Magnetic fluorescent nano composite material as well as preparation method and application thereof

The invention discloses a magnetic fluorescent nano composite material and a preparation method and application thereof, and the preparation method comprises the following steps: 1, preparing magnetic Fe3O4 nano particles from ferric chloride and ferrous chloride through a coprecipitation method; 2, preparing La2 (MoO4) 3: Eu < 3 + > fluorescent nano particles from three rare earth ions including lanthanum ions, europium ions and molybdenum ions through a hydrothermal method; and 3, adding the La2 (MoO4) 3: Eu < 3 + > fluorescent nano-particles and the magnetic Fe3O4 nano-particles into ultrapure water or absolute ethyl alcohol according to a proportion by using a blending method, and blending to obtain a magnetic fluorescent nano-composite material. The magnetic fluorescent nano composite material can instantly generate an electric field after a circuit is short-circuited, so that the detection sensitivity is effectively enhanced, the indication time of a display is prolonged, and the fault detection efficie