Synthesis of AlN: Eu2+ green phosphors by a simple direct nitridation method

Eu‐doped aluminum nitride phosphors were successfully prepared using simple direct nitridation of a metallic aluminum and Eu₂O₃ powder mixture in flowing ammonia. AlN formed at reaction temperatures >900°C, and Eu³⁺ transformed into the secondary oxide phase EuAl₂O₄ in the nitridation condition. Phase pure AlN was obtained by post‐heat treatment of the nitridated product at 1600°C for 3 h in a nitrogen atmosphere, with an Eu²⁺ doping concentration < 0.5%. The phosphors exhibited broad green emission centered at 521 nm under 363 nm excitation. The luminescence of the phosphor was significantly influenced by the post‐heat treatment temperature, which affected the dissolution of Eu²⁺, phase purity, crystallinity, and particle size of the AlN host.