▎ 摘　　要

NOVELTY - Preparation of graphene-coated dysprosium dioxide involves dissolving dysprosium acetate in a mixed solvent of ethanol and propionic acid, placing in pyrolysis reaction furnace, reacting at 120 degrees C, heating to 500 degrees C to obtain dysprosium oxide nanoparticles, mixing dysprosium oxide nanoparticles and dysprosium oxide nano-column in mass ratio of 1:(1-3), adding graphene solution, filtering, heating the residue in inert gas temperature at 400-800 degrees C for 0.5-5 hours to obtain graphene-coated dysprosium dioxide. USE - Preparation of graphene-coated dysprosium dioxide for magnesium diboride superconductor material (claimed). ADVANTAGE - The graphene-coated dysprosium dioxide having high specific surface area is produced by simple method without agglomeration of particles. The superconductor material having high critical current density is formed. DETAILED DESCRIPTION - Preparation of graphene-coated dysprosium dioxide involves dissolving dysprosium acetate in a mixed solvent of ethanol and propionic acid to obtain a dysprosium acetate solution, placing solution in a pyrolysis reaction furnace, reacting at 120 degrees C, heating to 500 degrees C in a humid oxygen atmosphere at rate of 0.1-10 degrees C/minute to obtain dysprosium oxide nanoparticles, dissolving dysprosium nitrate in t-butylamine aqueous solution or aqueous solution of amino acid, hydrothermally reacting to produce dysprosium oxide nano-column, adding graphene oxide to mixed solvent of deionized water and ethanol to obtain a graphene solution, mixing dysprosium oxide nanoparticles and dysprosium oxide nano-column in mass ratio of 1:(1-3), adding graphene solution, filtering, heating the residue in inert gas temperature at 400-800 degrees C for 0.5-5 hours to obtain graphene-coated dysprosium dioxide. The volume ratio of ethanol to propionic acid in the mixed solvent is 1:1. The volume ratio of t-butylamine to water is 1:(4-10). The volume ratio of aminoacetic acid to water is 1:(4-10). The volume ratio of deionized water to ethanol in the mixed solvent is 1:(50-100). The concentration of the graphene oxide in the graphene solution is 0.5-10 mg/mL.