▎ 摘　　要

NOVELTY - A nano-absorbing material comprises 210-250 nm sphere or spheroid iron oxide composite silica nanoparticles and flaky graphene. The inner iron oxide is coated with silica nanoparticles. USE - Nano-absorbing material. ADVANTAGE - The nano-absorbing material is flexible and environment-friendly, and has good absorbing effect, greatly improved capacity, wide frequency absorption section. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of nano-absorbing material comprising: (A) dissolving trivalent iron salt, monovalent metal acetate and disodium EDTA or dipotassium EDTA at molar ratio of 0.8-1.2:5-7:0.001 in ethylene glycol, transferring into sealed autoclave, heating to 180-220 degrees C at autogenous pressure for 8-12 hours, naturally cooling to room temperature, washing, and drying to obtain iron oxide nanoparticle clusters; (B) mixing ethanol, deionized water and concentrated aqueous ammonia at ratio of 6-10:0.5-0.5:0.01-0.05, adding 0.04-0.06 wt.% iron oxide nanoparticle clusters, ultrasonically dispersing, dropping tetraethyl orthosilicate, ultrasonically stirring for 1-3 hours, washing, and drying to obtain iron oxide composite silica nanoparticles; and (C) dispersing 0.06-0.07 wt.% pre-oxidized graphite in deionized water, heating, adding hydrazine hydrate, stirring for 2-3 hours to obtain suspension, cooling to room temperature, adding iron oxide composite silica nanoparticles, ultrasonically dispersing, washing, and drying. The concentrated aqueous ammonia has ammonia content of 22-25%.