METHOD OF SYNTHESIZING COMPOSITE PHOSPHOR BY PHASE TRANSITION

摘要

A method of synthesizing a composite phosphor by phase transition, characterized by controlling the sintering temperature and duration, changing M2−ySi5N8:Ry phase to M1−xSi6N8 : Rx phase, thereby forming a two-phase composite phosphor, wherein proportions of the two phases of the composite phosphor are variable. As indicated by its varying CIE color coordinates, Sr1.98Si5N8:Eu2+0.02 changes from red to pink, and then to blue. The CIE color coordinates are collinear. If there is no color deviation at the two ends of the straight line, the coordinates of any color resulting from a mixture of two colors will lie on the straight line. The aforesaid synthesis method dispenses with the hassles of sintering two colored phosphors separately, thus attaining uniformity of resultant light color and cutting the costs of phosphor synthesis.

主权项

1. A method of synthesizing a composite phosphor by phase transition, the method comprising the steps of:
(a) mixing M3N2, Si3N4, and RNz for use as a synthesis raw material, where M denotes an alkaline earth group element, R denotes a rare earth metal, and z≦1; (b) sintering the synthesis raw material by a high-temperature sintering process, wherein the composite phosphor including M1−xSi6N8:Rx phase phosphor and M2−ySi5N8:Ry phase phosphor is formed by controlling a sintering temperature and a sintering duration of the high-temperature sintering process, where 0≦x<1 and 0≦y<2.