▎ 摘　　要

NOVELTY - A graphene oxide-coumarin derivative fluorescent material (I), is new. USE - New graphene oxide-coumarin derivative fluorescent material is used as fluorescent probe for detecting trivalent iron ions, or adsorbent for trivalent iron ions (all claimed) in water treatment application. ADVANTAGE - The graphene oxide-coumarin derivative fluorescent material as fluorescent probe has quick response time, and enables detection of trivalent iron ions with high selectivity. When the fluorescent material is used as fluorescent probe, the detection limit of iron is as low as 5.76 mu mol/L, and anti-interference ability is improved. When the fluorescent material is used as adsorbent, the adsorption capacity of iron is more than 50 mg/g. DETAILED DESCRIPTION - A graphene oxide-coumarin derivative fluorescent material of formula (I), is new. INDEPENDENT CLAIMS are included for the following: (1) preparation of the compound (I), which involves adding (i) graphene oxide to toluene and ultrasonically-dispersing for 1-2 hours to obtain a graphene oxide dispersion, dripping 3-aminopropyltriethoxysilane into the graphene oxide dispersion under stirring conditions, reacting at 30-50 degrees C for 2-3 hours, heating to boiling, reacting for 2-3 hours under reflux condition to obtain a black mixed liquid, cooling to room temperature, filtering, repeatedly washing with toluene, and vacuum-drying to obtain an intermediate product (a), ultrasonically-dispersing (ii) the product (a) in deionized water, adding glyoxal aqueous solution, stirring at room temperature for 2-3 hours, filtering under reduced pressure, washing the filter cake with deionized water and absolute ethanol, and vacuum-drying to obtain an intermediate product (b), and ultrasonically-dispersing (iii) the product (b) in toluene to obtain a dispersion, dripping a toluene solution of coumarin derivative of formula (II) into the dispersion under stirring, increasing the temperature to boiling under nitrogen protection, reacting for 24-36 hours under reflux condition, cooling to room temperature, vacuum-filtering, washing the filter cake with absolute ethanol and dichloromethane, and vacuum-drying; and (2) use of the compound (I) as fluorescent probe for detecting trivalent iron ions, or adsorbent for trivalent iron ions.