BLUE FLUORESCENT POWDER FOR THREE PRIMARY COLOR WARM WHITE LIGHT LED AND PREPARATION METHOD THEREFOR

摘要

Disclosed are a blue fluorescent powder three primary color warm white light LED and a preparation method therefor. In the method, strontium carbonate (SrCO₃), anhydrous ammonium chloride (NH₄Cl), boric acid (H₃BO₃), europium sesquioxide (Eu₂O₃) and ammonium dihydrogen phosphate (NH₄H₂PO₄) are used as raw materials; and same are subjected to solid state sintering in a reducing atmosphere to obtain a blue fluorescent powder of formula Sr_(2-x)Eu_x(BO₃)_y(PO₄)_(1-y)Cl, wherein 0.001 ≤ x ≤ 0.1, and 0.001 ≤ y ≤ 0.5. Same is mixed with CaAlSiN₃： an Eu²⁺ red fluorescent powder and (SrBa)₂SiO₄ : an Eu²⁺ green fluorescent powder in a certain ratio to achieve near-ultraviolet excited warm white light emission with a high color rendering index and a high light efficiency, wherein same has very bright application prospects.