▎ 摘　　要

NOVELTY - Preparing core-shell structure comprises (1) taking graphene and dispersing it in a mixed solution of deionized water and ethanol to obtain solution A, and subjecting the solution A to water ultrasonic treatment and crushing to obtain solution B, (2) taking mixed solution of hydrochloric acid and sodium silicate to obtain solution C, stirring solution B, and adding aqueous ammonia and solution C to solution B during the stirring process to obtain solution D, and (3) centrifuging the solution D, washing using deionized water and ethanol to obtain a centrifugal product, and drying the centrifugal product to obtain a core-shell structure. USE - The core-shell structure is useful for preparing zirconium alloy extruding lubricant (claimed). ADVANTAGE - The method: does not generate other impurities during the reaction process; is simple and easy to operate; and the obtained nano silica particles are uniform in size. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for core-shell structure prepared by the above preparation method, comprising a graphene base layer and silica particles deposited on the base layer, and the silica particles has a particle size of 180-240 nm.