Method for synthesizing ferroferric oxide nanoparticles by using osmanthus fragrans extract

The invention discloses a method for synthesizing ferroferric oxide nanoparticles by using an osmanthus fragrans extract. The preparation method comprises the following specific steps: adding deionized water and an osmanthus fragrans extract in a certain volume ratio into a three-neck flask at room temperature, carrying out ultrasonic dispersion and mixing for a period of time, and heating after uniformly mixing; raising the temperature to a certain temperature, adding an alkali source, preparing an iron source into a solution, feeding through a trace feeding device, and adding into the three-neck flask for reaction; reacting for a period of time, after the reaction is completed, pouring out a product for magnetic separation, alternately cleaning the product obtained by magnetic separation with deionized water and absolute ethyl alcohol for multiple times, then carrying out suction filtration, and calcining the product obtained by suction filtration in a muffle furnace at a certain temperature for a period of