SHS of Eu2+-doped β-SiAlON phosphors: Impacts of N2 pressure and Si particle size

Self-propagation high-temperature synthesis (SHS) method was developed as a highly-efficient route for the preparation of Eu-doped β-SiAlON green phosphors. The as-synthesized products with composition Si5.5Al0.5O0.5N7.5:0.035Eu2+ were featured with high phase purity, good uniformity and equiaxed grain morphology. Strong green light emission spectra covering the range of 450-650 nm were obtained under the excitation of UV or blue light. The impacts of the nitrogen pressure in the reaction system and average particle size of Si reactant, which were two of the most vital parameters in the SHS reaction, were systematically investigated. Based on the experimental results, these two factors were confirmed to have striking influences on the phase composition, microstructure and photoluminescence properties of resultant phosphors. In the SHS for β-SiAlON:Eu2+ phosphors, there demonstrated that the selection of N2 pressure of 4 MPa and the utilization of Si reactants with fine particle size would bring about remarkable enhancement in the photoluminescence properties.