Enhanced quantum efficiency with magnesium doping in europium-containing silicon oxynitride phosphor

Abstract Two types of europium (Eu)-containing silicon oxynitride phosphors were prepared by the polymer-derived method via polycarbosilane and Eu acetylacetonate with/without magnesium (Mg) acetylacetonate. The influences of Mg doping on the phase structure, surface morphology, microstructure and photoluminescence property of the Eu-containing silicon oxynitride phosphor were investigated. It was found that both the phosphors had almost single crystalized particles with a β-Si 3 N 4 like major phase and a strong emission band ranging 430–440 nm. Doping a small amount of Mg ions into the Eu-containing silicon oxynitride phosphor not only enlarged the crystalline and particle sizes, but also significantly enhanced the quantum efficiency from 34.53% to 93.81%. By comparing with the pure silicon oxynitride powder, possible mechanisms for the major emission band in the region of 430–440 nm and the shoulder emission band at around 550 nm are discussed.