Method for preparing tetragonal Eu-doped LaOF red nano fluorescent powder

The invention relates to a preparation method of four-phase lanthanum oxyfluoride europium ion doped red nanometer fluorescent powder represented by the general formula La1-xEuxOF, wherein, x is less than or equal to 0.15 and more than or equal to 0.01, and the preparation method has the following steps of: preparing a water solution of Eu(NO3)3, reacting of materials, drying centrifugally, roasting and grinding. Test results prove that the four-phase lanthanum oxyfluoride europium ion doped red nanometer fluorescent powder prepared by the invention is a four-phase crystal structure, and compared with Honest R fluorescent powder and ERT4E-002 fluorescent powder, the wave length range of the red fluorescent emission belt is close to that of the Honest R fluorescent powder and the ERT4E-002fluorescent powder, and the total score strength (the photon number) of the red fluorescent emission belt is respectively more than three times than that of the Honest R fluorescent powder and the ERT4E-002 fluorescent powder