▎ 摘　　要

NOVELTY - Preparing cobalt nanoparticle and reduced graphene oxide electromagnetic wave absorbing material comprises (i) dissolving precursor and reducing agent in de-ionized water to obtain precursor solution and reducing agent solution, uniformly mixing reducing agent solution and precipitating agent by magnetic stirring to obtain uniformly mixed solution of reducing agent and precipitating agent, (ii) magnetically stirring precursor solution at 30-60 degrees C in constant temperature water bath, titrating uniform mixed solution of reducing agent and precipitating agent with precursor solution at a rate of (1-5) drops/second, centrifuging and drying product to obtain surface oxidized magnetic metal cobalt nano particle, and (iii) ultrasonically dispersing surface oxidized magnetic metal cobalt nano particle and reduced graphene oxide in high frequency ultrasonic machine for 2-6 hours, centrifugally separating the product and placing in the vacuum drying box and drying for 4-6 hours under vacuum. USE - The method is useful for preparing cobalt nanoparticle and reduced graphene oxide electromagnetic wave absorbing material. ADVANTAGE - The material has low density, good dispersibility and frequency range of 2-18 GHz. DETAILED DESCRIPTION - Preparing cobalt nanoparticle and reduced graphene oxide electromagnetic wave absorbing material comprises (i) dissolving precursor and reducing agent in a molar ratio of (1-1.5):(2-4) in the de-ionized water to obtain precursor solution and reducing agent solution, uniformly mixing reducing agent solution and precipitating agent by magnetic stirring to obtain uniformly mixed solution of reducing agent and precipitating agent, (ii) magnetically stirring precursor solution at 30-60 degrees C in constant temperature water bath, titrating uniform mixed solution of reducing agent and precipitating agent with precursor solution at a rate of (1-5) drops/second, centrifuging and drying product to obtain surface oxidized magnetic metal cobalt nano particle, and (iii) ultrasonically dispersing surface oxidized magnetic metal cobalt nano particle and reduced graphene oxide in a mass ratio of (5-15):1 in high frequency ultrasonic machine for 2-6 hours, centrifugally separating the product and placing in the vacuum drying box and drying for 4-6 hours under vacuum.