The Effect of Pretreatment of Raw Powders on the Photoluminescence of Ca-α-SiAlON:Eu²⁺Phosphor

Abstract

The effect of calcination treatment of raw powders prior to high temperature synthesis of Ca-α-SiAlON:Eu 2+ phosphor was investigated. Based on data acquired from thermogravimetric analysis, calcination temperatures were set at 600, 750, and 900 o C. Compared to the photoluminescence (PL) intensity of direct synthesis without calcination, a similar intensity was found for the 600 o C treatment, a 19% increased PL intensity was found for the 750 o C treatment, and a 23% decreased PL intensity was found for the 900 o C treatment. Observation of the particle morphology of the synthesized phosphors revealed that the material transport promoted through the agglomerates formed by the 750 o C treatment led to enhanced PL intensity. On the other hand, the oxidation of the starting AlN particles during the 900 o C treatment resulted in decreased photoluminescence.