Effect of starting composition and post-anneal on the structure and luminescence properties of Eu-doped Ca-α-SiAlON phosphors prepared by combustion synthesis

Abstract

Eu-doped Ca-α-SiAlON yellow phosphors, with the compositions Ca0.72Eu0.08Si9.56Al2.44O0.84N15.16, were prepared by a highly efficient combustion synthesis method. By optimizing the starting compositions of reactants and choosing appropriate post-annealing conditions, phase-pure, uniform and fine Ca-α-sialon:Eu2+ phosphors possessing the particle size ranging ∼3–5 μm, and good luminescence properties with an intense emission band that peaks at 592 nm under n-UV or blue light excitation were obtained. The results indicated that combustion synthesis method was an energy efficient, time saving and low cost way to prepare Ca-α-SiAlON phosphors by controlling the mass ratio of comburents. A combination with post-annealing treatment was desired for further increase of the properties of Ca-α-SiAlON phosphors.