▎ 摘　　要

NOVELTY - A spinel-type ferromagnet/graphene nanocomposite comprises iron oxide magnetic nanoparticles with uniform particle size and graphene. USE - Spinel-type ferromagnet/graphene nanocomposite is used for detecting small molecules of hydrogen peroxide and glucose (all claimed). ADVANTAGE - The nanocomposite is prepared economically by simple process. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of spinel-type ferromagnet/graphene nanocomposite. 0.03-0.3 g graphene oxide is added to reaction apparatus containing 20-200 mL diethylene glycol solvent and ultrasonically dispersing for 1-5 hours. Then, 0.12-1.2 g ferromagnetic divalent metal salt is added and stirred at 190-220 degrees C for 0.5-2 hours under inert gas protection. Then, 10-100 mg/mL sodium hydroxide/5-50 mL stock solution is added to the mixture, heated at 190-220 degrees C for 1-5 hours, centrifuged and washed, to obtain spinel-type ferromagnet/graphene nanocomposite. The ferromagnetic divalent metal salt is zinc salt, cobalt salt, nickel salt, manganese salt or copper salt.