GREEN PHOSPHOR BASED ON MAGNESIUM THIOGALLATE AND PREPARATION METHOD THEREOF

摘要

Provided are a novel magnesium thiogallate-based green phosphor which has a wide excitation wavelength of 300-510 nm and is useful for an LED, its preparation method, and a display material using the phosphor. The magnesium thiogallate-based green phosphor is represented by Mg_(x-a) A_z Ga_y S_(x+1.5y): Eu_a, wherein A is Ca, Sr or their mixture; 0.4<=x<=4; 2<=y <=12; 0.001<=a<=0.3; and 0<=z<1. The method comprises the steps of weighing magnesium sulfide, gallium sulfide and an activator sulfide and mixing them; and heat treating the obtained mixture at a temperature of 700-1,200 deg.C under the condition of a mixture gas comprising nitrogen and hydrogen. Preferably the ratio of nitrogen and hydrogen is 60-95 : 5-40 by volume.