 hours, adding ultra-purified water, heating to 88-92 degrees C, slowly adding hydrogen peroxide solution, filtering, washing with hydrochloric acid diluted by ultra-purified water, washing, removing soluble impurities, dialyzing, high-speed centrifuging and vacuum-drying at 55-65 degrees C for 1.5-2.5 hours to obtain graphene oxide; (B) taking diethyl chlorophosphate as phosphorus source, 3-aminopropyltrimethoxysilane as coupling agent and triethylamine as catalyst at molar ratio of 1: 0.8-1.2: 0.8-1.2, dissolving in organic solvent under nitrogen protection, adding chlorodiethyl phosphate at 0-5 degrees C while strongly stirring, heating to room temperature, continuously reacting for 6-15 hours, filtering and rotary evaporating filtrate at 52-68 degrees C to obtain phosphoramide light yellow liquid; and (C) dispersing graphene oxide powder in anhydrous ethanol, ultrasonically processing for 20-45 minutes under inert gas protection at room temperature, adding phosphoramide light yellow liquid while strongly stirring, continuously stirring after adding for 2.5-4 hours, heating under reflux for 4-6 hours, filtering by microporous filtering film and drying at 45-55 degrees C to obtain black powder.