Low temperature ammonothermal synthesis of europium-doped SrAlSiN 3 for a nitride red phosphor

Abstract

Because of its use as a mother crystal of red phosphor in white LEDs, SrAlSiN3 is a very interesting complex nitride. Till date, the only examples of europium-doped SrAlSiN3 synthesis have been in high-pressure nitrogen atmospheres at high temperatures above 2000K at 190MPa with typical solid-state reaction. In comparison, our research is the first to achieve such synthesis at an extremely low temperature of 773K at 100 MPa. In addition, we document the first instance of synthesis using supercritical ammonia fluid with NaNH2 as a reaction medium. Moreover, to our knowledge, this report details the first instance of synthesis of europiumdoped SrAlSiN3 by using dissolution and precipitation reaction. Reaction temperature and time dependencies of ammonothermal reactions for the product are investigated. The obtained product exhibits a red emission by irradiation of blue light of 460 nm. © 2012 The Ceramic Society of Japan. All rights reserved.