▎ 摘　　要

NOVELTY - The preparation method of silicon-coated co-doped cobalt-ferrite microwave absorbent involves adding graphene oxide to deionized water, ultrasonically dispersing, adding urea, and mixing to obtain graphene dispersion liquid, mixing cobalt chloride, ferrous chloride and hydrochloric acid, dripping into graphene dispersion liquid, heating, leaving still, filtering, washing, and drying to obtain graphene/cobalt ferrite, ball milling graphene/cobalt ferrite, yttrium oxide, alumina, and anhydrous ethanol, transferring to ethanol solution, and ultrasonically dispersing. USE - Preparation method of silicon-coated co-doped cobalt-ferrite microwave absorbent. ADVANTAGE - The method enables preparation of silicon-coated co-doped cobalt-ferrite microwave absorbent with excellent flexibility, chemical stability, high thermal conductivity, and improved high-temperature resistance. DETAILED DESCRIPTION - The preparation method of silicon-coated co-doped cobalt-ferrite microwave absorbent involves (1) adding graphene oxide to deionized water, ultrasonically dispersing, adding urea, and uniformly mixing to obtain graphene dispersion liquid, (2) uniformly mixing cobalt chloride, ferrous chloride and hydrochloric acid, dripping into graphene dispersion liquid under nitrogen atmosphere at a rate of 1-2 mL/minute, heating at 90-100 degrees C for 2-3 hours, leaving still for 10-15 hours, filtering, washing, and drying to obtain graphene/cobalt ferrite, (3) taking the graphene/cobalt ferrite, yttrium oxide, alumina, and anhydrous ethanol, placing in a ball mill, ball milling for 20-24 hours, transferring to ethanol solution, and ultrasonically dispersing for 20-30 minutes to obtain co-doped cobalt ferrite dispersion liquid, (4) dripping tetraethyl orthosilicate to the co-doped cobalt ferrite dispersion liquid, uniformly mixing, dripping aqueous ammonia, stirring for 8-10 hours, filtering, washing, and drying.